The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support Fuel Injector Clinic
Please Support STM Tuned

Hard to turn wrist pins

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

rpg_dog

10+ Year Contributor
44
0
Sep 20, 2008
Colorado Spring, Colorado
So I spun a rod bearing recently and two of the pistons are somewhat difficult to turn on their wrist pins. They do turn and slide back and forth in the piston, but it requires a fair amount of effort, a good amount more than the other 2. I soaked them in brake cleaner and worked them back and forth for a while, but they don't seem to be getting any easier to turn. I am concerned that bearing material managed to find its way into the wrist pin location. Or am I just being paranoid? Is it okay for the pins to be kind of stiff?? Is there anything I can do to loosen them up? I really want to get my motor back together, but I don't want it to just blow again as soon as I do.
 
Stock pistons and rods have a pressed in wrist pin. Im pretty sure they shouldnt "spin" at all. Its fine that theyre harder to move the piston back and forth. Aftermarket forged internals have a floating pin set up that requires c-clips to hold the pin in its location.
 
They should move freely. The pin is pressed into the rod but there should be .0007-.0009" of clearance between the pin and the pin bore in the piston. The pin could be damaged but the more likely scenario is that the bores in the pistons are distorted. It's not advisable to install them back into the engine this way. Take them all to a machine shop and ask them to press the pistons off and properly size the pin bores in the rods and pistons.
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top