Automotive Forums

The Story....

Driving home rather aggressively (pedal to the metal) and the car starts to vibrate from the front end.  I get home and pull the timing belt cover off and see that the balance shaft belt is damaged (missing all teeth).  I think I found the problem.  I replaced the balance shaft belt, timing belt, and all other belts.  Head gasket, exhaust manifold gasket, intake manifold gasket, and valve cover gasket.  I also took the oil pump assembly off (I did this after the belt replacement did not fix the problem.)  That assembly was good.  So, after all that, the car vibrates at around 3000 rpms when driving.  The motor also vibrates in park. Not sure when it does it because I am under the hood when I do it.  I also replaced the rear motor mount thinking it was that.  

Now, I'm stuck.  I took it to a shop who drove it, and they think it was either the motor mount, or the axle.  The axles are fine.  The only other thing I can think of is that it is the front motor mount.  

I have taken this thing apart 4 times and make sure the crank, cam, and both balance shafts are aligned properly.  I feel like a master at this, but I'm still in the dark.

Please help....much thanks in advance.
-Blake  

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go here to asked you questions , someone will respone in 10 minutes...try it.  

On my 90 Accord Coupe EX, I got my timing belt and water pump replaced at a body shop (big mistake)at the same time as they were doing the wheel well rust. I experienced the exact same symptoms as you driving home. I took it to the Honda dealership and they said they've seen it before - these symptoms are the result of a common mistake other mechanics make on this car. Other mechanics are not aware that there is a balancer belt kit with tensioner that must be installed when the timing belt is done (and once installed it must be adjusted properly).
I am taking it to the dealer tomorrow to get it done right.  

My initial problem was that the balance belt was bad.  All the teeth on the belt were gone.  I am so frustrated with this car. I'm ready to buy another motor.  There are 2 balance shafts and they are both timed properly, but my motor is still messed up.  I think I have a bad bearing that is in that area.  

I'm interested to find out if this has fixed your problem.

Good luck,
Blake  

Very strange. However, u say all the teeth on the belt were gone. This strongly tells me a shaft locked up. This belt is under much less stress than the main camshaft timing belt and I've only ever seen the main belt strip teeth when a water pump bearing destroyed itself and made the teeth on the Water Pump pulley rip into the belt. I replaced the balancer belt on my Prelude at 100K and there was absolutley no perceivable wear on the old belt regards any of it's teeth. Did the front and rear balancer shafts turn smoothly and freely by hand when u had the belt off? Any side ways play on their toothed cams. Did the pulleys on both shaft rotate squarely & not bent and wobblying when turned? I would suspect a bad bearing on one of the shafts. U could try running the engine with the belt removed. The engine will obviuosly vibrate a little at all speeds without balance in place but u should be able to see if it's not noticeably stronger at the 3000rpm mark.

Good Luck!