718,, vanguard to a 630 honda swap

[F Mcgonnygo]

my 718 grasshopper 18hp is pushing oil out the vent tube. It has 150lbs compression on both side. I replaced both head gaskets, changed the oil n filter and oil level is under the full line. Starts n runs but loses power as filter gets dirty. It was just a mist out the tube,, thats when I put new head gaskets on and now its worse. I figure it's got a crack so i've saw some 718 grasshoppers with a 630 honda on them. Anyone done one? Any ideas are appreciated? Or any ideas on the old vanguard problem?

 

[mechanic mark]

I'd be looking at Big Block Vanguards.