582 high engine temp

Re: 582 high engine temp

by Michael Regan » 13 years ago

Michael Regan

5 96 0

Dennis,

I have now all blades set at 18 degres and static WOT at 6400, so I am supposing half a degree less will do it. It is also tracking perfectly, both in lateral and longitude aspects.

Because its taken me about 15 tries to get it this good, I really don't want to undo it all again because ...

1/ I will be ordering a new one and so it will only be a temporal installation.
2/ I am thinking that all I have to do is watch I dont over rev the motor and it should be ok till I get the new prop.

So, my question is... will this suffice till then if I keep an eye on both the rpm and the pitch angle?

Thanks mate.... Mike

Re: 582 high engine temp

by Dennis Richardson » 13 years ago

Dennis Richardson

1 153 177

Hi Mike
6400 rpm static will leave your takeoff performance lacking and you will be running high rpm. You will be operating on the back side of the performance curve. A 2 cycle engine that is not operating under adequate load can suffer from a lean air/fuel ratio under some conditions, this could result in engine failure. You have gone this far, don't quit now. Your best performance overall will be something real close to 6250 rpm static. I would start there, I am sure you will find the sweet spot somewhere between 6200 and 6250.

Dennis

Re: 582 high engine temp

by bill martin » 13 years ago

bill martin

10 757 11

Mike,

Dennis is right, you need to be as close to the power curve as you can get to realize the full HP pf the engine. You are, however, much better off than you were before you repitched. 6200 to 6300 should be your static rpm with your aircraft. This varies a little with each machine. High drag airplanes like powered parachutes can often run close to full RPM in static tests whereas high speed, low drag aircraft may run much lower static RPMs. Use Dennis' advice and pitch the prop to give you the maximum recommended continuous RPM during climbout.

Two cycles are extremely susceptible to weather so dont be surprised if your RPMs change as much as 100RPM with weather changes.

Don't know how you are pitching the prop but a good trick I use is to cut a notch in the end of a board which will fit the blade close to the root. This will give you the leverage to twist the blade in very small increments when adjusting.

Back to the radiators. If all this still does not lower the temps, you might try to find some thicker rads if you have no room for larger ones. Another solution might be to use a waterless coolant which gives you more cooling efficiency.

Bill.

Re: 582 high engine temp

by Michael Regan » 13 years ago

Michael Regan

5 96 0

Dennis

Got all 3 blades set close to 19 deg... will test it Sunday. Got my fingers crossed.

Bill
I just use my hands to twist the blades which means the hub has to be pretty loose. Usually 2 x 360deg turns of the nuts does it.

I have already got a guy in the wings ready to make a thicker rad.

Mike

Re: 582 high engine temp

by Michael Regan » 13 years ago

Michael Regan

5 96 0

Tested today in OAT 75 deg. All blades at 19deg pitch and static rpm WOT was exactly 6250 rpm.

Climbing at 800 ft/min... 55 knts... WOT.... OAT 75 deg....rpm only 6100 ... overheated again.

What I dont understand is if static WOT = 6250.... then why climb WOT only 6100? Could it be the warmer OAT? I checked blade pitch again and there was no change.

All out of options now it seems.....Mike.