Overheating Problems

by Bill Herrett

Many of the club members at different times have mentioned how their Merlins run hot or even boil, so with this in mind I have been experimenting with mine.

Normally my temperature Gauge needle sits in the middle of the gauge, however as the engine is boxed in I decided to try taking the panels off (inner wings) and try it without, this made quite bit of difference, but left the sides of the engine exposed.

What I have now done is cut the centre out of the side panels and replaced it with mesh (used by plasterers) and am pleased to say that running up the A12 for 40 miles at 50mph the temperature gauge has dropped by 10 to 15 degrees.

I have my usual expert diagram below.