New Skymaster Owner

[Dan schultz]

Welcome

I am doing the annual on my P337 that I acquired in October, I am an A&P doing the work myself, will probably be 30k in parts and repairs without labor since the aircraft has not been maintained properly in the last 20 years, but in the end is a great aircraft. Mine is a 74 model, all three tanks in the left wing cracked, and assuming the three tanks in the right wing are also cracked, tanks are flimsy with no baffles.

Dan
N67S

[frank.oconnor19]

Owning this airplane is a labor of love. Learn to do some of the stuff yourself, will save you a ton, and you will learn more about the plane.

When my partner, John Cooper, and I purchased our plane, the rear engine was a problem for heat as well. We did a couple of things, that depending on how long your plane sat, I highly recommend.

1. Get the oil cooler serviced, this will help
2. If you can get the correct socket, John and Bruce( local mechanic) used a grinder to get the thickness of the correct socket thin enough to get on the Oil Cooler valve.
3. Make sure you plug the holes and gaps in the rear engine baffles.

Be a crazy person about keeping the engine cool enough, slow dow a few knots, make the engine much happier.

And for others here, correct me if I am wrong, but the oil pressure has everything to do with how well the propeller feathers. Change the oil, have it looked at.

Finally - where are you based?

Frank

[TomM]

Frank:

I am totally planning on doing as much as I can. I am a highly capable mechanic/engineer. The issue is that I am in Iowa, and the plane is in Oklahoma. I have been troubleshooting with the mechanic down there. I asked him to pull the oil pressure relief valve as it is located before the oil cooler. So if it is dumping oil, there is less oil getting cooled leading to higher temps. See the attached pics. Needless to say, this was a good call. Cleaned the port, ordered the new style adjustable relief valve. Since I will not be back down there for a week or more, I am going to have him pull the oil cooler and send it to QAA for an exchange.

On the propeller side of things, we have to keep in mind that constant speed props work just the opposite of feathering props. CS props rely on pressure to INCREASE the pitch, and feathering props rely on pressure to DECREASE the pitch. That is why if you have a full engine stoppage, you can still feather the prop on a twin. In addition, the governor has a high pressure pump in it, so as long as it gets oil, the governor will boost the pressure to the prop. The SUPER NICE guys at H and S propeller have worked on the props in the past so I called them. He said it is very common to have to adjust a screw on the side of the governor to allow the prop to de-oil faster in feather mode. He said that my prop feathers at a higher RPM because the counter weights in the prop are helping push the oil out. He gave me a test to run, but wants me to send him a picture of the governor so he can walk me through the adjustment.

I am headed down to OK to putts around with it this weekend. I am still very excited about the whole deal. I totally expected this to be a labor of love, so no worries there. I just wish people were more up front about issues instead of trying to hide them. Even if I can't fly this weekend, I am totally stoked to sit in it and make engine noises........you all cant see it, but I have a huge grin on my face right now!!

You guys are great!

[patrolpilot]

Welcome, Tom! You will get through this and be on your way! Any pictures of your airplane?

[TomM]

Thanks for the welcome! Here is a pic......its needs a splash of trim color to offset all that orange! Now you guys dont start calling it the pumpkin.....

[JAG]

Tom - So awesome, thanks for sharing the picture.

I think you are on the right track with the oil pressure relief - that thing looks badly scored and likely not letting the spring do its work. I once had an oil pressure relief valve stick open (on a single engine aircraft). Just after takeoff, turning out of the circuit at about 900 ft AGL - I look down and I have about 5 psi of oil pressure. NOTE:Was doing a break-in flight on the engine from overhaul, and this was about hour 4 of flying (multiple take-off and landings).

Anyway, I reduced throttle and pressure went to zero, temps normal, no oil on windscreen...WTF. What seemed like a minute was likely only a few seconds, I started my turn back to the airport, made a radio call and decided to shut the engine down rather than run it without pressure. After gliding in for a safe landing and letting the adrenaline wear off, I started troubleshooting all the usual suspects. Last thing I removed was the pressure relief valve, and that little poppet did not slide out easy (which it should). Small amount of scoring was all it took for that thing to hang up. Replaced it and the housing - never had a problem since.

Point of my story is - chase all the easy things first. Most of my oil pressure or oil temperature related issues have been oil coolers and pressure regulating valves...and surprisingly, after they have been overhauled!!!! I only install new oil coolers now.
Jeff

[patrolpilot]

Originally Posted by TomM

Thanks for the welcome! Here is a pic......its needs a splash of trim color to offset all that orange! Now you guys dont start calling it the pumpkin.....

Dude, I love it!

[YankeeClipper]

I believe that would be the "Jet Glow" pumpkin, if memory serves.