I have 2 MDS 148 's. I have had sucess with Byron's 5% fuel. I also have an oscellating pump connected to them. The units tend
to overheat when cowled. Try larger exit air exits and maybe air deflectors to direct the air towards the head.
Another member of my club has had the same problems that you report. Try running without the cowl to confirm its a heat
problem. Again my engines are very fuel brand and nitro content, fussy. 15% caused it to overheat. I noticed that my engines
are much hotter than other brands of engines ( boils spit ) This is why I think they have a heat issue. Also there is not as much fin
area as other brands of engines. Now in the process of constructing some internal cowl fins to direct the air flow. I hope this information is of help.

Wayne Marcy
[email protected]