From a point at sea, to the circles of your mind, this is hugh:

In message , Stewart
Hargrave writes

Tried both reducing and increasing spark plug gaps.

What gap on your plugs?

I've tried 28 thou (standard for petrol)
25 thou (what I usually set them to for LPG)
22 thou
I think I also tried 20 thou, but this is getting to be a very small
gap.

Currently set at 25 thou

None of the changes made any noticable difference.

I have been thinking that a hotter plug may do something.

It seems to me that the problem is centred around number 4 cylinder,
and that somehow the spark is not igniting the fuel properly. As the
fuel mixture must be the same in all cylinders, and there seems to be
a big voltage across the plug, I guess it has to do with poor spark
formation somehow, but I haven't come up with a plausible reason yet.



--

Stewart Hargrave

A lot faster than public transport


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