I have a 2005 Arctic cat 650 V2. Here is the story, It is actually me father-n-laws wheeler and last year he rolled it pretty bad. It ran after words but he said it was running really lean and backfiring. Later they discovered the rear carb boot was partially off. So i tore down the engine and the rear piston was melted down and the rings were pinched into the grooves and would not move. I replaced the piston and rings and new seals I also timed it according to the manual. By the way, when i started working on this machine it did not run. He said it just wouldnt start one day. Anyway, the issue now is it still wont start. It has spark and fuel but it will not start. I tried a little starting fluid and no change. Once in awhile i will get a backfire through the rear carb. I dont know where to go from here.

 

What is the compression at, does it meet the minimum spec?

 

It is lower than spec but it says to do it Properly the engine must be warm. So i thought that might be a reason for it to be low. I sprayed some ether in the spark plug hole and it still wont fire. It seems like timing but i did the rear cyl according to the manual. I find it hard to beleive both cyclinders were out of time but im gonna check the front tonight. It is only backfiring out the rear carb though.

 

So I did another compression test on it last night and it had zero compression on the rear cylinder still. I tore the engine down to the piston again and discovered that i had put the top two rings on in the wrong order. Would this cause it to have no compression at all? Also if anyone knows, I am worried that the head gasket is not going to seal correctly because it is just a peice of tin. Should i put any gasket maker on this or just put it in by itself?