Walther

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Does anyone know if they make a cooling fan for a Zenoah G38?

BarracudaHockey

My Feedback: (11)

Yup. It screws on to the front of the engine, it's called a propeller

Seriously, what are you trying to accomplish?

Walther

My Feedback: (1)

I saw a cowled engine some where that had a cooling fan on the engine, I thought that was a good idea.

STUKA BARRY

Now that's some kinda funny right there............

STUKA BARRY

Zenoahs are industrial engines, they can handle the heat, especially the G-38.

3136

All you need is airspeed, correct ducting/baffles in the cowl, have a look at this http://www.rcuniverse.com/forum/m_11071695/tm.htm
Sadly the thread starter has since passed, so you can't ask his advice anymore but there is enough information there to gain from.
The Zenoah really shouldn't need a lot of help in cooling, as their cooling fins are extremely larger than most rc engines, so cooling is rarely a problem with them.
What plane do you have it in?

Walther

My Feedback: (1)

I am thinking I would put in a Rearwin Speedster.

3136

I wouldn't worry, just open up behind the engine for hot air to exit, if you put a downward spoiler or use louvers it will extract the heat well.