i have just finished breaking in my engine in my kyosho nitro viper GT. im new to nitro rc and im concered that the engine may be running to hot. what is the normal operating temper ature for a glow engine of this size? should i realy be concered about it ?

i have a .32 marine in my jet stream 1000 that i can usually touch after a 20min run w/o burning my hands/fingers. i believe the test is to put a drop or two of water on the engine. if it boils away instantly, the engine is above the boiling point of water (to hot). if it just slowly (but still kind of quickly) evaporates, you are good to go.

thanks. how is your engine cooled? my O.S. uses the prop wash to force water through the tubing to the engine head. i dont think that it is really effective enough to keep the engine cool enough. am i just under estamating the effectiveness of this cooling system?

I can't think of a more effective way of cooling the engine. I believe our two boats probably share the same outdrive system, black plastic that holds the prop shaft/rudder and turns the whole thing as one unit? There is a black plastic water pickup right behind the prop on mine.

Pull the hose off and blow through it, make sure you don't have something stuck in it. I think one of the things that keeps my engine quite cool is the fact that for some unknown reason, the water is dumped right into the muffler after it comes out of the head. And this isn't a special water cooled muffler... its listed as a helicopter muffler by tower hobbies if you want to replace it.

The only other way to pickup water is to have a pickup dipping into the water in front of the prop, right at the hull. Since its not in the prop wash, nothing is really forced in so you won't have much waterflow at low speeds... and probably about the same or slightly less at high speeds.

Any cooling is better than no cooling, some things to look at are how lean are you running you engine, if you run it richer it will run cooler, and will prolong the life of the engine. The method of water cooling you have is pretty efficient , you should try and set up a running tank at home so you can put your boat in a strap it down and run the engine, check the temp of the water coming out, it should be warm, not boiling hot. You'll know if your engine is too hot if it seizes while running or if it burns things around it in the boat.