Looking at the video(15:31) I noticed an error on the cylinder. it's too tall. That cylinder needs to be machined on the top . I have done it multiple times. Plus those cylinder heads have a big combustion chamber.
Got a 2003 polaris sportsman 90 checked compression and im not getting anything on the gauge is that normal, to not get anything zero, zip, nada! Looks like the engine over heated bad the plastic cover on the head was melted!
@insanitycarnival27 tester was working...removed top end and the piston was severely damaged..the rings were welded shut in the groves and piston pretty badly scored. I'm getting ready to replace it thanks alot for this video! Wish me luck...I hope this is the only issue!
@insanitycarnival27 Success its getting 70lb of compression, and it starts with a wet gasoline rag. Because the carburetor is not working, I cleaned it three times already not getting fuel! Ordered a new carburetor! Hopefully, that gets it running to where the kids can use it during their Christmas break!
What's compression suppose to be ? Just got one of these an mine is at 60 psi. It runs when u put your hand over the carb an choke it. Not wanting to pull fuel through carb. After u fixed the bad crank seal did compression go up ? If so what to?
@@insanitycarnival27 Gewd. You're like a one man band. Thanks for the help by the way. My son and I are doing a 100cc bore rebuild on his little 90cc this weekend.
Looking at the video(15:31) I noticed an error on the cylinder. it's too tall. That cylinder needs to be machined on the top . I have done it multiple times. Plus those cylinder heads have a big combustion chamber.
Thank you for passing this along!!
great video!
Got a 2003 polaris sportsman 90 checked compression and im not getting anything on the gauge is that normal, to not get anything zero, zip, nada! Looks like the engine over heated bad the plastic cover on the head was melted!
That is weird. Is your compression tester working? Test it on another engine to see the results.
@insanitycarnival27 tester was working...removed top end and the piston was severely damaged..the rings were welded shut in the groves and piston pretty badly scored. I'm getting ready to replace it thanks alot for this video! Wish me luck...I hope this is the only issue!
@@lgvmobile Good Luck! Hopefully it goes smoothly! Check that the crank moves freely once yo have the piston out of the cylinder head.
@insanitycarnival27 Success its getting 70lb of compression, and it starts with a wet gasoline rag. Because the carburetor is not working, I cleaned it three times already not getting fuel! Ordered a new carburetor! Hopefully, that gets it running to where the kids can use it during their Christmas break!
@@lgvmobile great job!!!
Very helpful thank you
Will this fit 90 ds suski?
Is there a difference in the top and bottom ring?
No there the same size
You made that look super easy hope it goes like that for me👍 On the compression why was it only 75 ?
Bad crank seal is the reason for low compression. Needs to be replaced.
What's compression suppose to be ? Just got one of these an mine is at 60 psi. It runs when u put your hand over the carb an choke it. Not wanting to pull fuel through carb. After u fixed the bad crank seal did compression go up ? If so what to?
Low compression can be caused by valves leaking You can take the valve cover off and take a flashlight shine thru if you see lite then it’s leaking
@@whowho7969 it's a 2 stroke no valves
Ya why 75psi
Bad crank seal is the reason for low compression. Needs to be replaced.
Do you listen to tenacious d?
Of course
@@insanitycarnival27 Gewd. You're like a one man band. Thanks for the help by the way. My son and I are doing a 100cc bore rebuild on his little 90cc this weekend.