Engine question

[Buffy]

Well I've spent the morning tearing into my engine to see if I can see what is going on with it. I did a compression test and here is what I found:

90 100

120 100

110 100

front

I took the timing cover off the passenger side and everything seemed ok. I took the valve cover off and still everything looked good. Had the wife crank it while the cover was off too see if I gould see anything going on. Got a good oil bath but other than that nothing out of the ordinary. The sound seems like it is coming from under the cylinder head now. Just not sure what my next move should be. What should the compression be on the cylinders?
I am perplexed because the tapping will stop sometimes and then go back to tapping.

Any suggestions???

[Mile High VX]

Here are the inital results from another member that had a bad valve. He's in the UK so not sure if the measurements are comparable, but it's the only one I remember seeing recently.

1 = 190
2 = 170
3 = 180
4 = 0
5 = 170
6 = 165


Guess which cylinder had the bad valve...:bwgy::smilewink:bgwo::bgwb:

The workshop manual list the desired compression at 14.0 Kg/cm2. So to convert that to psi you simply multiply by 14.223 and get 199 psi.

Looks like you may have a gauge issue, or you're gonna need some rings.

Hope this helps...

[Buffy]

I did the compression test on a cold engine and the manual says to have the engine at normal operating temps before testing. I guess I need to warm up the engine and try it again. I just can't figure out the knock.

[SilverBullet75]

http://www.vehicross.info/forums/showthread.php?t=13176&highlight=timing+belt+tensioner

[Buffy]

I may go ahead and do that, heck I am into it this far. I did download the manual and follow the compression testing procedure. The numbers came back much better:
205 210

200 200

195 205
front

[Mile High VX]

I may go ahead and do that, heck I am into it this far. I did download the manual and follow the compression testing procedure. The numbers came back much better:
205 210

200 200

195 205
front

That's what I'm talkin' 'bout!

:clap::clap:

[Buffy]

The wife made and interesting observation. While we were doing the compression that the engine didn't knock when we were turning it over. I'll keep digging into it tomorrow and see if I can make some more progress.

[Buffy]

One thing I didn't mention from uuesterday was when I first took the timing cover off and checked the timing belt, it had a lot of play in it but after turning the motor over a few times the belt is now tight. Now I have all the covers off and here are where my timing marks are:

Left Bank (drivers side)

http://www.supermotors.net/getfile/805061/fullsize/left-bank-(driver).jpg

Right Bank (passenger side)

http://www.supermotors.net/getfile/805063/fullsize/right-bank-(passenger).jpg

Crank Pulley

http://www.supermotors.net/getfile/805060/fullsize/crank-(oil-mark).jpg

The belt has some play in it now. I believe I have my marks in place to start removing the timing belt. Would like to hear from someone before I take the next step.

Thanks!

[Ldub]

Would like to hear from someone before I take the next step.

Thanks!

Hello...:luck:
































I think I'm soooooo funny...:laughing:

This is about the best help anyone can give you...

http://www.vehicross.info/misc/pdf_files/BartsTimingBeltReplacement.pdf

This is also handy...

http://www.vehicross.info/misc/vx_manuals/IV00_01.pdf

[Ldub]

One thing I didn't mention from uuesterday was when I first took the timing cover off and checked the timing belt, it had a lot of play in it but after turning the motor over a few times the belt is now tight. Now I have all the covers off and here are where my timing marks are

The marks look like they all line up properly.

If the belt was loose before, & then somehow got tighter...:_thinking

In my mind that would indicate a problem with the tensioner.

But I haven't done mine yet, so whaddoIknow...:_confused

[MSHardeman]

What Dub said....

I used Bart's (nfpgasmask) timing belt how-to to replace my timing belt about a month ago and the instructions are spot on. Bart doesn't miss a step and the instructions are well written (the pictures help out a lot too).

Looks like your timing marks are all in the right place, but I'm curious as to why the belt would get tighter too.

Good luck.

[Buffy]

I've been following Barts writeup as well and it has helped a lot. Thus far all the parts that I've removed all look in decent shape. Based on the wear on the belt I'm thinking this is the original belt. I will replace everything and hope it stops the knock.

[SilverBullet75]

You are giving me deja vu with the symptoms, etc...
I'm gonna give it a 95%-sure rating...
:smilewink
Of course, you'll have to make sure the marks are correct, etc, but...
Just my opinion...

[psychos2]

If the belt is loose the tensioner is bad. it is really hard to push the tensioner in ,you need a vice to do it. Replace the tensioner. shawn

[Buffy]

My plan is to order the same parts Bart did in his writeup. While waiting on parts I will be soing some serious cleaning in the engine bay and rust removal. I noticed the beginnings of rust under where the radiator sits. That should keep me busy for a week or so!

