? For the engine guys

[3Dreaming]

Any thoughts on keeping a C-90 cool while inverted? A guy here is flying a clipwing with a C-90. It has inverted fuel and oil. When upright and flying normal acro the oil temperature is OK, but with extended inverted flight the temperature will climb up and beyond redline. He would like to do more inverted and outside stuff, but the temperature is limiting him. Tom

[barnstmr]

Re: ? For the engine guys

If it's CHT - Try adding a manually operated cowl flap door on the top cowl aft of the pressure plenum.

[Pearson]

Re: ? For the engine guys

Assuming the engine baffles are good, I would explore installing some sort of lip that extends forward from the bottom of the air intakes on the cowl to the prop line.

[Pearson]

Re: ? For the engine guys

STP lowers internal friction noticably! Is this a NEW engine? Is the timing retarded?

[3Dreaming]

Re: ? For the engine guys

It's oil temp that goes up inverted, but it is OK for normal flight. He is already using AvBlend to help reduce the temps. I think the oil is doing what it should and carrying the heat away from the case which is the sump when inverted.The airplane has one of the oilfilter adapters behind the #2 cylinder with extruded aluminum fins attached. I'm thinking maybe a blast tube on the filter. Tom

[NY86]

Re: ? For the engine guys

I'm thinking maybe a blast tube on the filter.

Put one on the oil screen housing, too. Problem is the oil sheds a lot of heat through the face of the oil tank. When inverted, this doesn't work...

[Pearson]

Re: ? For the engine guys

If he already has an inverted oil system, it should be a piece of cake to install an oil cooler.

[3Dreaming]

Re: ? For the engine guys

The oil filter adapter is mounted to the oil cooler pad. All of the exposed lines for the inverted system are on the suction side, and I don't think putting an oil cooler (restriction) on the suction side would be a good idea. Tom Tom

[resojames]

Re: ? For the engine guys

I flew a clip wing cub with a C-90 for years in airshows. The inverted oil system I used a flapper door in between the oil bulb and engine block. If he is using that type of system, then I don't think he will have much luck in reducing oil temps. It leaks a lot of oil into the engine block while inverted and it gets beatup pretty bad and absorbs heat off of the pistons. I tried a lot of things, but found it best to limit inverted stuff when outside temps were hot.

[3Dreaming]

Re: ? For the engine guys

It is using a Christen inverted oil system, so the oil goes into the top of the engine. Tom