69 427
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Safety Car
Joined: Apr 2006
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From: BC
69 427
I finally got the motor out. It turned out to be a ball bearing that punched a hole in number two piston. Where the hell does an eighth inch ball bearing come from...
I have the block and crank over at the machine shop. Cross drill the crank and have a set of Kieth Black forged pistons for it. The guy at the machine shop said, if you want to do this right, we should balance the clutch to the motor. I had never thought of that. Anyway, going with high end internals, a Comp near stock roller cam and still trying to figure out where the ball bearing came from. Check the hole... The top one is not supposed to be there and neither are the two indentations just above it.... That is a 45 year old from the factory motor and I really did not want to be the one to take it apart.
I have the block and crank over at the machine shop. Cross drill the crank and have a set of Kieth Black forged pistons for it. The guy at the machine shop said, if you want to do this right, we should balance the clutch to the motor. I had never thought of that. Anyway, going with high end internals, a Comp near stock roller cam and still trying to figure out where the ball bearing came from. Check the hole... The top one is not supposed to be there and neither are the two indentations just above it.... That is a 45 year old from the factory motor and I really did not want to be the one to take it apart.
Last edited by CanadaGrant; Apr 28, 2015 at 02:37 PM.
Le Mans Master
Joined: Jan 2006
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From: Butler Pa
I have the block and crank over at the machine shop. Cross drill the crank and have a set of Kieth Black forged pistons for it. The guy at the machine shop said, if you want to do this right, we should balance the clutch to the motor. I had never thought of that.
Le Mans Master
Joined: Jan 2006
Posts: 6,505
Likes: 139
From: Butler Pa
To do it right, the clutch and pressure plate assembly should have a neutral balance. That way it can be replaced with another one with a neutral balance without affecting the engine balance.
If a machine shop told me they wanted to balance the engine with the clutch on it, I'd pull everything out of there and go to a different shop.
Thread Starter
Safety Car
Joined: Apr 2006
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From: BC
The internals will be balanced but I had never thought of looking at the clutch. It didnt even occur to me. Then the machine shop owner is talking about balancing, make everything smooth and Im thinking, all this work then bolt up a flywheel, clutch and pressure plate that isnt even close... Why balance something if you are going to throw it off.
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
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From: BC
If a machine shop told me they wanted to balance the engine with the clutch on it, I'd pull everything out of there and go to a different shop.
They told me they would like to balance the engine but figured it was important to have the flywheel, clutch, and bolts in order after they had done the crank, rods, pistons. I kind of like it. I used to own a shop that turned crankshafts and built race motors but never thought about the clutch assembly throwing off my work.
They told me they would like to balance the engine but figured it was important to have the flywheel, clutch, and bolts in order after they had done the crank, rods, pistons. I kind of like it. I used to own a shop that turned crankshafts and built race motors but never thought about the clutch assembly throwing off my work.
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Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
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From: BC
The clutch assembly won't throw anything off if it has a neutral balance.
Well, I just pulled a clutch from Corvette Central and what you say is bs. Neutral balance is just a dream. You assume it has neutral balance but doesnt wash.
Well, I just pulled a clutch from Corvette Central and what you say is bs. Neutral balance is just a dream. You assume it has neutral balance but doesnt wash.
Le Mans Master
Joined: Jan 2006
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From: Butler Pa
I'll ask again, what happens if you need to replace the clutch? Do you then need to rebalance the engine?
Drifting
Joined: Sep 2010
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From: Laguna Niguel California
Normally the flywheel, clutch and disk are balanced as a unit independent from the engine internals. Only externally balanced engines like the 454 and 400 require an externally balanced flywheel. If you are buying a clutch separately, yes it will have to be balanced, but as a set with the clutch disk and flywheel.
Drifting
Joined: Sep 2010
Posts: 1,412
Likes: 50
From: Laguna Niguel California
Almost forgot, the hole in the piston is a lightening hole.
Well if you don't believe that, it could be a ball check from the carburetor. If you had some rough running that could be the reason.
Well if you don't believe that, it could be a ball check from the carburetor. If you had some rough running that could be the reason.
Safety Car
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From: Austin Texas
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you balance the flywheel with the rotating engine assy... always,
not the clutch assy.
you buy a balanced clutch assemble that should be balanced from the clutch manufacturer.
not the clutch assy.
you buy a balanced clutch assemble that should be balanced from the clutch manufacturer.
Last edited by 69Vett; Apr 28, 2015 at 04:35 PM.
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
The engine will be balanced but I had never thought about the clutch. We all pay attention to the little things then forget about the other things. I checked the original clutch and it has four drill or balance marks in it so it was actually balanced at the factory. Will try and get a pic.
Ok. See the drill holes? I would balance the motor but had never thought about doing the clutch and would never think about doing it on the engine.
Last edited by CanadaGrant; Apr 29, 2015 at 05:35 PM.