[MSHardeman]

I have a feeling that whether everyone knows it, or not, most of us have rust under where the radiator sits. I don't really have any rust on my VX anywhere, but when I was doing my timing belt swap I noticed rust right where you're talking about. I also noticed that the back side of my front skid plate (right under the radiator mount) was also rusty. Must be something about how the water drains and pools right in that area.

[SlowPro48]

Dude you like to learn things the hard way don't you? We said in the other thread it's not the valves, check the timing belt tensioner but NO you hadda go and root around under the valve covers. :bgwb: Ha! Ya didn't crack that left side open though didya? Man that corner bolt above #6 looks like a PITA. :madb:

OK since you're now EXPERIENCED in the valve actuating area, I've got a couple questions for you - were any of your clearances out of spec? Also is the valve cover gasket the re-usable type that fits in a groove in the cover or is it the fiber type that sticks to the head and you have to scrape it off? I'm trying to figure out if it's worth taking the time to check valve clearance now that I'm past 100K or just let it ride...


I believe I have my marks in place to start removing the timing belt. Would like to hear from someone before I take the next step.

Cams look good but your crankshaft is off by 180 degrees. The #2 TDC notch at the back of the pulley should be lined up with the mark on the oil pump. The timing mark on the front of the pulley (shown in your pic marked with green paint) is what you align the dotted line on the new belt with. It is 180 degrees from the notch. If you look carefully you will probably see a green dot behind the pulley, opposite the mark cast in the oil pump. When the crank is oriented properly for timing belt installation, the green dot on the pulley, the dotted line on the belt and the green dot on the pump all line up - so keep all your dots in a row! That green dot painted on the pump is pretty fat though - i.e., just for information not for lining things up - so for the sake of accuracy, position the crank according to the cast mark on the pump and the #2 TDC notch on the pulley. One thing to note - you don't need to have the marks on the belt lined up for removal - they are there for proper belt installation only. You just need to have all the hard parts in their proper places - and KEEP them there during the installation. The belt is marked to make sure you've got the proper number of teeth between each component so all are properly synchronized but due to the ratio of crank to cams and the unequal number of teeth between marks for crank, left cams and right cams it takes quite a few turns before all six markers line up again. You'll see once you install a belt and crank the engine around by hand a few times to check for interference. I was going to see how many turns it took just for kix but my wimpy arm gave out after about 10 turns. You left the spark plugs out after your last compression test right? Sure makes turning the engine easier!

[Buffy]

I tend to learn things the hardway sometimes, besides I like to see what makes things tick.... quite literally in this case. I haven't checked any of the clearances yet.... probably because I didn't think to do it. :o The valve cover gaskets are the re-usable type. I can attest that the # 6 cover bolt is a serious pain the the :mado:. That was the only bolt that was tough though. Also, taking the power packs out really makes removing the valve cover easy. :p After that brain fad I decided it was time for a sammich and a Gatoraide!.

I was following Bart's wright up on the timing belt install and his instructions were 180 degrees from your instructions. Bart's instructions have you to align the green mark on the pully with the mark on the oil pump and the dotted line with the notch on the back of the pulley.

[nfpgasmask]

Yeah, its been a while, but as far as I remember it, the GREEN LINES on the pulleys line up with the NOTCHES on the housing. You DO NOT need to line up the marks on the OLD belt to check for correct timing. The marks on the belt are ONLY for reinstallation of a new belt.

Now, from looking at your photos, I would almost say you might be a tooth off here:

http://www.supermotors.net/getfile/805061/fullsize/left-bank-(driver).jpg

But everything else looks correct from what I can see. For every full manual turn of the crankshaft pulley, your tick marks should line up the same every time. And again, I am talking about the marks on the pulleys with the marks on the housing. Only during new belt installation do you pay attention to the marks on the belt. This is to ensure you install the belt correctly and are not a single tooth off.

I think my instructions are a little easier to navigate here:
http://www.nofuture.com/myvx/how-tos/tb/tbelt.htm

Keep us posted. :thumbup:

Bart

[nfpgasmask]

Here's the diagram from the manual, it shows the dotted line on the left and the tick mark on the right lined up with the housing.

http://www.nofuture.com/myvx/how-tos/tb/025.jpg

So like I said, it looks like you have things correct. I would certainly take this opportunity to change out the tensioner.

Bart

[Marlin]

I have what I thought was the valve ticking also, but I am going to go ahead and replace the tensioner, looks like that can be done without removing the timing belt? I just had the belt put in about 6K miles ago(last Jan).

