Thread: Low compression
View Single Post
Old 02-27-2011
westman995's Info
Join Date: Jan 2008
Location: Minnesota
Posts: 3,675
Default Low compression

Ok so i put together my friends motor for him that he blew up. The new parts that were put on it were two new SPI pistons, one cylinder, crank seals, and all new gaskets.

Well, it has low compression. It only has like 90-100 psi at the very most. It runs, it has power SOMETIMES.. I feel as if it shouldnt even run as decent as it does with only around 90 psi per cylinder.

Now im wondering, why in the hell would it have low compression on brand new pistons and rings? One of the jugs is the same one that was on it when it blew up and it had over 120 psi or something like that before.

Is it possible that the rings were put on upside down There are two rings per piston. And i checked over the instructions, nothing about which way the rings went on. They rings were squared all around, none of the edges were rounded or anything.. The SPI pistons and rings i put on my 700 polaris had to be put on a certain way and were rounded off of whatever on one edge of the ring. I didnt see any way i could have put these rings on the wrong way since they are square all the way around?? Hmm..
Reply With Quote