Bad Engine Vibration. Please Help.
Thread Starter
Safety Car
Joined: Sep 2000
Posts: 4,679
Likes: 6
From: Charles Town WV
Bad Engine Vibration. Please Help.
I finally have my car back together after rebuilding the transmission. The transmission and shifter are so smooth it feels like a new car. Now the engine has a vibration. I'm hoping to god it's not the flywheel. Has anyone else experienced this? I really want to drive my car to Carlisle this year.
I don't know how turning a flywheel could take it out of balance.
I had the flywheel turned and installed a brand newCenterforce clutch.
The vibration is definitely rythmic out of balance vibration. Is it possible that the pressure plate is out of balance? Should I yank the thing back out and mount the pressure plate 180 degrees from where it is on the flywheel? I don't know how that could help since they are both supposed to be neutral balanced. The car did NOT do this before the clutch change. It behaves this way whether I have it engaged or disengaged.
I just cant thing of anything else that it could be. The harmonic balancer is fine.
I don't know how turning a flywheel could take it out of balance.
I had the flywheel turned and installed a brand newCenterforce clutch.
The vibration is definitely rythmic out of balance vibration. Is it possible that the pressure plate is out of balance? Should I yank the thing back out and mount the pressure plate 180 degrees from where it is on the flywheel? I don't know how that could help since they are both supposed to be neutral balanced. The car did NOT do this before the clutch change. It behaves this way whether I have it engaged or disengaged.
I just cant thing of anything else that it could be. The harmonic balancer is fine.
Thread Starter
Safety Car
Joined: Sep 2000
Posts: 4,679
Likes: 6
From: Charles Town WV
Re: Bad Engine Vibration. Please Help. (71coupe)
I'll note what RPM it starts happening at on my drive home tonight. I can't really feel it at idle, but it does feel rougher than it used to.
--
Steve
--
Steve
Melting Slicks
Joined: Jun 2001
Posts: 2,429
Likes: 14
From: CA
Re: Bad Engine Vibration. Please Help. (Steve Straus)
FYI - I did a trans r&r a few years ago on a pickup.
When I took it for a test drive, it had a bad vib.
It turns out that the distributor got tweeked when I pulled the trans
(it smacked the firewall) it caused a miss.
Just food for thought.
When I took it for a test drive, it had a bad vib.
It turns out that the distributor got tweeked when I pulled the trans
(it smacked the firewall) it caused a miss.
Just food for thought.
Thread Starter
Safety Car
Joined: Sep 2000
Posts: 4,679
Likes: 6
From: Charles Town WV
Re: Bad Engine Vibration. Please Help. (71coupe)
I know I didn't smack the distributor, I was VERY careful when jacking the engine. It doesn't feel like an igntion miss, it's a very out of balance feel.
Pro
Joined: Apr 2001
Posts: 605
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From: las vegas
Re: Bad Engine Vibration. Please Help. (Steve Straus)
Steve,I am sorry if I am telling you some thing that you already know.The flywheel can go on in any random position, but installed correctly you should have the extra hole in the flywheel aligned with the extra hole in the crankshaft.The extra hole is unthreaded. When I had my flywheel resurfaced I also had the new pressure plate balanced and indexed to the flywheel. Did you put in the needle bearing style pilot bushing? Folks do not seem to know that if you use that style of bushing bearing you need to index your bellhousing,as that style of bushing bearing requires a much closer alignment with the trans pilot shaft.There was an article in CHP on how to index the bellhousing, and I have seen the instructions on the internet also.The bronze style bushing does not require this indexing.I assume that you did not have a vibration before you did this work?
Thread Starter
Safety Car
Joined: Sep 2000
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From: Charles Town WV
Re: Bad Engine Vibration. Please Help. (a smith)
The extra hole in the flywheel is for a steel dowel pin. I have mine installed with the dowel pin, so I know it's on correctly.
I am running the bronze pilot bushing, but that's an excellent point you mention about the newer style pilot bearing.
And no, I did not have the vibration before I did this work.
I think I have a plan.
1) Take the whole damn thing back apart ::SIGH::
2) Take the flywheel and have the surface checked with a runout gauge to make sure it's true.
3) If the flywheel's surface is true, then have the whole works checked for balance
4) If it isn't true, then have it resurfaced, but this time I will *watch* them while they do it.
Am I missing anything?
--
Steve
I am running the bronze pilot bushing, but that's an excellent point you mention about the newer style pilot bearing.
And no, I did not have the vibration before I did this work.
I think I have a plan.
1) Take the whole damn thing back apart ::SIGH::
2) Take the flywheel and have the surface checked with a runout gauge to make sure it's true.
3) If the flywheel's surface is true, then have the whole works checked for balance
4) If it isn't true, then have it resurfaced, but this time I will *watch* them while they do it.
Am I missing anything?
--
Steve
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Thread Starter
Safety Car
Joined: Sep 2000
Posts: 4,679
Likes: 6
From: Charles Town WV
Re: Bad Engine Vibration. Please Help. (a smith)
I will bet that you find the pressure plate out of balance!
I'm going to find a driveline balancing shop tomorrow and take my driveshaft, flywheel and pressure plate and have them checked for balance and index. If the flywheel wasn't turned true I'll go back to the place that did it and demand my money back.
I really hope I have the car back together for Carlisle.
--
Steve
