Subaru Enthusiasts Car Club of the Sierras - View Single Post - Okay, now what? (sperry's motor tear-down thread)

MPREZIV · 2007-08-20, 06:24 AM

Jeremy came over last night, and we were talking a bit about your motor Scott. After telling him what we found, he informed me that the piston pins in the turbo 2.5l are offset by about 2mm, which causes the piston to actually rock side to side in the cylinder when traveling up and down. All pistons do this to a degree, but the STi setup causes it to be more pronounced. Perfectly normal. In fact, it seems that if you were to pull a head and NOT see that top and bottom scoring that we found, you've likely got a frozen piston pin. So if nothing else, it seems that there's no worry with those cylinder marks. Good news I suppose.

2007-08-20, 06:24 AM	#58
MPREZIV Token Real Name: Le Stig Afrique? Join Date: Jun 2005 Location: sitting next to a big yellow box Posts: 3,589 Car: 2001 Impreza 2.5 RS Class: 05 TDSP No, I won't work on your car. F your car*	Jeremy came over last night, and we were talking a bit about your motor Scott. After telling him what we found, he informed me that the piston pins in the turbo 2.5l are offset by about 2mm, which causes the piston to actually rock side to side in the cylinder when traveling up and down. All pistons do this to a degree, but the STi setup causes it to be more pronounced. Perfectly normal. In fact, it seems that if you were to pull a head and NOT see that top and bottom scoring that we found, you've likely got a frozen piston pin. So if nothing else, it seems that there's no worry with those cylinder marks. Good news I suppose. __________________ "...these condoms have a topical anesthetic to reduce sensitivity, so you can last longer. What a paradox. You can't feel a thing, but you can f*ck for HOURS..."