Noticeable loss of power after removing piston head from block


New Member
Sep 26, 2019
Out of curiosity, I took the head and sidewall of the engine block off to see what it's like down there. When I put it back together, I noticed some power loss especially at the low end. When I was putting the piston head into the middle chunk of iron (where carburetor and exhaust attaches to), I did have a hard time fitting the rings into the hole. Some characteristics i noticed is that the cylinder head is all black and there are minor scratches on the sidewall. Did I mess up somewhere and caused permanent damage to the engine?

kelly dean

Active Member
Oct 3, 2019
a lot of things can go wrong installing the cylinder. sliding the cylinder down over an installed piston is difficult and not the way i do it but everybody will have their own way. rings are a very brittle material and easy to break. the ring grove on the piston has tiny pins where the ends of the rings have to line up as far as damage pics would have helped, but the first thing to address is the head gasket the stock aluminum gasket is pretty much a one shot thing a head leak will mean lots of power loss. assuming no serious damage or really bad scars in the cylinder the fist thind to do is get a good copper head gasket....kelly


Well-Known Member
May 1, 2011
Newnan,Georgia U.S.A.
One thing you can try is sanding the head to make sure it is flat, I tape 400 grit sand paper to a known flat surface and sand the head in a circular motion. I do this to every head if I remove it, be sure to torque the nuts also, 12 foot pounds is good. Don’t over tighten or you can warp the head.