A new Skymaster Owner enters the forums

[JeffAxel]

I had GAMIs on my P337 and the engines ran fine with them. Ran them at 65% power, 23-24gph total in cruise which got me a TAS of 185 in the high teens with cool temperatures even in the summer with the cowl flaps closed. My P337 had intercoolers, air conditioning and VGs so was slower than some, you might do better TAS wise. The best part was the cylinders looked clean as a whistle when we borescoped them. Never had to clean spark plugs.

[mshac]

Originally Posted by JeffAxel

I had GAMIs on my P337 and the engines ran fine with them. Ran them at 65% power, 23-24gph total in cruise which got me a TAS of 185 in the high teens with cool temperatures even in the summer with the cowl flaps closed. My P337 had intercoolers, air conditioning and VGs so was slower than some, you might do better TAS wise. The best part was the cylinders looked clean as a whistle when we borescoped them. Never had to clean spark plugs.

Air conditioning is the ONE THING this plane doesn't have that I REALLY wanted. Intercoolers, winglets, STOL kits, and VG's are all cool (no pun intended), but when you walk outside into a North Texas August day - 100 degrees, 60% humidity - its AIR CONDITIONING your body and mind are wishing you had!

First flight, I took off south of Denver from about 6700' on a 90 degree day. Wouldn't want to do that in a non-turbo! Heat wasn't really an issue leaving Denver climbing to 17.5K, but cabin temps were beginning to get a bit uncomfortable during the last minutes of the flight as we descended down into the Texas heat to my home airport at about 700' elevation.

Whatever airspeed and useful load you may give up is WORTH IT to have AC!!!

Regarding GAMIs, do you lean to peak TIT, or wait for the last cylinder to peak as you lean for LOP operations? I got about 28 GPH, but I was feeding it fuel like a drunken sailor on shore leave. TIT never went above 1400. I actually ran the rear engine a bit richer to keep its temps in line with the front. Probably should've just opened the rear cowl, or just accepted the temp diff. CHT's were all well under 400, so it wasn't a huge deal, just 10-20 degrees higher in the rear.

[mshac]

Ok, its not much of a mod, but I repaired the broken courtesy light circuit in the overhead clamshell door, and installed a 24 volt LED bulb that really lights up the cabin entry area, and runs cooler and uses fewer amps. You need a special two-contact type bulb - Here's a link to the bulb I used: https://www.amazon.com/dp/B00BZWLK6U..._hxPmFbJ27V21B I'll post up some night pics this evening.

[Learjetter]

Originally Posted by mshac

Ok, its not much of a mod, but I repaired the broken courtesy light circuit in the overhead clamshell door, and installed a 24 volt LED bulb that really lights up the cabin entry area, and runs cooler and uses fewer amps. You need a special two-contact type bulb - Here's a link to the bulb I used: https://www.amazon.com/dp/B00BZWLK6U..._hxPmFbJ27V21B I'll post up some night pics this evening.

Nice! Welcome to the boards. Wealth of info here, a fantastic resource.

My courtesy light in the overhead clamshell door is also inop (someone cut the wires where the door meets the fuselage). I'll try your bulb suggestion, if I can figure out how to get voltage to the wiring harness.

[mshac]

Originally Posted by Learjetter

My courtesy light in the overhead clamshell door is also inop (someone cut the wires where the door meets the fuselage). I'll try your bulb suggestion, if I can figure out how to get voltage to the wiring harness.

Don't forget, there is a 1A glass fuse under the front cowl on the pilot's side that feeds the courtesy light circuit. Mine was blown, I bet yours is too.

[Rick Erwin]

Welcome to the Forum!

You have purchased a very nice-looking plane! I'm anxious to see some more pictures.

I have a 1976 FT337GP (the French equivalent of a P337G). I'd be happy to help you in any way I can!

I am dealing with a courtesy light issue right now. I purchased the LED replacement bulb last week. My current issue is - someone cut the wires at the door frame / window frame. Would you mind snapping a picture of how your courtesy light wiring gets from the fuselage to the upper door for me?

Thanks in advance!

Rick

[mshac]

I'll see what I can do about the pics of the courtesy light wiring. Here are some of the new LED, the panel at night, and the rear engine access port. Sorry about the poor focus on the night shot.

Question - why is there a light in the center of the dashboard that shines in your eyes? You can see it in my panel shot. Is there supposed to be a red lens? Because I can't imagine why you'd want it on to kill your night vision.

[Learjetter]

Originally Posted by mshac

Don't forget, there is a 1A glass fuse under the front cowl on the pilot's side that feeds the courtesy light circuit. Mine was blown, I bet yours is too.

Thanks! I checked the fuse—looks OK. The courtesy lights in the headliner above the 2nd row appear to work, as does the dome light. But no voltage on the wires headed towards the clamshell door, and the pilot map lights are inop.

On the plus side...the panel lighting is terrific!

[Rick Erwin]

Here are some pictures of the lens holder with dimensions. The characters need to fit within the frame on the backside so they'll show through.

[ljmolina]

Originally Posted by Learjetter

Thanks! I checked the fuse—looks OK. The courtesy lights in the headliner above the 2nd row appear to work, as does the dome light. But no voltage on the wires headed towards the clamshell door, and the pilot map lights are inop.

On the plus side...the panel lighting is terrific!

Today, im on the same mission... Where did they route the positive wire on the door for my courtesy light? I looked all around the piano hindge and for the life of me ai cant see how they routed that wire...also my map light is also not working either...but one thing at a time....

Previous owner hid the courtesy light behind the door panel, why IDK... but im not getting any power to it...i checked the fuse on the firewall fuse holder which is good.

[Jerry De Santis]

I have 1975 P337G with Boots, Riley A.C. Riley inter coolers, spoilers etc. been flying this plane for 22 years. I found operating rich of peak has given me best performance and longer component life. I operate at 27 to 28 GPH. As for air cond. I suggest you check out an electric drive unit. There are several on the market. The alternators in the Skymaster are heavy duty and can carry the load. Also, if your plane is not equipped with spoilers and you intent to fly in the teens all the time, with spoilers you don't have to change engine setting when descending. Thus, don't have to be concerned with engine shock cooling. I almost always fly with engine settings of 2450 RPM and 31 inches.
Good luck and enjoy your new plane.

[mshac]

Hello Jerry. What a nice 337 you must have!

At 17.5k, I ran 2450 but was getting more like 29". This was a very hot day, even at that altitude air was still in the upper 40's. Should I see higher MP on a colder day, all else being equal?

Another question for an experienced owner - what does "bootstrapping" mean in reference to the twin-turbo pressurization system? This is a new term for me.

[JimC]

Originally Posted by mshac

Hello Jerry. What a nice 337 you must have!

At 17.5k, I ran 2450 but was getting more like 29". This was a very hot day, even at that altitude air was still in the upper 40's. Should I see higher MP on a colder day, all else being equal?

Another question for an experienced owner - what does "bootstrapping" mean in reference to the twin-turbo pressurization system? This is a new term for me.

If your throttles are full forward, you should have no trouble getting MP higher than 29" at 17.5. You have a significant induction leak if you can't.

Bootstrapping is easier seen & heard than explained:
https://www.youtube.com/watch?v=nBJmspBZes4

https://www.avweb.com/ownership/turbocharging-systems/