engine vibration from improper installation of harmonic balancer?
Thread Starter
Registered User
Joined: Sep 2003
Posts: 627
From: Edmonton, AB, Canada
Re: engine vibration from improper installation of harmonic balancer?
The performance shop removed the transmission and took the clutch, pressure plate and flywheel to a machine shop and they said the balance was dead on and they could do nothing to improve it. Does this rule out the clutch balance as a cause for the vibration? Is this entire assembly supposed to be imbalaced in order to work with the rest of the transmission and motor? Im wondering what else can be done to nail this down.
Waylow, exhaust doesnt pop in idle. It does every now and then if im coasting down a hill in gear, but its gotta be rich because of the cam. Plugs, opti, and plug wires are all brand new and car runs strong - i dont think its running on cylinders.
Waylow, exhaust doesnt pop in idle. It does every now and then if im coasting down a hill in gear, but its gotta be rich because of the cam. Plugs, opti, and plug wires are all brand new and car runs strong - i dont think its running on cylinders.
Registered User
Joined: Dec 1969
Posts: 165
From: Tallahassee, FL USA
Re: engine vibration from improper installation of harmonic balancer?
Originally Posted by med_reject
The performance shop removed the transmission and took the clutch, pressure plate and flywheel to a machine shop and they said the balance was dead on and they could do nothing to improve it.
So, I would not expect the flywheel to be balanced by itself -- I would expect the flywheel to show an unbalanced condition witout the rotating assembly in the engine.
I'm told the reason the one-piece rear seal engines need to be externally balanced by the flywheel is the flange on the crankshaft with the non-one-piece engines provided the balance -- but since the flange is no longer there, the balance has to be provided by the flywheel.
Tom Piper
Thread Starter
Registered User
Joined: Sep 2003
Posts: 627
From: Edmonton, AB, Canada
Re: engine vibration from improper installation of harmonic balancer?
so this means that new flywheel and old flywheel must be taken to the machine shop so that the balance (or imbalance) in them is the same?
Registered User
Joined: Aug 2002
Posts: 4,676
From: Melvindale, MI, US
Re: engine vibration from improper installation of harmonic balancer?
Originally Posted by med_reject
so this means that new flywheel and old flywheel must be taken to the machine shop so that the balance (or imbalance) in them is the same?
Thread Starter
Registered User
Joined: Sep 2003
Posts: 627
From: Edmonton, AB, Canada
Re: engine vibration from improper installation of harmonic balancer?
wow. Thanks guys. Does it matter if I use the flexplate from my auto or a flywheel from an lt1 t56 to balance the spec flywheel? Im thinking it should not matter either way as the motors for both cars are the same.
Registered User
Joined: Mar 2005
Posts: 51
From: Texas
Re: engine vibration from improper installation of harmonic balancer?
Originally Posted by med_reject
Every since my cam and tranny swap, my car has been vibrating like hell. I attributed that to the big cam, gm847. The mechanic who was doing my opti and plug wire swap said the harmonic balancer was not lined up right, and this is causing the motor to vibrate. He didnt know the correct way to put it together because he said there was no tooth markings or anything. He suggested I go to a dealer to get it rebalanced.
Searching on this site has left me confused. Threads state that the balancer cannot be put on wrong cuz they only go on one way. The belt itself looks fine when the motor is running, but the engine definitely vibrates, shakes the car at idle and shakes my eyes out of their sockets at wot. I thoguht it could be a flywheel balancing issue, but if its the harmonic balancer that should be very simple.
Anyone know how to put that thing on properly?
1995 t56 TA, hurst shifter, spec stage 2 clutch, 3.23 gears, ported stock heads, gm847 cam, CAI, Granatelli MAF sensor, 58mm BBK TB, Hooker shorties and catback (gutted), lt4 knock module. Awaiting 4.11s.
Searching on this site has left me confused. Threads state that the balancer cannot be put on wrong cuz they only go on one way. The belt itself looks fine when the motor is running, but the engine definitely vibrates, shakes the car at idle and shakes my eyes out of their sockets at wot. I thoguht it could be a flywheel balancing issue, but if its the harmonic balancer that should be very simple.
Anyone know how to put that thing on properly?
1995 t56 TA, hurst shifter, spec stage 2 clutch, 3.23 gears, ported stock heads, gm847 cam, CAI, Granatelli MAF sensor, 58mm BBK TB, Hooker shorties and catback (gutted), lt4 knock module. Awaiting 4.11s.
Maybe the reason you cant find anything wrong that would cause the viberation, because its something that you cant really check? like the main berrings.
I hope that's not the problem, for both our sakes.
Thread Starter
Registered User
Joined: Sep 2003
Posts: 627
From: Edmonton, AB, Canada
Re: engine vibration from improper installation of harmonic balancer?
The car only has 55k miles on it, and was fine with the auto. The spec flywheel is neutrally balanced, which is not right so that needs to be worked on regardless (mechanic is still working on that).
Would an lt1 flywheel be fine to put in there with the spec clutch and pressure plate? If those things are neutrally balanced, i guess the answer would be yes.
Would an lt1 flywheel be fine to put in there with the spec clutch and pressure plate? If those things are neutrally balanced, i guess the answer would be yes.
Thread Starter
Registered User
Joined: Sep 2003
Posts: 627
From: Edmonton, AB, Canada
Re: engine vibration from improper installation of harmonic balancer?
The performance shop replaced the flywheel free of charge, and the vibration is gone. Thanks a lot for guiding me in the right direction!! 
Thread
Thread Starter
Forum
Replies
Last Post
squarehead
General 1967-2002 F-Body Tech
0
Nov 21, 2014 08:02 PM
smokin5s
LT1 Based Engine Tech
5
Jul 24, 2003 10:47 PM
1LEThumper
Forced Induction
40
Jul 14, 2003 12:45 PM