[SilverBullet75]

Yes, that is correct. You just need to use something to keep the belt in place when you remove the tensioner. A helper with a prybar pushing/lifting the roller arm helps.

[SlowPro48]

Ahh, so you DID tackle the left side valve cover! You're the man! Thanks for the info on the gasket. If you check your valve lash how about letting us know if you've got any out of spec or close to it. It's something that doesn't get checked very often so it would be good info to see what the results are for an example like yours with close to 100K on the clock. I haven't checked mine for three reasons - #6 bolt, not sure about gasket ( i hate scraping/cleaning!) and the #1 reason - what to do if I find one out of spec? I've got shims but that bucket depressor tool is big bucks for something that gets used once every ten years! You blew my first two excuses out of the water so maybe it's time to fab up a tool and dive on in...

RE: timing belt instructions - yes, I was faced with that dilemma because I went by Bart's excellently documented timing belt replacement (except for the radiator removal - I just yanked the hoses and upper fan shroud out of the way and left the rad in - there was still plenty of room to work) but when I got to the part about installing the belt on the crankshaft pulley I saw his instructions didn't jibe with the shop manual, the bulletin or the videos put out by Isuzu - so I went with what the manufacturer said. Bart sorry man but you got outvoted! :p Take a close look at the figure you just posted. #8 in the illustration shows a closeup of the dots on the belt lined up with tick mark on the FRONT of the pulley - #7 shows the notch at the BACK of the pulley lined up with the mark that is cast in the oil pump housing. Note that the notch lines up with the keyway on the crankshaft. Note that in the illustration, the keyway is 180 degrees from the dotted line on the belt. Now check out the pic of the crank pulley in your instructions and note where the keyway is in relation to the dotted line on the belt.

It obviously works with the crank turned 180 degrees from how Isuzu said to line it up though - so that must be one of the "valid" combinations - i.e., if you line it up the way Isuzu says to do it, then spin it a bunch of times, it eventually ends up with solid belt lines, cam sprocket lines, and head lines all matched up but dotted belt line 180 degrees from point of beginning on the crank sprocket. That's my guess anyway. It could be figured out mathematically but that would require someone with a lot more smarts than me! :yesb:

[nfpgasmask]

Take a close look at the figure you just posted. #8 in the illustration shows a closeup of the dots on the belt lined up with tick mark on the FRONT of the pulley - #7 shows the notch at the BACK of the pulley lined up with the mark that is cast in the oil pump housing. Note that the notch lines up with the keyway on the crankshaft. Note that in the illustration, the keyway is 180 degrees from the dotted line on the belt. Now check out the pic of the crank pulley in your instructions and note where the keyway is in relation to the dotted line on the belt.

:_huh: Either we are saying the same thing but in different ways, or I am totally confused with what you are saying!! :laughing:

Here is my pic:
http://www.nofuture.com/myvx/how-tos/tb/029.jpg
You can clearly see the tick mark on the crankshaft pulley pointing to the right if you were facing the motor. You can also clearly see the line on the housing.

#8 is described as "Alignment Mark On Timing Belt". That's all it is pointing to. With the timing belt OFF, you can see there are 3 marks. There is the line on the oil pump housing on the right side. There is a NOTCH on the pulley itself on the back, you can see it here:
http://www.nofuture.com/myvx/how-tos/tb/042.jpg

Then, there is the green tick mark on the FRONT of the pulley.

The dotted line on the NEW belt gets lined up on the LEFT side with the NOTCH ON THE BACK of the pulley (as in the photo above). At the same time, the green tick mark on the FRONT of the pulley gets lined up with the line on the oil pump housing.

So are you telling me that is backwards? If so then my VX has been backwards from the factory! :laughing:

Either way, whatever I did worked fine. I've put over 20k on my VX since I did the timing belt. What does concern me though is if my instructions have an error or if they are confusing somehow. So kids, please help me work that out! Mark, you used my instructions with success, correct? Did you find any errors you needed to work around? The last thing I want to do is cause confusion and/or problems.

Thanks,

Bart

[MSHardeman]

Bart, the only two issues I came across using your instructions.

One was the location of the short bolts on the water pump. I know in your instructions you said to pay attention to where the short bolts where, but since you had a pretty picture already there, I didn't pay attention. There where one or two more short bolts than you had labeled in your picture so it took me a while to figure out where the other went. No biggie.

The second thing that you forgot to mention was to put the plug back into the bottom of the radiator. Since I tend to be mechanically inept I followed your instructions by the letter and once I got everything back together I started putting fluid back in the radiator and heard it pouring all over the floor. I paniced for a second (thinking something was terribly wrong) until my brain locked in and remember that I hadn't put the plug back in the radiator. Again, no biggie, just me being blond.

