Unfortunately that was exactly how I tuned the engine.

I used a standard prop in a test stand and set it up as I normally would.

I ran several tank fulls through the engine without any problems or hesitation.

I was running the engine slightly rich for a tractor since it was still fairly new... but it seemed fine.



When I installed it on by Bobcat with a pusher prop, the engine siezed after running it for less than a minute.

At first I thought something was wrong with the engine and I took it home & pulled off the head to check it out.

Fortunately there was no damage.

Next time out I tried re-tuning it, and I got it to run somewhat ok, but I would always have some form of problem after a few minutes.

That is when I got the suggestion to check the head temp.


A friend came up with a laser thermometer and that is when I saw that the temperature was soaring.


Downunder I thing it was one of your sage posts, that I recalled at that time, from another discussion.

I remembered that the temperatures the engine head was attaining were too high compared to what was talked about in that discussion.


So I started richening both the high and low end mixtures until I got it down below 360 or so.

At this point the engine STOPPED cutting out after a few minutes.... however I had a real problem with it bogging down at idle and when moving the plane down the field for takeoff.

The engine was way too rich during and during one takeoff and the plane went in.

The components are awaiting a move to a replacement airframe at the moment, but I'm still worried about the overheating.