wrist pin clip issues

Charlie Yannetti · 06-12-2017, 12:04 PM

Simple question.. how much vacuum are you pulling??.. too much vacuum will affect oiling to the wrist pins, and possible damage... just an idea..

Wayne Kerr · 06-23-2017, 11:52 AM

Just use a regular one inch travel dial indicator, with an extension. Welding rod for the extension will suffice.

See you at the races,
Wayne Kerr

Adger Smith · 09-08-2017, 10:48 AM

Wayne,
I'm not squirming or pissing and moaning. I agree with you on clearance, but too much makes the pin act like a battering ram on the clips. most applications I deal with .002 to .006 is plenty. But first Get the alky tune up correct where it won't flood when the driver is pedaling it and the pistons and pins won't deflect so much they need more clearance. I do agree pins need end play, but most pistons grow outward at the pin boss when the engine heats up making more pin end play. Flooding it with the alky is probably keeping piston temp down = no piston growth & more deflection of the pin and piston. I have seen the very same thing in Dirt engines with 4" bores. It bothers me to see a driver that has abusive habits. Some times those DT cars have drivers that are real harsh with the loud pedal, too.
There could be multiple issues with this one. It could even be a set of pins that are not up to handling the load the alky puts on them. Pin deflection can be a real serious issue on high cylinder pressure applications. Good luck fixing it.

06-12-2017, 12:04 PM	#1
Charlie Yannetti Senior Member Join Date: Jan 2005 Location: Alpine, NJ Posts: 568 Likes: 188 Liked 192 Times in 83 Posts	Re: wrist pin clip issues Simple question.. how much vacuum are you pulling??.. too much vacuum will affect oiling to the wrist pins, and possible damage... just an idea..

06-23-2017, 11:52 AM	#2
Wayne Kerr Member Join Date: Nov 2003 Location: Out to Lunch Posts: 191 Likes: 2 Liked 26 Times in 11 Posts	Re: wrist pin clip issues Just use a regular one inch travel dial indicator, with an extension. Welding rod for the extension will suffice. See you at the races, Wayne Kerr

09-08-2017, 10:48 AM	#3
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,446 Likes: 575 Liked 880 Times in 311 Posts	Re: wrist pin clip issues Wayne, I'm not squirming or pissing and moaning. I agree with you on clearance, but too much makes the pin act like a battering ram on the clips. most applications I deal with .002 to .006 is plenty. But first Get the alky tune up correct where it won't flood when the driver is pedaling it and the pistons and pins won't deflect so much they need more clearance. I do agree pins need end play, but most pistons grow outward at the pin boss when the engine heats up making more pin end play. Flooding it with the alky is probably keeping piston temp down = no piston growth & more deflection of the pin and piston. I have seen the very same thing in Dirt engines with 4" bores. It bothers me to see a driver that has abusive habits. Some times those DT cars have drivers that are real harsh with the loud pedal, too. There could be multiple issues with this one. It could even be a set of pins that are not up to handling the load the alky puts on them. Pin deflection can be a real serious issue on high cylinder pressure applications. Good luck fixing it. __________________ Adger Smith (Former SS)