As for the instructions on lining up all the marks on the pulleys, belt, and engine; everything worked out great. Followed your instructions to the letter and it all worked out. Went through many miles, and Moab, since the timing belt swap and haven't had an issue yet.

I think everyone is saying the same thing...in a different way.

[psychos2]

I have said it in a previous post. Make marks on the old belt and pulleys before removing, and count the teeth between the marks,make the same marks on the new belt. Install so that your marks line up and you will have no problems. The factory marks on the belt I purchased were wrong so if I had used them my cam timing would have been wrong. shawn

[nfpgasmask]

One was the location of the short bolts on the water pump. I know in your instructions you said to pay attention to where the short bolts where, but since you had a pretty picture already there, I didn't pay attention. There where one or two more short bolts than you had labeled in your picture so it took me a while to figure out where the other went. No biggie.

Hmm, yeah, being that I wrote my how-to after the fact, I might have missed one or two. I'll try to go back and look at my pic/text about the bolts and see if I can't figure it out and make it more clear.


The second thing that you forgot to mention was to put the plug back into the bottom of the radiator. Since I tend to be mechanically inept I followed your instructions by the letter and once I got everything back together I started putting fluid back in the radiator and heard it pouring all over the floor. I paniced for a second (thinking something was terribly wrong) until my brain locked in and remember that I hadn't put the plug back in the radiator. Again, no biggie, just me being blond.

OK now THAT is funny. :laughing: Sorry about that, I will add that back into my instructions. :laughing:


I think everyone is saying the same thing...in a different way.

I hope so! Otherwise my instructions might be giving some folks a huge headache!! :D

Bart

[SlowPro48]

So are you telling me that is backwards? If so then my VX has been backwards from the factory! :laughing:

Not really "backwards"..... just.... different! :bgwb:

Backwards would be if you lined the cam sprockets up with their marks, took the old belt off, then turned the crank 180 degrees and installed the new belt. Now that would be a biggie. You lined everything up, took the old belt off, didn't move anything, and put the new belt back on - so cams and crank stayed in synch. None of the three components were moved and the number of teeth between each one stayed the same. Nothing changed as far as the engine knew. Nothing backwards about that. There obviously is a point in the rotation sequence where the cam sprockets and marks line up but the dotted line on the belt lines up 180 degrees from where it was first installed on the crank sprocket - otherwise what you did would not work. Or hey - maybe you're just benefiting from the VX's wasted spark ignition! Your #2 is now your #5! Nah just kidding!

Bottom line is you installed the belt with the crank turned 180 degrees from where Isuzu said it should be - but it still works - so no biggie! I doubt they did it one way at the factory and told us to do it another though. Just be glad it lines up both ways! :yesb:

BTW, sorry for the confusion. I will attempt to clarify using proper Isuzu terminology. :bgwb: The "Alignment Mark on Timing Belt" (aka "dotted line") is suppsed to be lined up with the "Alignment Mark on Crankshaft Timing Pulley" (aka "green tick mark") which is 180 degrees from the "Groove on Crankshaft Pulley" (aka "notch") which is supposed to be lined up with the "Alignment Mark on Oil Pump" (aka "line on oil pump housing"). See image below.


http://www.vehicross.info/gallery/data/500/tbelt_marks.JPG

[Buffy]

I will be ordering new everything later this week and am keeping my fingers crossed it fixes it. Until then I am cleaning the engine bay as best I can. It is already looking MUCH better than before. Going to order some rust encapsulator and chassis paint from Eastwood today and work on stopping the rust before it goes any further. Anyone have a favorite rust killer that they've had good results with??

[Ldub]

Anyone have a favorite rust killer that they've had good results with??

http://forum.planetisuzoo.com/viewtopic.php?t=7227&highlight=rust+bullet

There is more if you search "rust".

[nfpgasmask]

The "Alignment Mark on Timing Belt" (aka "dotted line") is suppsed to be lined up with the "Alignment Mark on Crankshaft Timing Pulley" (aka "green tick mark") which is 180 degrees from the "Groove on Crankshaft Pulley" (aka "notch") which is supposed to be lined up with the "Alignment Mark on Oil Pump" (aka "line on oil pump housing"). See image below.

