Rough Running after Timing Belt Install

THIS INFORMATION BULLETIN OUTLINES THE PROPER STEPS TO INDEX THE CAMSHAFTS WITH THE CRANKSHAFT FOR VEHICLES EQUIPPED WITH DIRECT ATTACK DOHC 3.2L / 3.5L V6 ENGINE. IN THE EVENT THAT CAMSHAFT TIMING HAS BEEN DISRUPTED, DUE TO TIMING BELT BREAKAGE OR CAMSHAFTS / CRANKSHAFT BEING ROTATED WITHOUT A TIMING BELT, THIS IS IMPORTANT PRIOR TO TIMING BELT INSTALLATION. *TT
Make : ISUZU Model : VEHICROSS Year : 1999
Service Bulletin Num : SB0014S001 Date of Bulletin: FEB 01, 2000
NHTSA Item Number: 614146

i found this in a previous post. this is what i think the problem is.the cams are not indexed properly. if you sign up for alldata you can get the info you need.it is 24.95. or try to get info from a isuzu dealer. shawn

I couldn't find that SB at any of my (usually very good) sources.

I did find a number of references to "valve damage" in the event the camshafts and crankshaft were rotated independently. It's odd that valve damage can occur in a non-interference (free-running) engine however.

I also found some high-quality images of the correct method of 'capturing' the belt tensioner during timing belt replacement. I'll cross-reference my method with those methods already used in kpaske's efforts.

I looked up that TSB/NHTSA item number (614146) at the NHTSA web site, and it refers to the Child Safety Seats.

Make: ISUZU
Model: VEHICROSS
Year: 1999
Type: ANY
Service Bulletin Number: SB0014S001
NHTSA Item Number: 614146
Summary Description:
AMERICAN ISUZU MOTORS INC. IS PLEASED TO ANNOUNCE THE AVAILABILITY OF TOP TETHER CHILD RESTRAINT SEAT ANCHOR BRACKET KITS FOR CERTAIN ISUZU SPORT UTILITY VEHICLES. THE USE OF THIS ANCHOR BRACKET MAY BE NECESSARY WHEN INSTALLING CERTAIN CHILD SEATS, WHICH REQUIRE ANCHORING TO THE VEHICLE WITH A TOP TETHER STRAP. *TT

This is actually the one I think you meant to direct me to:

Make: ISUZU
Model: VEHICROSS
Year: 1999
Type: ANY
Service Bulletin Number: IB00S005
NHTSA Item Number: 614139
Summary Description:
THIS INFORMATION BULLETIN OUTLINES THE PROPER STEPS TO INDEX THE CAMSHAFTS WITH THE CRANKSHAFT FOR VEHICLES EQUIPPED WITH DIRECT ATTACK DOHC 3.2L / 3.5L V6 ENGINE. IN THE EVENT THAT CAMSHAFT TIMING HAS BEEN DISRUPTED, DUE TO TIMING BELT BREAKAGE OR CAMSHAFTS / CRANKSHAFT BEING ROTATED WITHOUT A TIMING BELT, THIS IS IMPORTANT PRIOR TO TIMING BELT INSTALLATION. *TT

I'll pass this info on to the shop working on my VX and see if they can get the information. Worse case scenario I can shell out the cash to NHTSA and get it myself. Maybe this will solve my problem once and for all. Thanks Pyschos2!

Mbeach - Can you give me some more info about this valve damage you speak of? That seems odd to me too, as I've always heard that even a timing belt breaking at 60+ mph cannot cause damage to a non-interference motor.

It really just added up to "...failure to follow these instructions can lead to valve damage..."

Sounds weird to me too.

Well, the TSB solved the problem. Thanks again to Psychos2 for bringing it to my attention.

A word of warning to anyone who attempts to replace their timing belt by themselves... I don't know if this problem was resolved in the 2000-2001 models, but apparently the Timing Belt Replacement procedure outlined in the Isuzu Shop Manual can create this problem. While the manual states that you should remove the timing belt and rotate the cam shafts and crank independently, the TSB explicitly states that this SHOULD NOT be done. The end result is having to remove the heads and realign the gears to reindex the cam shafts. Neither the mechanic nor the Isuzu technician he spoke to could really explain why this happens, but the bottom line is if you are going to do this yourself, the marks should all be lined up by rotating the crank BEFORE the belt is removed, and NOT rotated again until the new belt is back on and tensioned. I know some others have had success doing this themselves using the manual procedures, but I know I followed the directions correctly and it wound up costing me several days of my time, the cost of the parts, plus over $300 to have this mess fixed. You've been warned! ;Db;

Glad you got the problem solved! Just goes to show, we all can still find more to learn. ;)

Yep, glad to see you get through the nightmare!!

WOW...I got lucky...I rotated mine several times with the original belt still in place,Verified the belt was in the correct location (in time) removed the old belt and reinstalled the new one without moving anything. Thanks for the headsup and great to hear your on the road again....some of these post (like #45 and more) should be in the "how to" reminders....

