I have had this ski for a year and had non-stop problems with hard starting. Discovered that the muffler mounting points are broken and stripped so ordered a used replacement, but did a compression test last night and found 125 psi in the front and 145 psi in the rear. The cylinder wash looks good on both with black/wet domes and clean areas by the ports. I added a little WD40 to the front cylinder but the compression did not change. Now I can't get it started at all...it will start to fire if I inject carb cleaner directly into the cylinders, but won't stay running. It ran well when I took it out this last weekend. Any ideas on the compression and starting issue.

I want to sell this ski (kids want something faster) but don't want to dump a lemon on someone.