http://www.vehicross.info/gallery/data/500/tbelt_marks.JPG

OK yeah, this diagram shows it better. So how is it then that mine didn't line up that way? I mean, like you said, I removed the belt and put the new one on and I DID NOT turn anything while the old belt was off, so obviously I had no issues, same for Mark I am guessing. Is it possible that these reference marks are there for when you have the timing belt break and you need to get everything back right again? It's just weird to me, because when I turned the motor over by hand with the old belt on, the notch in the pulley always ended up at the 9:00 o'clock position when the LH Camshaft pulley and RH camshaft pulley were in the right spots....:wtfy:

Bart

[MSHardeman]

YEP, Bart, I followed your instructions and everything seems to be working for me too. When the left and right hand cam pulleys where lined up on their marks, the mark on the crank pulley was lined up with the mark on the engine and the notch on the pulley was 180 degrees away from that. Installed the new belt (Isuzu) with the marks on the cam pulleys lined up and the dotted line lined up with the notch on the crank (again 180 degrees from both the mark on the crank pulley and the engine case). I do remember reading something, somewhere on how to get your timing back if your belt broke and completely threw everything off, just can't remember where.

BTW, Bart, could you make some space in your PM box? Can't respond b/c it's full.

[nfpgasmask]

YEP, Bart, I followed your instructions and everything seems to be working for me too. When the left and right hand cam pulleys where lined up on their marks, the mark on the crank pulley was lined up with the mark on the engine and the notch on the pulley was 180 degrees away from that. Installed the new belt (Isuzu) with the marks on the cam pulleys lined up and the dotted line lined up with the notch on the crank (again 180 degrees from both the mark on the crank pulley and the engine case). I do remember reading something, somewhere on how to get your timing back if your belt broke and completely threw everything off, just can't remember where.

Yeah, I know the Isuzu video shows both the timing belt change if the timing is good and the timing belt change if the timing is broken. But yeah, what you described above is exactly how mine was.


BTW, Bart, could you make some space in your PM box? Can't respond b/c it's full.

Done, thanks.

Bart

[Scott Larson]

So confused! I followed Bart's how-to after perusing all the other how-to's on the subject and had no issues/questions whatsoever...great tech write-up Bart!! Still curious about the "Chocolate Monkey" though...

[nfpgasmask]

Still curious about the "Chocolate Monkey" though...

That was inserted by Tom, you'll have to ask him...

Bart

[SlowPro48]

Yes, Scott, it IS a great write-up. In fact I think it's the best I've ever seen as far as attention to detail, how methodical it is and of course all the pics are very helpful - so Bart I hope you don't think I'm picking on your How-To. Burlington Buffy asked if he had his shyte lined up right and I just pointed out it's 180 degrees from what Isuzu says to do. I've already presented my hypothesis as to why it works when lined up with #2 and #5 at BDC instead of at TDC like the manual says they should be - but I'll leave it up to someone else to come up with a definitive answer - or for all I care it can remain a mystery like that thing hovering in the back yard when I was a kid or the strange, strange pond with sides like glass in the woods near here....

That is all.

[nfpgasmask]

SlowPro, not at all. For me, it's just that I want my how-to to be correct, accurate, concise and NOT confusing. Most of all, I don't want to point anyone in the wrong direction and have them eff up something with their VX.

The "chocolate monkey" thing might just do that (:rotate:), so I always point people to the original how-to here:

http://www.nofuture.com/myvx/how-tos/tb/tbelt.htm

The above link is from my website, and if I make any revisions, you will see them there, but not in the PDF that Tom made of my original how-to back when I originally posted it. In fact I do think there are some minor changes on my site that ARE NOT in the PDF currently. Plus, I think my website is a better format and easier to follow. While the PDF is easier for people to find, I encourage everyone to visit the instructions on my site over the PDF.

I think the most confusing part for me now, is I sit here wondering what would have happened if I was to:

A) remove the tensioner
B) remove the original belt
C) turn the crankshaft pulley to move the notch to the right side, aligned with the mark on the oil pump housing, with the green line on the top of the pulley on the other side
D) put new belt on

Would my timing be OK or off? It's just so weird in my head because with the original belt still on, when I turned the crank shaft pulley to align the LH and RH camshaft marks, the notch was ALWAYS at the 9:00 o'clock position and the green line always lined up with mark on the oil pump, so I figured I had it right.

Personally, I think the Isuzu shop manual sucks. It's vague, the illustrations are terrible (they look like 10th generation photo-copies), and it assumes you have been a mechanic for 25 years (can't fault them there though).

Are there any other folks besides Mark who have done the timing belt change themselves? I'd be curious to know how things look for different people. SlowPro, you did the swap yourself and aligned the notch in the back of the crankshaft pulley with the mark on the oil pump. So, when you did it, did your marks on the LH and RH line up as well? So weird.

