Non Interferece Engine ... Final answer

[tom4bren]

Whilst I have the heads off'n Boy's Ebony, I looked. Our engines are in fact non-interference.

Just by eyeball (wouldn't know how to use a caliper even if I owned one), the piston only comes within about 1/4 inch of the top of the cylendar. Rotating the camshaft till one of the valves opens alla way ... it protrudes into the cylendar less than 1/4 inch.

That's good enough for me ... which is good since I have no confidence that we didn't lose our timing reference when we pulled the heads.

[nocturnalVX]

Good looking into this for us! Settled once n fer all.

[samneil2000]

"like"

[blacksambo]

Nothing like good-old visual evidence. Thanks.

[Gizmo42]

A big part of the confusion is that the manuals are wrong on how to time the cam shafts. So after a belt break it gets timed wrong, runs like crap if at all, and a compression check looks like a bent valve. I imagine a lot of perfectly good engines/heads were replaced by mechanics that didnt know any better.

[michigan hooligans]

Any info on how to change a t belt im doing my belt soon. I bought this 1999 vx from a isuzu engineer and he says it is a interferece motor. Not saying he is right but not taking any chance. Any info and pics would help alot. I also need a good book on the vehicross.

[tom4bren]

Any info on how to change a t belt im doing my belt soon. I bought this 1999 vx from a isuzu engineer and he says it is a interferece motor. Not saying he is right but not taking any chance. Any info and pics would help alot. I also need a good book on the vehicross.

Don't forget to replace your water pump whilst you are in there. Murphy drives a VX & his laws dictate that your pump will go out within 300 miles of your timing belt change if you don't.

Also, make sure you get a complete kit. The tensioner should be replaced along with your belt. They have a tendacy to go bad too.

Bart wrote a How2 on the timing belt change. I'll see if I can find a link for you.

The shop manual is also available. I'll see if I can find that link too.

Here's the link to Bart's Timing Belt Replacement How2:

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

Look here for Shop Manuals:

http://www.vehicross.info/modules.php?name=Downloads&file=viewcategory&cid=3

[michigan hooligans]

I just found this http://www.youtube.com/watch?v=kjhNOVl1Tcc And it sounds to me like it is a interference motor.

[michigan hooligans]

Thanks tom4bren this helps alot. I do know to get a kit. I was a wreanch 7 years about 18 years ago. I could just mark everything and go at it but this has 2 cams. and some engines have little tricks to them like make sure you gasket seal this or that so all i can find out is helpfull.

[tom4bren]

"... it sounds to me like it is a interference motor."


Hence the need to check it for meself when I had the heads off. We've been getting conflicting information.

Like I said earlier, the eyeball inspection that I did is good enough for me ... use that tidbit of info at your own discretion.



"Thanks tom4bren this helps alot."

Don't thank me. nfpgasmask is the one to thank. I just converted his write-up to pdf & posted it to the How2 section.

[Gizmo42]

Here is the procedure that Jerry Lemond (Isuzu Guru) says to use for timing the 3.2/3.5


