OPmini
moo
Hello all! I recently noticed that my predator 420 lost some compression and started burning oil (due to dust getting in the engine, where I ride in the desert the dirt is as fine if not finer than baby powder and I previously didn't have an oiled air filter), so I changed all the rings out for new OEM ones and put it back together. It worked fine for a few hours but then I noticed extremely low compression when cold starting the engine and some smoke when accelerating, so I pulled the dipstick and sure enough the oil smells like exhaust (I use Pennzoil platinum synthetic 10w-30). The head gasket looks good to me. I also checked the valve seals they look fine to me (also shouldn't there be valve seals on both valves???). In one of the pictures below I have my finger pointing at the cylinder wall, where I'm pointing I can feel a very small lip is that normal? (The lip isn't anything extreme I can't see it but can feel it, just barely) I also did the 'oil through sparkplug hole' test and there was no compression gain pointing to valve seals being the issue, as well as mostly seeing smoke when accelerating or idling. But that would not explain the lower compression or exhaust smell in the oil. Does anyone have ANY ideas on what is wrong? Thanks in advance!
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