Bart

PS - I started working on a new how-to for the tranny fluid change but my camera's flash crapped out in the middle of doing it. :(

[Buffy]

I wondered the same thing. I would think that you would want to pull a valve cover and see if the cam timing marks are lined up. If they are I would think you could do that. I am just going off what was said in the "Lost Timing Reference" video on the web. My passenger cover is only sitting on the head so I may back the pulley to the reference mark on the cover, pull off the cover and see if I see the cam timing marks.

[Scott Larson]

[QUOTE for all I care it can remain a mystery like that thing hovering in the back yard when I was a kid or the strange, strange pond with sides like glass in the woods near here....

OMG, you saw that too!!!

[psychos2]

I think the most confusing part for me now, is I sit here wondering what would have happened if I was to:

A) remove the tensioner
B) remove the original belt
C) turn the crankshaft pulley to move the notch to the right side, aligned with the mark on the oil pump housing, with the green line on the top of the pulley on the other side
D) put new belt on

Would my timing be OK or off? It's just so weird in my head because with the original belt still on, when I turned the crank shaft pulley to align the LH and RH camshaft marks, the notch was ALWAYS at the 9:00 o'clock position and the green line always lined up with mark on the oil pump, so I figured I had it right.

:(
from what has happened to some on this site and from what I have read about getting the cams back in time if the belt breaks.
1st make sure the marks are lined up before removing the belt.
2nd don not turn the cams without the belt being on. if you were to turn the cam 1 turn and put the belt on the cam timing would be off.There is a TSB about retiming the cams take a look at it and it will answer the question as to what would happen. shawn

[Scott Larson]

For what it's worth, you can turn the cam sprockets all you want, just don't lose track of how much you move them from the initial timing marks. I rotated both sprockets to tension the cam lobes against the valve springs to aid in setting the belt to correct time. (It eliminated the need for a helper or breaker bar and bungie cords to hold them from their 12 o'clock off-lobe position as per Barts write-up.) Set the belt to the correct position on both cam sprokets and then rotate the sprockets back to time, tensioning the belt in the process.

[psychos2]

For what it's worth, you can turn the cam sprockets all you want, just don't lose track of how much you move them from the initial timing marks. I rotated both sprockets to tension the cam lobes against the valve springs to aid in setting the belt to correct time. (It eliminated the need for a helper or breaker bar and bungie cords to hold them from their 12 o'clock off-lobe position as per Barts write-up.) Set the belt to the correct position on both cam sprokets and then rotate the sprockets back to time, tensioning the belt in the process.

If the cam is out of time it can take up to 9 full turns to put it back in time.So if you were to turn it 1 full turn the cam would be out of time.Yes you can turn it a little to line up the belt but I would not move it anymore than that unless you want to make alot more work for yourself. shawn

[tom4bren]

The "chocolate monkey" thing might just do that (:rotate:), so I always point people to the original how-to here:

http://www.nofuture.com/myvx/how-tos/tb/tbelt.htm

The above link is from my website, and if I make any revisions, you will see them there, but not in the PDF that Tom made of my original how-to back when I originally posted it. In fact I do think there are some minor changes on my site that ARE NOT in the PDF currently. Plus, I think my website is a better format and easier to follow. While the PDF is easier for people to find, I encourage everyone to visit the instructions on my site over the PDF.

Yerrrr Welcome!!!:)

I tried to be true to Bart's write up when I converted it to PDF (only took a little comic liberties). In retrospect, I should've added a hyperlink to his website so that any updates could be tracked. The PDF isn't supposed to do anything more than provide a copy for peeps to archive if they wish & print a throw-away copy to have in the garage whilst doing the repair.

Back on topic: Take the pix of the timing mark alignments to an authorized Isuzu repair facility (yes, those still exist) & find out if it appears out of spec to them.

IMHO, although the mark is obviously off slightly, it's not off by the amount that a 1 tooth adjustment on the belt would correct. If you adjust the belt by 1 tooth, the mark may actually be on the other side of the reference. This makes me think that it's a tensioner issue.

BTW, Chocolate Monkey:

[Ldub]

IMHO, although the mark is obviously off slightly, it's not off by the amount that a 1 tooth adjustment on the belt would correct. If you adjust the belt by 1 tooth, the mark may actually be on the other side of the reference. This makes me think that it's a tensioner issue.

Take a close look at the pic in question...the camera isn't lined up square with the end of the cam, giving the appearance that the reference mark is slightly off.
If the camera moved left slightly, so that the cam sprocket bolt was in line with center, everything would line up just right.

http://www.supermotors.net/getfile/805061/fullsize/left-bank-(driver).jpg

[MSHardeman]

When I helped Joh (VXorado) do his timing belt, his cam looked just like the picture above. We sat there and pondered whether his timing was actually off, or not, for a couple of hours. We moved the cams one tooth back and forth, but the marks never seemed to line up perfectly (they where that way with the old belt on too). In the end he left it, put it all back together, and it's been running just fine ever since.

