Engine Vibration AFTER timing belt / water pump service - HELP!?!

[E39Alfa]

Hello again VR4 community,

Need help figuring out what’s causing my VR4 to start to vibrate at around 4-5k RPM range?

This issue arise after timing belt / water pump service done at a local shop. Car drives fine under 4k rpm BUT starts to vibrate after that. I returned the car back to the shop and explained to him the issue. He took another 2 days with the car and still can’t figure out the source of the issue. He initially thought it might be the motor mounts, not the case.

Any advice or recommendations will greatly be appreciated.

Thanks in advance

 

[gvr4ever]

He probably did the balance shaft belt wrong. I've never had it happen, but the balance shafts can rotate with the belt off and be out of phase. I can't remember if the rear or the front likes to rotate with a belt off, but that is likely it.

I'm no longer using the balance shafts, so it's way easier to only line up the timing belt marks.

 

[gvr4ever]

Step 21. click

 

[E39Alfa]

Awesome! Thanks man.

I will print off this for the shop so they can fix the issue.

 

[tektic]

They didn't know to set the balance shafts in the first place? If they don't take responsibility for this, I would certainly look for someone more qualified to do repairs in the future. Even then I'd probably still think twice about continued business with this mechanic.

 

[tektic]

This is how everybody heads blew up back in the mid 90s after their first timing belt jobs, not reading the manual, no one adjusted the timing tension pulley. I just wonder what yours is set at right now.

 

[slugsgomoo]

the funny thing is, when you have this vibration, it's almost always the rear shaft (oil pump) not the front shaft that's out of phase, since that mark is so obvious.

Since the oil pump can be 360* out of phase, it can look lined up and still be totally wrong. Take the plug off and check it with a screwdriver per the vfaq. You can probably get the car on a stand, and check that with ~15 minutes of work. /ubbthreads/images/graemlins/smile.gif

 

[E39Alfa]

Shop made the necessary adjustments and vibration is now gone.

Only issue now is the car idle low at times after engine is warm...

CAS probably??

 

[tektic]

With the car warmed up and the timing ground set you could try adjusting the idle set screw in the throttle body. Look at the manual for further details.

 

[andrew4g63]

Quoting E39Alfa:
Shop made the necessary adjustments and vibration is now gone.

Only issue now is the car idle low at times after engine is warm...

CAS probably??



Low idle at times? or all the time?
Cam timing be off can cause low idle.
Did it have low idle before the timing belt job?

 

[E39Alfa]

Low idle at times, we’ll happen experienced this in a few months now...ummm

Car idled fine before timing belt service.

AND NOW....

 

[E39Alfa]

MY MOTOR JUST WENT!!!

NO COMPRESSION in 3 of the cylinders!!!

Here is the series of events that uncovered this mess...

Took the car to another shop (not the shop that did the TB service, of course) to convert my AC to 134A. Serviced and worked fine until AC went out 3 weeks later.

Returned to car to the same shop to find out why my AC stop working after just recently converting to 134A. Shop tested for leaks and what not and found out that the compression clutch was not engaging. FML!!! Just sent $700+ to convert... NOW THIS??

OK fine, I guess no AC for me for the rest of the summer, I can live with that, right??

About a week after that I started to hear a squeaking noise coming from the engine bay... after further investigation found out the belt from the AC compression was loose and part was wedged in the corner of the engine block where the TB cover is.

WTF / HTF was my initial reaction.

Looking down further on the crank pulley, there was only one belt on there. The AC belt seemed to came off the crank pulley and was wedged in a corner. And with the engine running, that was to source if all the squeaking noise with a very slow rotation of the AC belt.

At this point I’m thinking WTF did this shop do when they did my AC service??? So I decided to drive the car back to there shop Sunday evening so they can look at it first think Monday morning.

Well on the 5 mile trip to the shop with my wife tailing me, the car just suddenly died on me at a stop light with no warning sign such as loss of power or engine hesitation/vibration. It just died not even a football field away from the shop.

So after a few F bombs, I gathered myself and popped the hood and saw that now the AC belt was no longer visible in the engine bay. Must have fell to the bottom of engine tray or something. Whatever. So we hook the car with some ratchet straps and pulled it to shop

Shop did their investigation and called me with news that I have bigger problems than the AC compressor and belt...

They did a compression test on the car and received NO COMPRESSION in the first 3 cylinders and didn’t even bother to do the 4th. And that this issue had nothing to do with the AC service that they did because they didn’t touch the AC belt or tension while they did their service. They said that this way an internal issue with the engine at this point. They also took the top portion of the TB cover off and noticed that the belt was starting to shred a bit.

So thinking back to the shop that did my TB service and all the issues they had with it... could it be that my timing was not set correctly amongst other things???


Man I'm lost at this point. Where to start with all this mess???

GVR4 Community, Your Opinion and Expertise is Needed!!!

 

[CutlassJim]

Sounds like the AC belt made it's way into the timing belt via the crank pulley.

Not to be too coarse but driving the car while there was clearly an issue was a terribly bad idea. Since the car ran for so long the timing belt job was probably done correctly the second time around. As soon as you saw the AC belt shredded and still sitting there and choose to continue driving the car that way you assumed responsibility for the potential outcome from it.

You %100 have a bunch of bent valves. Head will need to be removed and rebuilt. I'm assuming since you didn't do the timing belt in the first place you are either incredibly strapped for time or don't posses the skills/tools to perform the work. If you are having a shop fix this expect to pay between $1400-2000.

If you can find a local DSM/GVR4 enthusiast to help you it could cost around $500 and be done in a long day.

 

[fuel]

I'm guessing it's one of three things:

1) The first shop who messed up your timing belt job did something that damaged the belt - wrong bolts in the wrong place, belt tension too loose etc

2) Your crank pulley split (this happens due to age and is a common problem) and the excessive vibration with the crank not being dampened caused further damage after prolonged driving with it in this state

3) a combination of both, or none at all and I'm just talking BS.

 

[gvr4ever]

It's also possible that the front balance shaft froze up, getting the balance shaft belt tangled in the timing belt causing a timing belt failure. I've never heard of a AC belt causing the problem, but anything is possible. I'd image the drag / resistance started from some place else and some how trashed the AC belt. That's just a guess, but more likely. IMO.

The crank pulley should have been replaced with the timing belt, or at least inspected.

If you really like the car, don't give up just yet. If you take your time to look around, you could likely find a quality shop that can fix it without breaking the bank. In the future, it's not a good ideal to drive any car when it sounds, or looks like something is really off. Just pull over and get it towed. Just chalk that up to a life lesson. Pulling over sooner probably would have saved the head.

 

[E39Alfa]

Nail on the head with opinion # 2 with the crank pulley. It failed!

 

[E39Alfa]

I honestly didn’t know to replace the crank pulley at the time of TB service... it will cost me big time.

Guess now I’ll just build the top end

 

[E39Alfa]

Definitely right that I shouldn’t have drove the car knowing that it wasn’t at 100%... lesson learned

 

[CutlassJim]

Quoting E39Alfa:
Nail on the head with opinion # 2 with the crank pulley. It failed!



HOLY HECK!

Are we talking about the crank pulley as in the toothed gear for the timing belt or the crank pulley as in the harmonic balancer that the accessory belts ride on?

 

[gvr4ever]

Crank pulley, harmonic balancer failure, usually just leaves you stranded, I thought. Unless it failed in away that it cut into the lower timing belt cover.

Double check the front balance shaft belt.