piston - cylinder clearance

[Rogggair]

Does anyone know the preferred piston to cylinder clearance for a rebuild?? (gas g-1 - should all b the same)

[Michael Eddie]

Hello roggair, the maximum piston to cylinder wall clearance is .0020 inches (.050mm).

[Rogggair]

Max for rebuilding? So what is the preferred spec? .0012-.0014 is what I heard, but that seems a little small for an air cooled engine... thanx Matti

[Michael Eddie]

Max for rebuilding? So what is the preferred spec? .0012-.0014 is what I heard, but that seems a little small for an air cooled engine... thanx Matti

No that sounds about right. So what did you decide to do.. are you overboreing the engine to a larger piston?

[Rogggair]

yea, just got the piston...had to go .030 over...I've got access to boring & honing equiptment, so it was easy....just looking for the finish hone spec...thanx again

[Michael Eddie]

yea, just got the piston...had to go .030 over...I've got access to boring & honing equiptment, so it was easy....just looking for the finish hone spec...thanx again

Glad to help.. Make sure you have the machinist measure the piston when honing out the cylinder, as opposed to giving him measurements.

[Rogggair]

i am the machinist...

[Michael Eddie]

okay

[Rogggair]

i am the walrus also, but that's a separate issue...

[Michael Eddie]

I'm not even going to question that one