Timing Belt Parts

[nfpgasmask]

Man Bart that is a bummer, I am watching your thread closely because once you break trail here I'm gonna try it. I sure can't offer an answer but the possibilities that pop in my head is first of all someone may have installed a belt previously that is the right length but marked for a different engine. #2 It was installed with the left bank that far out of time.But then how could it run?#3 I seem to remember reading that the cam to crank ratio is such that it takes many revs to make the cam marks all come back around to the belt marks once it is rolled off of perfect. I'm just rambling here but If I were in Reno I'd buy you a cool one and tell you that tomorrow someone that knows is gonna solve this so kick back for the night. Good luck. John

Thanks, John. I really do hope someone chimes in who has done this. I was thinking the same thing, but I have owned my VX since 25k and I really can't imagine the timing belt was done or invaded prior to me doing so. But, anything is possible I suppose. Obviously, it is currently installed correctly, otherwise How would I have put 65,000 miles on it with no timing issues?

One possibility is that I need to keep turning it, but again, I have turned the crankshaft pulley an upwards of 10 times trying to get everything to line up. When I stopped, I was turning and it looked like it was almost there, about half an inch off. So I turned it one more time and then it was a half an inch off on the other side, so

Here's the real question, and maybe a stupid one, but I know nothing about engine timing, so here goes:

Why can't I align the marks on the belt with the marks on the housing, remove the belt, and put the new one on with the marks in the same exact spot? How could it POSSIBLY be off if I do it this way?

Maybe I am overthinking this and being uber paranoid, but I REALLY don't want to mess this up.

Bart

[Travelin2]

I see what you mean about changing the belt without moving anything shouldn't make a difference, but if you had to move the crank ever so slightly to get the cogs to align you wouldn't know which way you need to nudge it to be right without marks to go by. From what I read doing the belt change with the cams out of time gets considerably more complicated. I think that is the section where I read it takes a considerable amount of revs to make the marks "catch up". I would suggest leaving the belt on till you find your Guru. He'll surface. Can you hook your battery up so you can turn it over without plugs and have someone watch to see if the cam marks gain as it spins?

[Ascinder]

Why can't I align the marks on the belt with the marks on the housing, remove the belt, and put the new one on with the marks in the same exact spot? How could it POSSIBLY be off if I do it this way?

You can.

[Ldub]

I haven't done this yet, so I don't know how many attachment points can be accessed, BUT...

You could, in theory, wire all the pulleys together (while still being able to r & r the belt) so they can't move when the old belt comes off.
Look at what's there, any threaded holes in the block that could accept a bolt as an attachment point?

Get creative, post lots of pics...hope it goes well from here on...

[SoTxVx]

I have done this on 2.6L, 3.2L and 3.5L Troopers. The process is the same for the Vehicross.

If your engine was out time you would have known it. Engines just don't run right if this as little as one tooth off.

Don't worry about the marks on the old belt. The marks you need make sure are absolutely right are the cam pulleys to the heads and the crank pulley to the front cover. Get these marks as close to aligned as possible and remove the belt. With the belt off you can make the slight adjustments to the cam pulleys and crank to get it perfect before installing the new belt.

Once you get the new belt installed, turn the engine over by hand and make sure the marks stay lined up (again the pulleys to their reference marks). If they do, congratulations. If not, pull the belt align the marks and try again.

It is a tedious process but with any luck, you will nail the alignment on your first try.

[nfpgasmask]

You can.

Wow, up early I see! Gimme a call if you can come by.

You could, in theory, wire all the pulleys together (while still being able to r & r the belt) so they can't move when the old belt comes off. Look at what's there, any threaded holes in the block that could accept a bolt as an attachment point?

I see what you mean, but I haven't looked at that yet. I suppose it is a possibility.

Get creative, post lots of pics...hope it goes well from here on...

Oh yeah, gettin' creative! Yesterday I had to "make" an Isuzu J-tool so I could loosen the bolt on the crankshaft pulley! As for pics, I have 90 so far, and a huge write up on the radiator and timing belt is on deck.

Don't worry about the marks on the old belt. The marks you need make sure are absolutely right are the cam pulleys to the heads and the crank pulley to the front cover. Get these marks as close to aligned as possible and remove the belt. With the belt off you can make the slight adjustments to the cam pulleys and crank to get it perfect before installing the new belt. Once you get the new belt installed, turn the engine over by hand and make sure the marks stay lined up (again the pulleys to their reference marks). If they do, congratulations. If not, pull the belt align the marks and try again. It is a tedious process but with any luck, you will nail the alignment on your first try.

OK, so basically, I can ignore the marks on the belt and align the marks on the pulleys. One good thing, is that the marks on the camshaft pulleys align together. Meaning the left bank pulley, and the right bank pulley line up together at the same time. The crankshaft is confusing however since there is no reference mark on the crankshaft pulley itself, so far as I can see.

I guess I am just going to go for it, with the pulleys aligned with the marks on the housing and hope from there!

Bart

[SoTxVx]

Bart,

Take a close look at the crankshaft pulley. There should be a dot or a line that you will want to line up with the reference mark on the cover. If not, it will be the keyway on the crank lining up with the mark on the cover. Turn over the engine by hand until you get both cam pulleys lined up with their reference marks on the heads and I bet the crank keyway or pulley mark lines up with a mark on the front cover.

Install the new belt and make sure these marks all line up. It is a pain the arse sometimes to get it perfect, but nothing less than perfect is acceptable.

John