Hello,

My last 3 engines (TT GP42, TT 36Pro and OS 32Heli) all got black build up inside that hart there preformance (I had to get read of the GP42 because of that). I know that this is a simptom of engine gets too hot and/or the oil starting to brake.
I try to operate all this engins as reach as posible (any richer and the engines won't operate smothly) on 5% nitro (15% for the OS32Heli) Omega or Red Byron fuel right from the start and all of them had this broblem.
Is it the fuel (low oil consetration or oil that brakes in low temps) or I just got bad luck with my engines.

Thanks,

You are probably running the engines too rich, and the castor is gumming up on you. The black stuff is the carbon from the castor burning. You might want to try a fuel with all synthetic oil, or less castor.

Hi!
The carbon build-up you speak about is a symptom of running castor oil in your fuel at a too lean setting (to hot).
Carbon build-up will always increase as you set the engine leaner...not richer!
A remedy is to use a mix of castor oil and synthetic oil or just all synthetic oil.
Over here in Europe many of us use 15% all synthetic oil ,or less,in our fuel.
(French racing brand: Motul Micro, or German, Graupner: Aerosynt 2 and Aerosave).
Regards!
Jan K
Sweden

You can get a carbon film from running too lean, but you have generally already trashed the engine from running too lean before you get enough carbon build-up to notice.

Carbon build-up is typically from running a too rich high speed mixture.

Lynn

Hi,

Till now I used fuels containing castor only or castor mix. I'll try to switch to sintetic oil only and see if it will help.

Thanks.