Replacing Harmonic Balancer in the car
Thread Starter
Race Director
Joined: Jul 2004
Posts: 12,706
Likes: 329
From: Scottsdale Arizona
Replacing Harmonic Balancer in the car
I've posted a couple of times before that my balancer had sppun. Well this weekend I followed Lars' paper on finding TDC (thanks Lars 
) and marked the balancer (liquid paper; works like a charm).
When I started to time the engine, it became apparent that the mark was wandering.
Bottom line is that I need to change the balacer. I stared at it log enough to decide that it wasn't going to be much fun. I thought that I'd just get enough clearance if I remove the fan and pullies. Has anyone done this change without removing the engine, rad, front end...? I'm slightly concerned that I'll start the job, find out that I can't reach what I need to, lose my temper and get out the reciprocating saw.
) and marked the balancer (liquid paper; works like a charm).When I started to time the engine, it became apparent that the mark was wandering.
Bottom line is that I need to change the balacer. I stared at it log enough to decide that it wasn't going to be much fun. I thought that I'd just get enough clearance if I remove the fan and pullies. Has anyone done this change without removing the engine, rad, front end...? I'm slightly concerned that I'll start the job, find out that I can't reach what I need to, lose my temper and get out the reciprocating saw.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Originally Posted by CA-Legal-Vette
I've posted a couple of times before that my balancer had sppun. Well this weekend I followed Lars' paper on finding TDC (thanks Lars ) and marked the balancer (liquid paper; works like a charm).
When I started to time the engine, it became apparent that the mark was wandering.
Bottom line is that I need to change the balacer. I stared at it log enough to decide that it wasn't going to be much fun. I thought that I'd just get enough clearance if I remove the fan and pullies. Has anyone done this change without removing the engine, rad, front end...? I'm slightly concerned that I'll start the job, find out that I can't reach what I need to, lose my temper and get out the reciprocating saw.
) and marked the balancer (liquid paper; works like a charm).When I started to time the engine, it became apparent that the mark was wandering.
Bottom line is that I need to change the balacer. I stared at it log enough to decide that it wasn't going to be much fun. I thought that I'd just get enough clearance if I remove the fan and pullies. Has anyone done this change without removing the engine, rad, front end...? I'm slightly concerned that I'll start the job, find out that I can't reach what I need to, lose my temper and get out the reciprocating saw.
Are you SURE you need to change the balancer? When they slip, the timing does NOT "wander" - it moves (rotates) to the wrong place.
"Wandering" timing mark is usually a sign of distributor shaft and/or bushing slop.
If you do change the balancer, buy a decent remover/installer tool or you can cause much bigger problems. If you don't get it on correctly and use excessive force or banging, you could end up buying a new crank, also.
Race Director
Joined: Oct 2002
Posts: 12,065
Likes: 2
From: Smalltownville Michigan
Cruise-In 5, 6 & 10 Veteran
St. Jude Donor '09
the balancer isnt that bad.. just be patient.. the threads on the puller are pretty long winded.. and go ahead and plunk out the money or even rent the installation tool.. makes it a lot less painful going back on!
Melting Slicks
Joined: Aug 2003
Posts: 2,135
Likes: 2
From: Dayton Oh
replacing is not a big problem but use a puller and balancer installation tool. ONE STRONG WORD OF ADVISE: Check the new balancer on your bench to ensure the bolts holes have been correctly tapped and that the timing mark & crank notch aligns per stock. Ask me what happens if you don't bench check this stuff and install just to find out nothing is aligned as it should be and the bolts will not fit allowing you to take the piece of excriment back off. 
Le Mans Master
Joined: Apr 2001
Posts: 5,941
Likes: 281
From: Was New Orleans but swam to Baton Rouge LA
Cruise-In IX Veteran
A balancer change is easy. I have done it recently on my 71. I have electric fans now which make it easier, but when I did it with the clutch setup it was not that bad. Remove the fan shroud and fan. After that loosen the alternator and PS if you have it and remove the belts. Next I removed the pull from the balancer and finally started pulling the balancer with a puller. The puller can be had from autozone for under 30 dollars I believe. I suggest a big wrench or a piece of pipe to help turn the wrench. The balancer is normally on there good and you need some leverage. Installing the balancer is a little harder, but what I have done is got a few other bolts that are longer the the stock one. I used these bolts with washers and a socket to slowly install the new balancer appling even pressure. Do not use a hammer as you may damage something.
Race Director
Joined: Jul 2002
Posts: 11,593
Likes: 173
From: Clayton NC
This has been a good thread I was under the impression that it could not be done with the motor in the car. Just for the fact it's so tight down there... Thanks guys for the info... Dave..
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Takes me about 20 minutes to replace the balancer with the balancer install/removal tool... I would not recommend doing the job without that tool...
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Thread Starter
Race Director
Joined: Jul 2004
Posts: 12,706
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From: Scottsdale Arizona
Just to update all of you, I went ahead nd finished this last night. It was possible to do without removing the engine or rad, but Big G was right. It took a fair bit of patients and was fiddly rather than hard. I also found a number of interesting items.
First of all, this car has always had a severe belt whine that I could never solve. Turns out that the power steering pully had a 1/4 inch or larger bend in it. Hopefully changing that will make the whine go away.
Second, the harmonic damper was in TERRIBLE shape. Not only had it spun, but the outer ring had pushed back on the inner ring about 3/8 of an inch. I always wondererd why it was so hard to see the timing mark. Turns out it was because most of it was under the indicator.
My last task is replacing it with a new one. I do have one last question though. Will I have to do anything special to make sure that the key aligns with the new damper or will it index on its own if I push it on a little and spin it?
Thaks for all your help, as always.
First of all, this car has always had a severe belt whine that I could never solve. Turns out that the power steering pully had a 1/4 inch or larger bend in it. Hopefully changing that will make the whine go away.
Second, the harmonic damper was in TERRIBLE shape. Not only had it spun, but the outer ring had pushed back on the inner ring about 3/8 of an inch. I always wondererd why it was so hard to see the timing mark. Turns out it was because most of it was under the indicator.
My last task is replacing it with a new one. I do have one last question though. Will I have to do anything special to make sure that the key aligns with the new damper or will it index on its own if I push it on a little and spin it?
Thaks for all your help, as always.
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
I use a balancer removal/install tool.. Takes about 15 minutes to replace the balancer with that tool... Very easy and straight forward..
Thread Starter
Race Director
Joined: Jul 2004
Posts: 12,706
Likes: 329
From: Scottsdale Arizona
Originally Posted by GrandSportC3
I use a balancer removal/install tool.. Takes about 15 minutes to replace the balancer with that tool... Very easy and straight forward..
It took a surprising amount of force to remove the old damper even with the correct puller.
Melting Slicks
Joined: May 2003
Posts: 2,253
Likes: 1
From: Rochester Kent
Originally Posted by GrandSportC3
Takes me about 20 minutes to replace the balancer with the balancer install/removal tool... I would not recommend doing the job without that tool...
That tool is invaluable, wouldnt want to do it either without it 
