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N179ES got its A/W Cert in July 2007. I bought the plane in November 2021.
All in all the inspection is going well.
Certainly a good opportunity to clean everything up well and to make sure that everything is as it should be.
80 hp Aerovee 560 hours total rebuilt 2 years and 100 hours ago - leak down compressions all 77 or better.
a bit oily around the hoses and the bottom mount oil cooler. I have a top mount and will change to it.
Q #1. Would you do the bypass plumbing and keep the oil pump /cover or change out the pump. Is there a replacement cover that will work that doesn't require the plumbing?
This engine has the EMPI Mini-sump oil screen/filter and I think that is an improvement over the standard VW oil screen.
Q #2. Anyone agree or disagree with that.
I have the older style aerocarb. I spent a lot of time in spring trying needles and tuning and the engine runs quite well now. It starts easily, takes throttle well and gives me about 3100 rpm WOT at runup. I think I have a 2.5 needle installed. At idle and low rpm taxiing I get a substantial rpm increase and smoother running with the mixture almost all the way to cutoff. Idle is a bit rough and under 800 rpm. When leaned it increases to around 900 to 950. In flight at cruise I lean to about 1/2 way out and gain about 100 rpm. I take off and climb at full rich - BUT - if I remain at full power (beyond about 500 ft AGL) the exhaust temps will go above 1450 and set off the alarm on my GR EIS. Cylinder head temps stay below 375. I am in So Wisconsin field elev 850' MSL. Both my top and bottom spark plugs have quite a bit of black carbon on them. No significant difference top or bottom. They are gapped correctly .018 top and .032 bottom. The engine is set up for 8 to 1 compression ratio and I have been running strictly 100LL. I have auto fuel available with no alcohol and I could run a mix. I made a rather deluxe sight gauge so I pay no attention to the GR EIS fuel quantity which has never been accurate.
Q #3. Is the black carbon more or less normal with 100LL I'm thinking the correct answer to that is NO.
I have read the recent posts about aerocarb needles. I am not competent to make or modify them. My assessment is that I am running rich most of the time but not rich enough to keep the EGTs below 1400.
I have conventional gear (tail wheel) with 6" tail wheel. My right main looks to be perfectly parallel to the direction of the fuselage. My left main is anlgled out slightly. I estimate less that 5 degrees. The plane handles well on grass and on pavement. When I bought the plane last November the left main had more tread wear in general and more wear to the inside. I think that jives with the alignment I am seeing. It doesn't appear that there is any way to adjust the alignment. Top and bottom bolts are AN hardware.
Q #4. Any suggestions?
Thanks for reading my ramblings. I welcome constructive suggestions and feedback.
Tom

Tom,
Sounds like a great condition inspection. Either a bypass loop or new pump would work fine. In your situation I'd personally lean to a new pump, less weight, stuff, and places to leak.
https://www.sonexaircraft.com/eshop/car ... g=Oil+pump

I have the top mounted oil cooler, the pump with the plumbing, and an external oil filter. Anything is an improvement over stock. Technically not required and it adds weight.

Where in Wisconsin are you?

Thanks Brian,

I am located at 88C - Palmyra Municipal, not far from you.

Tom

Awesome. That's in my flight test area. I'll have to go there sometime.

tom.corso wrote:It starts easily, takes throttle well and gives me about 3100 rpm WOT at runup. I think I have a 2.5 needle installed. At idle and low rpm taxiing I get a substantial rpm increase and smoother running with the mixture almost all the way to cutoff. Idle is a bit rough and under 800 rpm. When leaned it increases to around 900 to 950. In flight at cruise I lean to about 1/2 way out and gain about 100 rpm. I take off and climb at full rich - BUT - if I remain at full power (beyond about 500 ft AGL) the exhaust temps will go above 1450 and set off the alarm on my GR EIS. Cylinder head temps stay below 375. I am in So Wisconsin field elev 850' MSL. Both my top and bottom spark plugs have quite a bit of black carbon on them. No significant difference top or bottom. They are gapped correctly .018 top and .032 bottom. The engine is set up for 8 to 1 compression ratio and I have been running strictly 100LL....................My assessment is that I am running rich most of the time but not rich enough to keep the EGTs below 1400.

Tom - this is pretty close to an identical write up of how my 550 hour Aerovee runs with a 2.5 needle at sea level. I also have a cold air inlet directed at the air filter to help keep things running when the engine is hot and under the cowl is suddenly full of warm, thin air after landing and slowing down.

An alternative to riching up to contain EGT's after take off - I have found pulling back 100-150rpm rpm has the same effect in containing EGFT's and allows you to stay lean. Probably not a bad thing anyway - thrashing the engine full WOT is not so good for engine life.

I lean aggressively after starting - if only to keep the lead off the plugs and the same after landing. That way I get gray plugs. If I forget to lean after landing - even a short taxi will blacken them pretty quickly.

Also note that EGTs are not indicative of the level of stress on the engine and are merely an “average” temp as the exhaust pulses cause rapid temp swings. The exact distance between the exhaust and the probe can also result in higher or lower readings from cylinder to cylinder and engine to engine.

For more information on this, I highly recommend any of Mike Bush’s writing or webinars on EGTs.

Take care,

—Noel

Hey Tom! Your Sonex was famous once:


Nice looking airplane. I sent you contact info via PM. Would like to visit when I get a little further into my flight test program.