OK STEVE LETS DO IT THIS WAY , FORGET THE MANUAL , YOU CAN USE IT WIPE YOUR HANDS WITH WHEN YOU GET THRU, TURN THE CRANKSHAFT SO THAT THE KEYWAY IN THE CRANKSHAFT IS SET AT 3.0CLOCK THERE IS A LINE ON THE OIL PUMP TO LINE THIS ONE UP WITH, THIS ONE IS EASY THE SLASH MARK ON THE EDGE OF THE LOWER TIMING PULLEY GOES OVER TO THE 9.0 CLOCK POSITION, NOW ROTATE THE CAM PULLEY ON THE RT BANK CLOCKWISE AND IT WIL GO THUMP THUMP MAYBE 5-7 TURNS BEFORE IT WILL LINE UP , DEPENSD ON WHER IT IS NOW , LINE UP THE TIMING MARK ON THE PULLEY WITH THE MARK ON THE VLV CVR IT WILL BE RIGHT BETWEEN THE TWO SEALS IN FRT ALLSO THE KEY WAY IN THE CAM GEAR CAN BE USED AND IT SHOULD LINE UP WITH THE MARK ON THE PULLEY,, NOW ON THE LFT BANKTAKE A CLOSE LOOK AT THE TIMING MARK ON THE VLV CVR SAME SPOT AS ON THE RT BANK, LOOK TO THE LEFT OF THIS MARK FOR A MARK ON THE CYL HEAD ITSELF NOW ROTATE THE CAM GEAR AROUND WHAT EVER NO OF TURNS IT TAKES TO GET THE MARK TO LINE UP, WITH THE MARK ON THE GEAR AND THE CYL HEAD OK ,, NOW ROTATE THE SAME GEAR CLOCKWISE UNTILL THE CAM GEAR MARK LINES UP WITH THE MARK ON THE VLV CVR , THE REASON YOU HAVE TO TURN THES THINGS SO MANY TIMES , IS THE CRANK SHAFT OBVISOULY HAS TO TURN TWICE FOR EVERY CAM SHAFT TURN CORRECT WELL ON THESE ENGS THE RATIO FOR THE CAM TO CRANK IS NOT 2.1 IT IS 1.57 TO ONE , HOW CAN THAT BE , THE RATIO IS PICKED BACK UP INSIDE THE HEAD WITH THE CAM GEARS INSIDE THE HEAD TO BRING IT BACK TO THE 2.1 CAM TO CRANK ,, THIS WAS DONE TO LOWER THE CYL HEAD HEIGHT , SOMETIME TAKE A LOOK AT THE OVERALL HEIGHT OF THIS ENG COMPARED TO THE OLD ER 3.2 SOHC OR THE DOHC ENG THIS ENG IS ALLMOST 3INCHES SHORTER IN HEIGHT , THERE ARE NO ROCKER ARMS NOLIFTERS NO ROCKER SHAFTS , THE CAMS RUN RIGHT ON TOP OF THE VLV STEM THRU A BUCKET TYP SDJUSTER THAT SITS ON TOP OF THE CAMSHAFT, NO A NEW DESIGN BY ANY MEANS BEEN AROUND FOR EVER BUT NOT IN THIS TYPE OF AN ENG ,,, ANYWAY NOW PUT THE BELT BACKON AND RELEAS THE TENSIONER AND YOU SHOULD BE IN GOOD SHAPE , BY THE WAY THESE ENGS WILL RUN ON 3 CYL ON ONE BANK RELATIVELY SMOOTH. JERRY

[Leon R]

I do not trust people shout all the time :). As for "Isuzu engineer" who said it was an interference engine, what exactly was his job in US? I am pretty sure engines were designed in Japan, in the 80's and then upgraded to 3.5 in the 90's.

I thought it was a well established fact that it was an non-interference engine?

[bigblock8396375]

Put a piece of clay on the piston top at TDC,rotate the cams remove head and see what the thickness of the clay is.

[Gizmo42]

[quote]I do not trust people shout all the time[/qoute]

Normally I dont either but we let Jerry get away with it because he is legally blind and its easier for him. He trained Isuzu mechanics for over 20 years and knows absolutely every thing about Isuzus.

[JoFotoz]

X2..


[quote]I do not trust people shout all the time[/qoute]

Normally I dont either but we let Jerry get away with it because he is legally blind and its easier for him. He trained Isuzu mechanics for over 20 years and knows absolutely every thing about Isuzus.

:thumbup:

Jo

[Espritmike]

I looked into it also- non interference. Now, the books say they are but I think they say that on most motors, probably to protect liabilties ! I did hear the vin "V" motors n the 2004 DI 3.5 Axioms and Rodeos are interference though. Easy to see- different timing covers