Engine Vibration
Instructor
Joined: Nov 2005
Posts: 228
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From: Austin Texas
For what it's worth, I had an engine vibration that I was starting to think might be internal. I was using a clutch and flywheel that were both supposed to be zero balanced from the factory. I finally tore the car apart and took the clutch and flywheel to a machine shop. Sure enough, the pressure plate was 20 grams out. Had it rebalanced, and now the motor revs smooth as butter.
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Race Director
Joined: Mar 2004
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From: Fort Wayne IN
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For what it's worth, I had an engine vibration that I was starting to think might be internal. I was using a clutch and flywheel that were both supposed to be zero balanced from the factory. I finally tore the car apart and took the clutch and flywheel to a machine shop. Sure enough, the pressure plate was 20 grams out. Had it rebalanced, and now the motor revs smooth as butter.
Race Director
Joined: May 2005
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From: West Norriton PA
St. Jude Donor '08
I'd like to think that's going to be my problem but the issue at hand is that the clutch on my car was already in use on my original motor and the clutch went from box to car. Unless some amazingly freakish coincidence caused the clutch to be out of balance at the same points and weight as the stock flywheel if it had weights added, I don't see the clutch being the issue. My main reason for tearing it all apart is to check the pilot bearing, and if that turns out good I'm going to run the car without the TQ tube attached and see if the vibration is still there. If it is, I'm going to pull the clutch and send it for balancing so I KNOW the flywheel has a neutral balance, then I'm going to reattache the flywheel and check again. If it continues, pretty much solidifies that it's an internal issue.
Just a heads up, but I believe that the Textralia's are neutral balanced as a unit and not seperate components, that's why there is mark on them from the factory showing the alignment point so that you put it back together correctly to keep it in balance.
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
I'd like to think that's going to be my problem but the issue at hand is that the clutch on my car was already in use on my original motor and the clutch went from box to car. Unless some amazingly freakish coincidence caused the clutch to be out of balance at the same points and weight as the stock flywheel if it had weights added, I don't see the clutch being the issue. My main reason for tearing it all apart is to check the pilot bearing, and if that turns out good I'm going to run the car without the TQ tube attached and see if the vibration is still there. If it is, I'm going to pull the clutch and send it for balancing so I KNOW the flywheel has a neutral balance, then I'm going to reattache the flywheel and check again. If it continues, pretty much solidifies that it's an internal issue.
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Race Director
Joined: Mar 2004
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From: Fort Wayne IN
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They are marketed and sold as a balanced unit, and I haven't seen any reports of one being out of balance. Not familiar with the mark you're talking about, but know that the way that the dowel pins are set up that you can only put it together one way.
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
That is correct, and exactly how my OZ-700 was.
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Race Director
Joined: Mar 2004
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From: Fort Wayne IN
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I found one other thing last night it could possibly be. Apparently the Gen III/IV motors are VERY sensitive to how the flywheel is torqued down. If not done in a very specific manner it might not seat right. Another thing to check I guess.
At this point I'm almost feeling like I should do something while I'm in here, like upgrade the clutch or something. Money however, dictates otherwise.
At this point I'm almost feeling like I should do something while I'm in here, like upgrade the clutch or something. Money however, dictates otherwise.
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Burning Brakes
Joined: May 2008
Posts: 1,147
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From: Mohegan Lake New York
Totally interesting thread,got some pretty sharp minds responding to your prob.,can't add anything except to say it always seems when a car fights you this hard in the end it's worth it,in that it runs better than expected,like the car is saying "you want me to run hard ,well you're gonna have to work for it" don't get discouraged,from the input you got they like myself have sometime had a build that frustrated and fought you every inch of the way I certainly have had my share .....GOOD LUCK
Instructor
Joined: Nov 2005
Posts: 228
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From: Austin Texas
I found one other thing last night it could possibly be. Apparently the Gen III/IV motors are VERY sensitive to how the flywheel is torqued down. If not done in a very specific manner it might not seat right. Another thing to check I guess.
At this point I'm almost feeling like I should do something while I'm in here, like upgrade the clutch or something. Money however, dictates otherwise.
At this point I'm almost feeling like I should do something while I'm in here, like upgrade the clutch or something. Money however, dictates otherwise.
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Race Director
Joined: Mar 2004
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From: Fort Wayne IN
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Yeah, the manual says to tighten the bolts down incrimentally in three passes, normal star pattern. I've always done it that way, but it seems like you would have to really screw up to get the flywheel bound up at an off angle. Even though it seems unlikely, I'd still take the clutch and flywheel to a machine shop and at least have them check the balance... it's quick and cheap, and you might get lucky. Peace of mind if nothing else.
I have to laugh at how I plan to run the car. No belts, no steering rack, no wheels, no downpipes, wastegates, or exhaust.........just funny to me.
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Race Director
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From: Fort Wayne IN
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Pilot bearing is fine. Not going to bother running the car without the TQ tube. Going straight for the clutch pull and balance. If that doesn't do it........insert record length of expletives here.
Oh....btw.......doing the tq tube on your own SUCKS. I don't have a tranny jack so I ended up with both my hydraulic jacks under the rear cradle to keep it's fore/aft shifting to a minimum, and put my shop stool under the front of the tube. Rolled right out.
