8 N compression test now what?

1st- Knocking from #4cycl.
2nd- oil on plug from # 3 cycl.
3rd- losing power when hoggin also started backfiring some, starts good,idles good but under a load tries to quit it does this going up a small grade whether cutting or not.

Did a compression check.
Results: DRY #1 90 psi Wet #1 90 psi #2 100 psi #2 110 psi #4 89 psi #4 110 psi #3 100 psi #3 110 psi A little black smoke or burnt place on head just above the manifold.

What do ya think guys?

Your knock could well be a hole in the exhaust gasket.

But this doesn't address your "weak engine" problem. A tune-up would be a good place to start. The governor should respond to the load of going up a hill, it sounds like it doesn't. Do the I&T FO-4 governor adjust proceedure.

The backfiring sounds like poor ignition timing, or bad centrifical advance. Lack of power and backfiring is a timing issue. Check your centrifical advance weight mechanisms per your I&T FO-4 proceedures.

Bottom line, I think you have a good engine, donna mucka round, just fix the ignition and governor..... ..Dell