Cox TD .010 problems with running -- Update

I was able to get some 30% nitro fuel from the local model race car hobby store. I added enough castor oil to make it 20% oil and 25% nitro. Engine ran like a charm and easily ran through the whole tank of fuel with no problems.

As for the lack of adjusting the needle to get it to run lean or rich, I discovered the spring on the needle prevented the needle from going to a new position. If I adjusted it a 1/4 or 1/2 turn, the spring forced the needle back to its original position, thus appearing as though the fuel mixture could not be changed. With a bit of fiddling, I could get the needle to go to anew position and adjust to run rich or lean.

So these little guys really need the high nitro content to run well. Also, the having too much oil may be a problem too.

Thanks, again, everyone who had suggestions.

Eric

Eric,

Two solutions to the spring problem are 1) File a "flat" spot on the end of the spring so the wire won't dig-in or 2) install a steel flat-washer so the spring won't dig-in. Both methods work.

George