I need harmonic help!
Thread Starter
4th Gear
Joined: Oct 2010
Posts: 4
Likes: 0
I need harmonic help!
My buddy has a 84 vette with crossfire injection.
recently the rubber in the harmonic balancer blew out so he had the typical noise. Well we bought the new balancer with just one problem....we cant get the old one off. weve tried using the ducks foot puller but no success, the hub just wants to keep spinning, any tips
? ive heard there is a positioning screw thats an allen key but not sure, any diagrams or anything someone could show me to help me out with? thanks
recently the rubber in the harmonic balancer blew out so he had the typical noise. Well we bought the new balancer with just one problem....we cant get the old one off. weve tried using the ducks foot puller but no success, the hub just wants to keep spinning, any tips
? ive heard there is a positioning screw thats an allen key but not sure, any diagrams or anything someone could show me to help me out with? thanks
Race Director
Joined: Jun 1999
Posts: 14,924
Likes: 9
From: Merritt Ils Fl
The puller you describe should be pulling straight out. The crank turning shouldn't make any difference. The balancer hub is keyed to the crank and should not rotate unless the crank rotates.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
You are supposed to block off the flywheel. I think they may make a tool for this.
Or you can do what alot do and put a vice grip on the flywheel. Just try and put it to where the vice grip doesn't make contact with something you don't want it to on the block.
Or you can do what alot do and put a vice grip on the flywheel. Just try and put it to where the vice grip doesn't make contact with something you don't want it to on the block.
Drifting
Joined: Aug 2006
Posts: 1,624
Likes: 2
From: Canandaigua New York
It's a long rectangular piece of metal in the slot of the harmonic balancer and crankshaft. The keyway 'locks' it in place on the crankshaft and aligns the balancer so it sits in the proper position.
You need a puller to remove the balancer.
<----- keyway in slot on crankshaft
Last edited by Keystring; Oct 6, 2010 at 05:24 PM.
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Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
Make sure you put some high temp RTV in the keyway on the new balancer right before you press it back on. If you don't, oil can work its way up the keyway slot and sling all over the engine bay.
You'll also want to put blue thread lock on the crank/balancer bolt and pulley bolts. And it is a good idea to use a torque wrench to torque them to spec.
Something I pulled from the net to give you the idea:
14. Clean off the old gasket sealant from the crank snout key. Be careful not to use any sharp objects or risk tearing into the oil seal (this will be a bad thing). I laid down a thin layer of Mobil 1 grease on the face of the oil seal as well as the crank snout (but not in the area of the key way).
17. I laid down a good bead of RTV into the key way of the pulley. You only have a few minutes before the RTV starts to harden up, so be prepared to install it right away.
You'll also want to put blue thread lock on the crank/balancer bolt and pulley bolts. And it is a good idea to use a torque wrench to torque them to spec.
Something I pulled from the net to give you the idea:
14. Clean off the old gasket sealant from the crank snout key. Be careful not to use any sharp objects or risk tearing into the oil seal (this will be a bad thing). I laid down a thin layer of Mobil 1 grease on the face of the oil seal as well as the crank snout (but not in the area of the key way).
17. I laid down a good bead of RTV into the key way of the pulley. You only have a few minutes before the RTV starts to harden up, so be prepared to install it right away.
Burning Brakes
Joined: Oct 2009
Posts: 773
Likes: 2
From: Minneapolis MN
[QUOTE=joshwilson3;1575543156]Make sure you put some high temp RTV in the keyway on the new balancer right before you press it back on. If you don't, oil can work its way up the keyway slot and sling all over the engine bay.
Why put silicone on the key/keyway when the oil seal,seals the oil from leaking out the front seal not siliconing the keyway?I never heard or seen this.What does siliconing the keyway do?If the front seal starts leaking siliconing the keyway will not do anything.I know you should silicone the center balancer bolt but explain why the keyway?
Why put silicone on the key/keyway when the oil seal,seals the oil from leaking out the front seal not siliconing the keyway?I never heard or seen this.What does siliconing the keyway do?If the front seal starts leaking siliconing the keyway will not do anything.I know you should silicone the center balancer bolt but explain why the keyway?
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
Why put silicone on the key/keyway when the oil seal,seals the oil from leaking out the front seal not siliconing the keyway?I never heard or seen this.What does siliconing the keyway do?If the front seal starts leaking siliconing the keyway will not do anything.I know you should silicone the center balancer bolt but explain why the keyway?
The keyway leaking oil doesn't have anything to do with the timing cover seal. I believe even dealers have RTV'd this keyway to fix this kind of leak. It is just something that may or may not leak. Sure would suck to find out after putting it all back together.
