Kohler Cv20 problem

[Cs111]

Hi guys. First post here 
I bought an old ( I think 1998 ) craftsman lawn tractor with a kohler Cv20s engine to do up for the kids. Wasn't starting and been neglected .
New starter brushes and solenoid, fuel filter and I eventually got it running with a few exhaust bangs etc.  
now to the engine problem !
It's starting and running fine however there is quite a lot of spitting oil and air rushing up through the dipstick pipe. I changed the oil and filter and the old oil is like a cup of brown / grey coffee. I took the air filter of and it's not sucking in air 
many ideas what I should be looking at?

[openspaceman]

1 hour ago, Cs111 said:

I should be looking at?

new piston rings perhaps

[adw]

Check the engine breather, if your getting pressure in the crankcase I’d could be faulty, if not Worn cylinder, piston and rings

[Cs111]

Had a better chance to check a few things. 
Both plugs were pretty black when removed, not caked, but black.

compression on both sides sitting at 90psi

i added 5ml of oil to each cylinder and got the same readings give or take a couple of psi.

It will only start with the choke hot or cold, but I can turn the choke off after 2 seconds when the engine is hot and it runs ok. 
starting no problem but just not running as it should. 
dipstick is milky white after fresh oil 

 

Edited January 21, 2022 by Cs111