Head clearance

[NAMBA860]

Looking for help on a K/B drum rotor 3.5 inboard. I’m running 50% what should the head clearance be and what’s the best way to measure it?

 

[dave roach]

Set the head clearance at .006

Dave

 

[Kristy Wallace]

Set the head clearance at .006

Dave

That's pushing it on the old gal.

0.010" be safe

 

[Kristy Wallace]

Just use some small soft solder cut a piece the dia of the bore,and place it center across the piston /piston pin.
Or use a dial and zero out with the button on a flat even surface,get zero then replace button in engine and hand turn over engine with dial connected to button..

 

[Timbo Whalen]

Set the head clearance at .006

Dave

That stock K&B rod will not handle that, for long..... .009" on 50% is pushing it.... like Kristy said, .010" on 50%, and run it....stay on fat side of needle with a cold plug.

Personally, I like a depth micrometer, and also used shims that have been compressed, if in otherwise good shape....have yet to poof ANY engine.

 

[Dave Gilles]

I set my outboard somewhere around .008" with 50%. like doubled the power. first time I ran it was a half turn lean and the tunnel hull literally shot itself 4' into the air.