On another GM car with a V8. I replaced the harmonic balancer. Months later I noticed oil was slinging from the crank pulley. I checked around and found out about sealing the keyway. As the keyway would be the only way oil could have been getting to the crank pulley to then be slung. So I pulled the balancer, cleaned up the oil. RTV'd the keyway slot in the balancer with black high temp RTV. And that fixed the leak.
On the center balancer bolt. I didn't seal that. I just put blue thread lock on it as well as the crank pulley bolts.
Burning Brakes
Joined: Oct 2009
Posts: 773
Likes: 2
From: Minneapolis MN
Oil can work its way past the keyway and sling on the engine bay. The keyway isn't necessarily a press fit like the smooth part of the balancer.
The keyway leaking oil doesn't have anything to do with the timing cover seal. I believe even dealers have RTV'd this keyway to fix this kind of leak. It is just something that may or may not leak. Sure would suck to find out after putting it all back together.
On another GM car with a V8. I replaced the harmonic balancer. Months later I noticed oil was slinging from the crank pulley. I checked around and found out about sealing the keyway. As the keyway would be the only way oil could have been getting to the crank pulley to then be slung. So I pulled the balancer, cleaned up the oil. RTV'd the keyway slot in the balancer with black high temp RTV. And that fixed the leak.
On the center balancer bolt. I didn't seal that. I just put blue thread lock on it as well as the crank pulley bolts.
The keyway leaking oil doesn't have anything to do with the timing cover seal. I believe even dealers have RTV'd this keyway to fix this kind of leak. It is just something that may or may not leak. Sure would suck to find out after putting it all back together.
On another GM car with a V8. I replaced the harmonic balancer. Months later I noticed oil was slinging from the crank pulley. I checked around and found out about sealing the keyway. As the keyway would be the only way oil could have been getting to the crank pulley to then be slung. So I pulled the balancer, cleaned up the oil. RTV'd the keyway slot in the balancer with black high temp RTV. And that fixed the leak.
On the center balancer bolt. I didn't seal that. I just put blue thread lock on it as well as the crank pulley bolts.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
Where did the oil come from?Is there a oil passage in the keyway?For oil to make it to the key way,the front seal or seals,or another leak has to be getting oil to the keyway.Oil will sling around regardless if the keyway is siliconed or not as oil getting on harmonic balancer or on crank in general will get thrown from centrifical force.Oil getting to keyway wouldn't matter compared to oil getting inbetween the crank & balancer on the Lt1 because its a press-fit without a keyway & could cause the balancer to spin on the crank,thus damaging crank & balancer.Again I ask,where does the oil come from to get into keyway?
The oil comes from the engine. The keyway is exposed to engine oil. The keyway isn't a press fit, so it isn't perfect. Like I said. The keyway leaking oil and the timing cover seal have nothing to do with each other.
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Are you using the correct puller?
A harmonic balancer puller looks like the letter Y and bolts to the 3 front hole that the crank pulley bolts occupy.
This type of puller has a threaded rod that goes through the center, and pushes off the crank snout. It has a rollerized bearing on the tip of the threaded rod to prevent what you are experiencing.
Use the right puller, if you are not doing so currently. If you are using the correct puller, you will have to lock the flexplate by carefully placing a long screwdriver between it, and the block.
A harmonic balancer puller looks like the letter Y and bolts to the 3 front hole that the crank pulley bolts occupy.
This type of puller has a threaded rod that goes through the center, and pushes off the crank snout. It has a rollerized bearing on the tip of the threaded rod to prevent what you are experiencing.
Use the right puller, if you are not doing so currently. If you are using the correct puller, you will have to lock the flexplate by carefully placing a long screwdriver between it, and the block.
Drifting
Joined: Aug 2006
Posts: 1,624
Likes: 2
From: Canandaigua New York
Are you using the correct puller?
A harmonic balancer puller looks like the letter Y and bolts to the 3 front hole that the crank pulley bolts occupy.
This type of puller has a threaded rod that goes through the center, and pushes off the crank snout. It has a rollerized bearing on the tip of the threaded rod to prevent what you are experiencing.
Use the right puller, if you are not doing so currently. If you are using the correct puller, you will have to lock the flexplate by carefully placing a long screwdriver between it, and the block.
A harmonic balancer puller looks like the letter Y and bolts to the 3 front hole that the crank pulley bolts occupy.
This type of puller has a threaded rod that goes through the center, and pushes off the crank snout. It has a rollerized bearing on the tip of the threaded rod to prevent what you are experiencing.
Use the right puller, if you are not doing so currently. If you are using the correct puller, you will have to lock the flexplate by carefully placing a long screwdriver between it, and the block.
One of these ...
