Not sure where to post this...Anyway, my snowcat has an old 1972 Ford 98 CID/1.6Liter/four cylinder industrial engine (Pinto basically). Starts great, runs great until warm. Then has a very rough idle to the point of near stalling. Once the RPM's are a bit higher it runs fine with good power, etc. Vacuum leak? Any tips? Thanks in advance.

 

It's not a Pinto, it's a Kent, and it may have
carb troubles, idle circuit may be kinda lean too
little fuel, check the idle mixture screw is about
2 or so turns out from gently all the way in when
hot.

 

Probable a gummed up idle circuit.