[SlowPro48]

SlowPro, not at all.

Well that's good. Looked like people were getting DE-fensive so I thought uh-oh I guess that means I came across as O-ffensive. I never mean to offend anybody here* but sometimes it happens without my even trying. :sigho2:

Yeah I lined everything up just like Isuzu says to do it - with #2 at TDC and both cam pulleys lined up withe their marks. Then I took the old belt off and put the new one on. I have no idea where the dots and lines were on the old belt before I took it off. I couldn't see them but to be honest I didn't look that hard because I knew they didn't matter. All these marks are just there for you to verify that you have the right number of teeth between each pulley when you put the new belt on.

I think what's confusing the situation (for me at least) is that the cams don't turn at the same speed as the cam pulley** so you can't relate crank position to cam position easily just by looking at the pulley. One thing is for certain: although Isuzu says line the cam pulleys up with #2 piston at TDC, there is also a point in the rotation sequence where the cam pulleys are on their respective marks and #2 piston is at BDC - otherwise your engine would not be running.

If you did what you suggested - took the belt off and spun the crank 180 degrees and reinstalled the belt, your engine would not run. If you did the opposite - i.e., kept the crank where it was but spun all the cams 180 degrees (the cams themselves, not the cam pulley since it's not a 1:1 ratio) I think it would run just fine because of the wasted spark ignition system. I don't know if #2 is on the compression stroke or #5 is on the compression stroke when lined up like Isuzu says but it doesn't matter because both coils are fired by the same trigger so if you took the belt off and spun the cams around so as to swap the suck squeeze bang blow cycle from one cylinder to the other, the engine wouldn't miss a lick since it would still be getting spark when it was time to bang. If you spun the crank like you suggested though it would try to blow when the valves thought it was time to suck, suck when the valves thought it was time to squeeze, and blow when the valves and thought it was time to bang. It would also squeeze when the valves thought it was time to bang of course - but they wouldn't care - they're lazy - even when your engine is running properly they think squeezing and banging are the same thing - they just lay there with their springs extended, doing nothing - letting the ignition system do all the work...

Buffy's the one who could put this discussion to rest. Not only has he got the timing belt covers off at this very moment but also the valve covers so he can actually see everthing that's going on. Come on Buffy - dish out some info here - how many teeth on the cam drive gear and how many on the cam? How many teeth on the crank pulley and how many on the cam pulley? Line that baby up like Isuzu said to do it - then crank away and see how many turns it takes to get to Bart's configuration and how many turns it takes to get back to the Isuzu configuration. I bet Bart's is exactly half way through the cycle. Oh, and BTW Buffy - eat your Wheaties first! :luck:


*except for SpudBoy of course. But he's apparently too busy enjoying his white bread and crackers in Idaho to post here anymore. If he ever shows up again though I'll do my best to offend him because he and his ilk actively try to kill my joy (and yours too if you like to take your VX off-road). Oh, wait... maybe he's decided to diversify his honky self and move to NC - I think I see him in the background in this video! http://www.youtube.com/watch?v=roFB7bGCAgc

**I'm guessing they turn at 2/3 speed since it's a 60 degree V engine but yet you turn the left (even) bank pulley 90 degrees after it "springs" to reset the cams when you've lost timing due to belt breakage, etc. But then again if you check the illustrations in the shop manual it looks more like 3/4 speed based on the sizes of the gears so who knows. Either way the cams are under driven and that make it hard to visualize what's going on.

[Buffy]

OK guys.... I'll put on my peepers and do some counting this evening / weekend and see what I come up with! May have to wait until the morning so I can have TWO bowls of wheaties.:winky:

Update:
The crank gear has 26 teeth on it
The cam gear has 39 teeth

the rest of the counting will have to wait.... skeeters are vicious out there tonight!

[Buffy]

I installed all the new parts, checked and re-checked and double checked the timing marks. Pulled the pin, crossed my fingers and fired it up...... :madb: :upsetgray Nothing changed! The knock is still there just as before. Rev the motor and it stops briefly but will go back to the tapping/knocking. Any ideas?? It really doesn't sound like the engine. Do I remove the passenger head? Does anyone have a write-up on how to check the valve lash???

[Buffy]

After reading the service manual, I decided to pull the plugs on at a time and see if it caused the noise to change (per the manual). It did not change the sound of the knocking at all. Now here's the interesting part, after testing I refired the engine with all plugs connected and it ran quiet for about 30 seconds before the knocking began again.