Oh....btw.......doing the tq tube on your own SUCKS. I don't have a tranny jack so I ended up with both my hydraulic jacks under the rear cradle to keep it's fore/aft shifting to a minimum, and put my shop stool under the front of the tube. Rolled right out.
Race Director
Joined: May 2005
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From: West Norriton PA
St. Jude Donor '08
Pilot bearing is fine. Not going to bother running the car without the TQ tube. Going straight for the clutch pull and balance. If that doesn't do it........insert record length of expletives here.
Oh....btw.......doing the tq tube on your own SUCKS. I don't have a tranny jack so I ended up with both my hydraulic jacks under the rear cradle to keep it's fore/aft shifting to a minimum, and put my shop stool under the front of the tube. Rolled right out.
Oh....btw.......doing the tq tube on your own SUCKS. I don't have a tranny jack so I ended up with both my hydraulic jacks under the rear cradle to keep it's fore/aft shifting to a minimum, and put my shop stool under the front of the tube. Rolled right out.
I don't think it's the clutch either based on the fact that it worked fine before the swap.
My guess is that it's the motor. I hope you get things worked out.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
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From: NS
Man I feel your pain. This sounds very familiar to me. We had an oval track race engine once with a slight vibration just as you described. After a few checks we decided it wasn't bad enough to worry about and ran the engine that season. In the last race of the year it knocked the oil pump pick up off, even broke the tack weld we had holding it in place. Also destroyed the harmonic balancer over the season. Crank bearings were toast due to lack of oil and vibration. It's amazing how much grief a simple vibration, barely noticeable, can cause down the road. In our case it was internal balance just off slightly. Oval track racing so the engine always operated at high RPM which probably accelerated the failure.
Based on what you are saying, my guess would be internal balance.
Based on what you are saying, my guess would be internal balance.
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Race Director
Joined: Mar 2004
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From: Fort Wayne IN
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So if it turns out to be internal, what are my odds of recouping money previously invested with peripherals and installation I paid for that I will have to redo??? TSP has already said they won't cover that, but for an engine that had issues from day 1, I think I've got a pretty good case to sway them.
Race Director
Joined: May 2005
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From: West Norriton PA
St. Jude Donor '08
So if it turns out to be internal, what are my odds of recouping money previously invested with peripherals and installation I paid for that I will have to redo??? TSP has already said they won't cover that, but for an engine that had issues from day 1, I think I've got a pretty good case to sway them.
If it's TSP fault (i.e. motor unbalanced), then they should pay for all of the labor and parts to fix the problem.
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Race Director
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From: Fort Wayne IN
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It's going to be a few days before I really know for sure what's going on. My next opportunity to get the clutch out of the car will be Thursday night. Today I'm going to call around to try to find a local shop that can spin balance a clutch. So if I get lucky I'll be dropping the clutch off on Friday.
While that's being done, I'll probably address taking the TQ tube apart this weekend to check the bushings just in case. Worst case scenario I spend ~$100 to get new ones as a preventative measure. Don't think the TQ tube is bent or way out of whack though becuase the pilot bearing looks immaculate.
Gotta pick up a remote bleeder while I'm at it. There's no way I want to have to drop everything again so I'm trying to address everything I can while the driveline is out.
I know I haven't said it before, but I really appreciate everyone's help with this. I really do.
While that's being done, I'll probably address taking the TQ tube apart this weekend to check the bushings just in case. Worst case scenario I spend ~$100 to get new ones as a preventative measure. Don't think the TQ tube is bent or way out of whack though becuase the pilot bearing looks immaculate.
Gotta pick up a remote bleeder while I'm at it. There's no way I want to have to drop everything again so I'm trying to address everything I can while the driveline is out.
I know I haven't said it before, but I really appreciate everyone's help with this. I really do.
Tech Contributor
Joined: May 2008
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From: Howell Michigan
St. Jude Donor '09-'10-'11
If the issue ends up being internal balance, what is your next step? If you had someone near with balancing equipment there is a good chance that the imbalance could be corrected with the engine in place.
Thanks for posting your progress, as others have point out, it makes for an interesting read and I'm sure it can help others identify balance issues.
As far as doing all the work yourself, that can really suck as you point out. No other vett owners near you to give a hand? I hope it all works out for you which I'm confident it will.
Thanks for posting your progress, as others have point out, it makes for an interesting read and I'm sure it can help others identify balance issues.
As far as doing all the work yourself, that can really suck as you point out. No other vett owners near you to give a hand? I hope it all works out for you which I'm confident it will.
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Race Director
Joined: Mar 2004
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From: Fort Wayne IN
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If the issue ends up being internal balance, what is your next step? If you had someone near with balancing equipment there is a good chance that the imbalance could be corrected with the engine in place.
Thanks for posting your progress, as others have point out, it makes for an interesting read and I'm sure it can help others identify balance issues.
Thanks for posting your progress, as others have point out, it makes for an interesting read and I'm sure it can help others identify balance issues.
As far as doing all the work yourself, that can really suck as you point out. No other vett owners near you to give a hand? I hope it all works out for you which I'm confident it will.