Yamaha 90 hp 2 stroke

[maineiac5586]

I acquired a 2003 90 hp 3 cylinder with oil injection. Top 2 cylinders 120 psi bottom 50 psi. Bottom carb overflows when running engine I assume because not enough compression to pull in the mixture or the float is stuck. Not sure what the condition was when the bottom cylinder went bad. Hoping it was a head gasket I pulled the head and found the scuffs in the cyinder wall. The scuffs on the lower side of the cylinder I can't feel with my finger but the ones on the top of that bore I can. Also the combustion area of the head was clean compared to the 2 good cylinders. I don't see any breaks in the gasket. Not sure what caused this? Can those scuffs in the bottom bore be enough to cause such a drop in compression? Where to go from here? Thanks

 

[maineiac5586]

Picture of head gasket

 

[99yam40]

bottom carb is usually the one that collects a lot of junk for some reason.
if that cylinder leaned out it will get too hot and score the cylinder walls.
boring and installing an oversized piston would be needed.
or boring all 3

 

[racerone]

Time to take it apart for inspection.-----Used parts might be available.-----Your location ?

 

[maineiac5586]

Time to take it apart for inspection.-----Used parts might be available.-----Your location ?

Lawrenceville nj