Bought my first C5 and already having problems
Thread Starter
Intermediate
Joined: Jan 2016
Posts: 26
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Bought my first C5 and already having problems
Well yesterday I bought a 99 corvette c5 convertible. The last owner told me that it needs a harmonic balancer I found an OEM replacement for about $80 should I use the OEM or should I get an aftermarket one? Also how hard are they to replace on these cars I am mechanically inclined but I don't want to bite off more than I can chew.
Le Mans Master
Joined: Feb 2012
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From: OK
https://www.corvetteforum.com/forums...nd-damper.html
https://www.corvetteforum.com/forums...r-install.html
https://www.corvetteforum.com/forums...r-install.html
Last edited by 73Corvette; Jan 7, 2016 at 08:37 PM.
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lots of threads on this topic if you do a little searching... I would not use an oem balancer, powerbond or jegs/summit house brand would be a better choice... it would be a perfect time to do a cam but this could start the snowball effect so if you are on a small budget just stick to replacing the balancer, especially if you are doing the work yourself since you won't be paying for labor... also check the front main and cover gasket and replace them if they show any signs of leakage... it isn't a hard job at all in my opinion but you will need a puller and installer which you might be able to rent from a parts store if you don't like buying your own tools
Drifting
Joined: Feb 2008
Posts: 1,596
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From: Bahama North Carolina
It is not a hard job for an experienced mechanic. For someone who is just mechanically inclined you should have experienced help. It will not be an easy job for you. Read up on it. There are several pitfalls you want to avoid and a few specialized tools will be required.
Safety Car
Joined: Dec 2010
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Instructor
Joined: Dec 2013
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From: North Carolina
Same thing happened in my 98'. I went with an ARP Crank Bolt (Reusable 1 time fee of ~35$) and an ATI 10% Underdrive Pulley but I would suggest the 25% underdrive, might as well go full on. I wish I had went to a 25%.
Racer
Joined: Feb 2015
Posts: 299
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From: Chambersburg PA
Thanks
Last edited by DVUSz06; Jan 11, 2016 at 01:08 PM. Reason: spelled a work wrong, didn't want to confirm i as dum as i seam
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Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You have to get the steering rack to a point so the damper is clear and the bolt is accessible. I have never completely removed mine. Just slide it partly out and push the passengers side forward and down.
You will be REMOVING the front cover so you will need:
New damper seal
Ned Front Cover Gasket
While the cover is off, IMHO you should replace the oil pump and timing chain Get a Melling Pump and am LS2/7 Chain.
TOOLS:
You need a damper removal and install tool. DO NOT try to press it back on with the old bolt. You will strip out the crank threads.
You need to find a way to keep the crank pulley from turning.
BC
You will be REMOVING the front cover so you will need:
New damper seal
Ned Front Cover Gasket
While the cover is off, IMHO you should replace the oil pump and timing chain Get a Melling Pump and am LS2/7 Chain.
TOOLS:
You need a damper removal and install tool. DO NOT try to press it back on with the old bolt. You will strip out the crank threads.
You need to find a way to keep the crank pulley from turning.
BC
Instructor
Joined: Dec 2013
Posts: 206
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From: North Carolina
Further research may be needed (and someone please correct me if I'm wrong) but the under drive pulley's reduce the strain that the accessories put on the motor thus increasing power. The smaller pulley spins the accessories slower than the stock causing them to reduce the strain.
I have heard that the 25% UD pulley can give battery recharging problems? But I have never met anyone with that problem so I don't know how much you would have to worry, or if you would have to worry about it at all.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Apparently on these LS1's the crank pulley bolt (harmonic dampener bolt) likes to work it's way inward towards the motor or outward towards the steering rack. Mine worked itself outward toward the steering rack.
Further research may be needed (and someone please correct me if I'm wrong) but the under drive pulley's reduce the strain that the accessories put on the motor thus increasing power. The smaller pulley spins the accessories slower than the stock causing them to reduce the strain.
I have heard that the 25% UD pulley can give battery recharging problems? But I have never met anyone with that problem so I don't know how much you would have to worry, or if you would have to worry about it at all.
Further research may be needed (and someone please correct me if I'm wrong) but the under drive pulley's reduce the strain that the accessories put on the motor thus increasing power. The smaller pulley spins the accessories slower than the stock causing them to reduce the strain.
I have heard that the 25% UD pulley can give battery recharging problems? But I have never met anyone with that problem so I don't know how much you would have to worry, or if you would have to worry about it at all.
QUOTE" "Apparently on these LS1's the crank pulley bolt (harmonic dampener bolt) likes to work it's way inward towards the motor or outward towards the steering rack. Mine worked itself outward toward the steering rack."
Its not the BOLT that does the damage... The damper HUB and the damper OUTER RING are bonded together with rubber. When the rubber bond breaks between the two, the outer ring is what wobbles and or slides forward and or rearward and destroys things.
When the bolt comes loose, the press fit between the damper HUB and the crank fails and the crank starts to spin inside the hub. Eventually the damper either stops driving the accessories or the damper starts wobbling like crazy or both. Remember... C5 dampeners are NOT keyed to the crank. Its just a very tight press fit.
BC
Last edited by Bill Curlee; Jan 11, 2016 at 07:55 PM.