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1G Timing belt job leads to bent valves?

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kinders

Probationary Member
3
0
Feb 25, 2012
Buffalo, New York
Problem: Violent shaking from engine and generally no power throughout band.

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History:

Car was running fine but was due for a timing belt job ~ 163k

Grabbed all Mitsu OEM components for my 1g: Idler, Balancer, Tensioner pulleys, Balance belt, Timing belt, Hydraulic tensioner, even a friggen brand new harmonic balancer pulley (crank pulley) because the one on it was old and didn't want it to separate.

First off, I would like to say that I have researched until my eyes bleed, carry a shop manual, Haynes manual, and all special tools to do this job.

Not to mention this is my 3rd Talon so I'm not a completely new at this sort of thing and have been around the block with these beasts.
------------------------------------------------------------
Events leading to problem:

Start job timing belt change job, follow the VFAQ, Shop manual to a T taking off the belt and placing the new pulleys and belts on.

Made sure everything was lined up on timing marks properly:
  • Camshaft sprockets properly aligned
  • Oil pump sprocket properly aligned and balancer shaft in phase (checked back of engine bolt with a screw driver per VFAQ instructions and it tends to rotate counter clockwise at 12 o'clock)
  • Balancer shaft sprocket (front) lined up
  • Crankshaft sprocket lined up
Followed timing belt tension instructions using the two special tools.

Put everything back on.

Fired it up and everything was running nice except this very low pitched chirp coming from timing belt area. Figured it might have been something in the accessory belt section so I pulled off power steering and alternator belts to see if that fixed the chirp. No beans.

Because I tend to be very particular I figured that it was one of the pulley's and wanted to fix it. I suspected it was the idler pulley because I have a 90 GSX and I used a 92+ idler pulley like an idiot :rolleyes: but I did follow the instructions to put the correct shorter bolt and lock washer on it per VFAQ instructions.

I sat there and thought hmm, maybe I can get the idler pulley off to swap back on the old one and see if it resolves the chirping (wow I am really dumb I know). My rationale was that since the tension was all on the front side of the belt and after siting for a few hours the back side (idler pulley side) is slackened, I might be able to do it and short circuit having to redo the tensioning process.

So I went ahead and did it, and when I got the new idler off the cams rocked counter clockwise slightly (1/2 a tooth) but the belt did not jump any teeth or loose its position. Put the old pulley on and made sure everything was good and started it up. Still chirp but was running fine otherwise.

So now I knew it wasn't the idler and wanted to rip the whole damn belt off to find out exactly what it was. I was frustrated and tired and instead of making sure everything was at TDC I pulled the belt off with it possibly not at TDC. I proceeded to go through each pulley and check them one by one.

To make a long story short, I put everything back together after making sure all my pulleys were good and had to get everything at TDC with my T belt off. (rotated my cams by hand and brought all other timing marks on bottom end in position and double checked balancer shaft in phase)

Started her up and it is now shaking violently and lacks any power.

---------------------------------------------------------------------
Possible problems?

I believe I have it narrowed this down to 3 possible problems
  • Bad timing (camshaft sprocket off by a tooth)
  • Balancer shaft out of phase
  • Bent Valves
Bad timing:
I really feel the bad timing has been beaten out in the past 2 days because I have pulled off the t-belt and b-belt and triple quadruple quintuple checked my timing marks and even tried 1 tooth up on the exhaust cam to make sure damn well I wasn't rotating the exhaust side cam enough to line the marks up with the intake side cam.

I have taken the timing belt off so many times that I can do it now in like 30 mins flat.

Balancer Shaft Out of Phase:

Am I completely missing the boat on this or are the only thing to make sure your balancer shaft is in phase is by:
  • Making sure your balancer shaft sprocket is correctly lined up with arrow (the sprocket that is connected to your b-belt)
  • Oil pump sprocket it lined up with arrow and you do the test with the damn screw driver and 12 o'clock drop ccw test (sorry trying to be shorthand)
Could I have possible bent the valves when rotating the cams by hand or being a retard with the idler pulley? :banghead:

Do bent valves allow your car to run, although like crap and shake violently?

Thanks in advanced for the helpful info!!!
 
I have had several DSMs with timing belt breaking and so forth. Had one that ran for a few minutes then shes shut down to bent valves. Do it right replace all timing parts and make sure its all done properly or you'll be doing it again.

Bending valves by cranking by hand never had that issue here, just when my car was running.
 
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