Piston/Rod question
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 3,252
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From: The Colony Tx
Piston/Rod question
It has been a long time since I rebuilt an engine so I can't remember if the pin is pressed into the piston or the rod. Anyone done this recently that can give me an answer?
For some reason I think the pin is pressed into the piston and the rod should move around the pin to prevent wear to the piston.
For some reason I think the pin is pressed into the piston and the rod should move around the pin to prevent wear to the piston.
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 3,252
Likes: 6
From: The Colony Tx
Originally Posted by Pete K
I think I mis read your question,. If the pin is pressed, it is pressed into the rod end. The piston floats and pivots on the fixed pin.
Race Director
Joined: Feb 2004
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I am not familiar with the term pin slap. I have only heard of piston slap. Piston slap is the piston skirt rocking in the bore. The pin to piston clearance is usually less than .001 of an inch. There is so much oil at this spot that it is unusual to have wear. 1 time I saw the piston pin hole wear out. The owner sprayed a bunch of starting fluid in the motor. It sucked the oil out of the pin area. This caused the pin bore in the piston to oval out.
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Joined: Sep 2000
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From: The Top of Utah
Originally Posted by aj1988
My son is having a problem with his 72 and he pulled the #1 out and the pin moves back and forth in the piston but the rod is tight on the pin.
PISTON slap, is the noise heard when the skirt of the piston "slaps" the cylinder wall. Forged pistons, set up with loose clearances, will "slap" until the engine warms up. Otherwise piston slap is generally associated with pistons that have collapsed skirts.
If a pin makes a noise, it will be a knock. If you have a pin that is knocking, it will be evident with the piston/rod assembly on your hands as when you checked the pin movement.
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