[IndianaVX]

Well, I did something......posting for clarity.
Following barts how to, i rotated the crank several times watching all the marks
on the three pullys. Looking at bart's crank picture, the "dot" on the front
of the crank pulley lined up with the mark on the oil pump, and the cam marks lined up with marks on covers. I removed the tensionor, and the cams snapped like Bart said they would, but not WHERE he said they would. So I continued and got the heads removed, only to discover that #2 cylinder is at BDC!
So I've got to go thru the lost time service bulletin to get my cams where they need to be. Barts write up is good! So much better than the manual, but I got confused with the crank markings. Since heads are off, I'm going to turn the crank to 2 TDC and hope that the notch in back of crank pulley lines up with oil housing. Another confusing issue mentioned earlier, how do I know if I'm on a compressionstroke on #2?
Can I use a socket to spin the cam pulley? Thinking that I heard that was not good
thing to do.

[Ldub]

Have you seen these???

http://www.vehicross.info/modules.php?name=Content&file=viewarticle&id=14

http://www.vehicross.info/misc/timing_belt/timing2.wmv

http://www.vehicross.info/misc/timing_belt/timing.wmv

:_wrench:

[IndianaVX]

Lol, yeah, I think I've read every post on timing on vxinfo!
I was posting mor on the confusion of which mark lines up with the oil pump.
Manual says line up the notch on back of crank pulley. Barts how to lined up the "dot" on the front of crank pulley, which is what I did. However, when I did this, #2 was at the bottom of it's stroke, not TDC. And the marks lined up on head covers.
I will have to go by library tomorrow and watch those videos.
And I would NEVER consider you a wiserasshimer!

[Ldub]

I will have to go by library tomorrow and watch those videos.
And I would NEVER consider you a wiserasshimer!

Thanx D-man, those vids are Isuzu training vids...hope they'll give you some ansrs...:yesgray:

[nfpgasmask]

Yeah, there was some discussion some time ago about my instructions being sort of backwards. Which is very possible I guess, I just think that using my 'technique', you basically just keep everything in line and the timing stays the same. It still confuses me a little how it could work the way I did it if it is wrong.

:_huh: Bart

[MSHardeman]

Bart,

I followed your how-to to the letter and everything worked out for me too so you must have done something right. I do have to say, though, that when I lined everything up and took the timing belt off my cams snapped to 3 and 9, not noon as in your how-to. Doesn't really matter, I guess, as long as you line everything back up the way it's supposed to be.

IndianaVX, good luck with getting it all back together and running. Keep us updated.

[nfpgasmask]

Yeah, I dunno, my photos are how it worked out for me exactly, as I snapped pics and took notes all the way through. Weird, maybe it just depends on what position you remove the belt.

Bart

[IndianaVX]

Hardeman
My cams did the same thing by snapping to the wrong place.
Went and watched (more like memorized) the video on lost time.
That is the technique I will be using. With everything tore off,
I can watch the pistons, and heads off, I can see the internal marks on the cams.
I feel pretty good about getting it back together!
Again Bart, I hope you don't take my comments as being critical.
Just posting, so that the next guy won't be suprized, and will know a way out.

[MSHardeman]

IndianaVX,

I have to say that the cams snapping to 3 and 9 instead of noon as in Bart's how-to it scared the poop out of me, but once you get the new belt on (and I HIGHLY recommend the Isuzu belt) all you have to do is line up all of the lines on the belt with the notches and lines on the cams and crank and all should be well. I also read through the Isuzu "How to get your timing back" and though it was a little vague it did seem to have enough information to figure it out. Luckily I didn't have to use it. Once I got the new belt back on I turned the engine by hand to make sure the everything kept lining up.

In all honesty, once everything was back together I sat in the drivers seat for a good ten minutes with my hand on the key taking deep breaths and hoping that when I finally turned the key the VX would start up. It did and I heaved a BIG sigh of relief.

[IndianaVX]

After watching ,and memorizing the video, I was amazed at how easy it is to set the time back! Didn't take 2 minutes to time both heads... (of course, I haven't started the engine yet) but having everything tore down, it was easy to see the inside marks on the cams, and actually watch the cylinders move up and down. I meant to look and see where the internal marks were at after the "wrong snap" but was over anxious and went right to work as soon as I got there tonight, BUT I can officially say this....

When the notch on crank pully lines up with mark on oil pump,
The #2 is TDC. When the dot on front of crank pully is lined up with oil pump mark, #2 is BDC, the bottom of its stroke. Just so we REALLY know now!