I'm not usually "that kind of guy" but I just have to point this out:
I told you what was wrong, and what you needed to do exactly 8 days and 32 posts ago.
We can't sugarcoat every answer -be mindful of that fact whenever you (anyone) asks a question here. Sometimes the answers suck, but at least they are answers.

Mbeach -

Yes, you nailed it, 8 days and 32 posts ago... However, call me stubborn, but I didn't feel like you adequately explained how you came to that conclusion, which is why I continued to seek out answers. I'm not the type of guy, who if he can help it, will throw in the towel the first time he doesn't understand something. Unfortunately, I'm still not sure I understand the problem, but at least my VX is back on the road. Maybe your explanation was great, but I honestly didn't get it, considering the fact that I followed the manual's instructions to the letter. Am I a fool for wanting a second or third opinion before shelling out a few hundred bucks?

I did get the mechanic to give me the printouts of the TSB with the procedures for reindexing the cams, in case anyone ever runs into this problem again. When I have the chance, I'll scan them in and see if I can post them on the site, or put links to them on my web site. While I usually prefer to learn from other people's mistakes, this time hopefully someone can learn from mine. ;)

Thanks for being so gracious Kyle, my post really didn't have the tone that I would have preferred.

It's just nuts that the instructions that you were provided were SO wrong. That's really a problem. This thread should be cleaned up and stickied in the How-To section.

If the manual was wrong about the timing belt -what else could it be wrong about?

You wrote:
"I did get the mechanic to give me the printouts of the TSB with the procedures for reindexing the cams, in case anyone ever runs into this problem again. When I have the chance, I'll scan them in and see if I can post them on the site, or put links to them on my web site. While I usually prefer to learn from other people's mistakes, this time hopefully someone can learn from mine. "

After reading all 4 pages of this....you left out the punchline!!!!@#$#$$#@
Without showing the scan of the TSB.... can you at least reveal what the basic problem was?

Wadestock -

I can't explain it because neither I, nor even the mechanics that fixed it, really understand why this happens. But the bottom line is that if you change your timing belt, DO NOT under any circumstances, rotate the crank or cam pulleys with the belt off or it can seriously screw up your timing. The catch is, this is the exact opposite of what the ISUZU service manual says to do.

I'm moving out of my house tomorrow, or else I'd scan the TSB and post it. I might get to it Monday.

KP

mbeach, the fact that it is wrong in the manual is no suprise.and they do release TSB's for a reason.to correct something that they previously told you to do the wrong way.

kpaske, you are welcome, glad i could help. shawn

I replaced my belts at 120,134 miles but the dealer said they were in good shape. As the original owner since Aprill 99, except for tires, brakes, two radiator hoses and an EGR valve that's all I've done and it runs great! The VX has been very reliable. Never had an intake manifold problem or break down.

SOLUTION outlined:
I have around 222,000 miles on my VX and had previously replaced my belt twice with no issues. The 3rd time I recently replaced my belt, I ran into this issue. The FSM / CD have the procedure wrong. Apparently the 3rd time I did it, I deviated (or followed too closely) the instructions about rotating the cam sprockets up to 9 times to get them in the correct position... I found a video on youtube that outlines the correct phasing procedure.

In a nutshell. Line up your crank as indicated. Line up the notch on the passenger cam pulley as indicated, by rotating until the notch "snaps" into place at the 12'oclock position and lines up with the mark on the cyl head. BUT... BUT - the passenger pulley MUST be rotated until it "snaps" into place with the notch at the NINE o'CLOCK position. THEN rotate it an additional 90' clockwise until the notch lines up with the mark on the cylinder head. Now install the belt as indicated and all will be well.

And yes, the job goes MUCH faster the 2nd time through!

Hope this helps!

This was all covered in Bart's timing belt replacement write-up years ago, you do realize that you're responding to a thread that is over six years old...Just sayin'.:_confused

I didn't do a search, but figured even if it had been covered elsewhere - it couldn't hurt to add a final resolution here for those that find this first. More places it's mentioned, the better the odds of someone coming across it I figure.

:happyface

You've got a good point there, my bad...:slap:

Just to give a good tip -
Line up the crank to TDC using the timing marks on the out side of the oil pump which is a notch and the cut out on the inner side of the crank sprocket then mark the cams with tip-ex correction fluid - this way you know they are spot on - I also mark them in three places along with the crank sprocket - when removing the old belt push the long section of the belt in hard using a lever and pin the tensioner - then remove the tensioner - the cams will flick round once the tension is removed - but try to let them loose slowly using a spanner on the cam bolts - use bulldog clips or clothes pegs to hold the new belt in the right place on each cam and cable ties on spanners to hold them against the springing action works great - fit the tensioner and pulley assembly to the right torque and lever the new belt to release the pin on the hydraulic tensioner - turn over three times jobs done
cheers
Steve
PS removing the power steering pulley helps with removing the timing covers too