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I went to pick up a sonex yesterday in NC ,with aerovee aircraft is clean, trigear 145 hours fist problem overheats very easy if you try to clime it overheats very easy all baffuling is in place . second problem front oil leak could be front crank but not sure yet it was raining when i landed , can this be changed without splitting her case ? going to pick up with a trailer on saturday i feel its not safeto fly any distance.

SonexEZ wrote:I went to pick up a sonex yesterday in NC , aircraft is clean, trigear 145 hours fist problem overheats very easy if you try to clime it overheats very easy all baffuling is in place . second problem front crank shaft oil leak , can this be changed without splitting her case ? going to pick up with a trailer onsaturday i feel its not safeto fly any distance.

What engine ??

If it is an aerovee. FWIW I have been chasing an oil leak in the front end of the engine. I think I found the leak. I went and re torqued everything and found the distributor and breather block off plates loose. I also replaced the oil pressure sender and made sure that was tight. When I came back from Santa Paula the front right baffle at the cowl inlet was dry. Now I only have a small leak at the pushrod tubes. And no more oil all over the belly. I will monitor that leak and live with it if it is minor enough. That will be addressed if/when I need to remove the heads for something else.

DCASonex wrote:

SonexEZ wrote:I went to pick up a sonex yesterday in NC , aircraft is clean, trigear 145 hours fist problem overheats very easy if you try to clime it overheats very easy all baffuling is in place . second problem front crank shaft oil leak , can this be changed without splitting her case ? going to pick up with a trailer onsaturday i feel its not safeto fly any distance.

What engine ??

aerovee 2.1

In order to get an AeroVee to run cool, attention to details is important but to make a long story short I'd start looking over 3 key items:

1. Make sure your cooling baffles are not only there but seal well. Every small leak on the baffles can make a big difference in cooling efficiency.

2. Check and make sure your carb is set rich enough for full power climb. I'm not sure what sort of engine monitoring you have but if you have some sort of EGT monitoring I'd ensure your mixture is rich enough you don't see much over 1150-1200 degrees on climb out. If your EGTs get over 1250-1300, you can easily get high cylinder temps as a result.

3. Check your secondary ignition to make sure it's not advanced. You'll probably need to do this in cruise but follow the factory engine manual instructions to ensure your ignitions are timed and then try it again. After I adjusted my secondary timing my cylinders ran much cooler as a result.

Give those a shot and let us know how things go.

Define overheat. What is the CHT, EGT, and oil temperature. That may help in figuring out the issue. A few questions. Are the wheel pants and gearleg fairings installed? Sonex has said that this is the first step in eliminating over heating. It makes a very big difference. If you shut down the motor with the mixture does the RPM increase before the engine cuts out? If not you may be running too lean. My EGT's quickly climb when I have the aerocarb set on the lean side. Have you tried climbing out on just the primary ignition after getting the engine started? A secondary inition off even a few degrees can cause over heating.

Keith
#554

I have to return to South Carolina Saturday , going to remove wings for transport back to Florida , you all have some good items for me to check into i forgot to mention that i am also getting pressure out of the crankcase vent meanning something is blowing by rings ? The A&P who just did the annual should have flown it first I bet he was paid off to pass this aircraft , I also have to chase down the oil leaks

"The A&P who just did the annual should have flown it first I bet he was paid off to pass this aircraft "

I thought were also an A&P….. and as prospective buyer, maybe you should have flown it first and looked it over….. Just sayin' from one A&P to another.

maybe if i had worked on small aircraft in the past 25 years instead of 727-200 and 747 i would have had more knowledge to know what to look for as one A& P to another I beleaved the A&P just did an annual on this aircraft

SonexEZ wrote:I went to pick up a sonex yesterday in NC ,with aerovee aircraft is clean, trigear 145 hours fist problem overheats very easy if you try to clime it overheats very easy all baffuling is in place . second problem front oil leak could be front crank but not sure yet it was raining when i landed , can this be changed without splitting her case ? going to pick up with a trailer on saturday i feel its not safeto fly any distance.

There can be several reasons. When I was running hot it was almost entirely because I was running too lean. I had to change to a different needle in the AeroInjector and then do some trial and error. Once I did that all the temps dropped way down into the green. Way down! The baffling might not be sealing well. The super tin (metal baffles under the cylinders) could be misaligned. The cowl inlets and outlet might not be cut/sized properly. Is there an oil cooler? Bottom mount or top mount? Is there enough air getting to it? The secondary ignition might not be timed properly (there is a procedure to turn off the secondary while in flight to see if the temps go down). I wrapped my exhaust pipes with header wrap, and that seemed to help keep the temps a little lower. Other people may have some other ideas to check.