kens clidlesdales

Thanks lynnmor for your advise. we will check the compression and go from there but my guess is that the engine has to come apart.

Thanks much I'll check that next

Would you know what the compression should be?

I was thinking compression as well. Is there normally pressure in the crank case?

Hello there all you fellow wheel horse owners. I have 3 my self. 520-H, 418-A and the one I've own since 1994 the 312-8 .The 520 and the 418 I am restoring. I am having A problem with the 520 I mowed with it for the first time this week and it fouled a plug pulled the air cleaned off and there was oil on the inside of the air cleaner so I replaced the spring in the valve cover that holds the reed valve in place and the filter but the problem is still there. it seems that the crank case is under pressure. Do you have any idea what could be the problem? thanks