N 39991 Almost Ready to fly again

[KewFlyer]

All:

N 399991 is almost ready to fly again after two years of slow and painful ($) work. Estimate to have her ready by the 4th of July week end for her first test flight. Then work on the details, aileron rigging, etc...

[Mark Julicher]

Re: N 39991 Almost Ready to fly again

Looking good Ralph!
We eagerly await first-flight pictures.

[Jim Herpst]

Re: N 39991 Almost Ready to fly again

I almost purchased that plane from Ernie Postal . He died before I could come and get it. I was planning on a new boot cowell and new cowel which were both a real mess. The rest of the plane was preety doggon nice. It was the last tube and fabric plane the School kids did over at The Pittsburgh Institute of Aeronatics ( PIA) It was done with "Miss Pittsburgh" a mail carier that was last hanging in the Greater Pittsburgh Air Terminal.

What did you do to 39991 ?

[KewFlyer]

Re: N 39991 Almost Ready to fly again

Jim:

PIA did a great job restoring this ship. The sad part of the story is that when the restoration was completed, it sat unattended ( wings were removed and engine pickled due to the owner's illness) until about two or three years ago when a fellow from WV bought it and flew it a few times. So actually, this ship has sat since restoration. Over these years it developed some rust around the tailwheel area that required attention ( sat with the tailwheel on the ground and we assume that water may have condensated or...? into that lower spot), as well as new wing root covers, aileron and wings rigging ( flew sideways with the tail wanting to come around from the left( Big ?)), unfreeze pulleys (two were replaced, two or three more might also), unfreeze the trim system (still working on it), engine inspection ( 75 HP upgrade at overhaul: 10 hrs SMOH, starts on the first pull. Case Mags, metal cruise prop), repack bearings, get the breaks working again and other items that require attention before it's ready to fly again. Has fabric doors that need some work in order to close and keep a tight fit. The fabric is in like new condition as well as the wood ...very well varnished and NO living creatures nor evidence of them was found either!!. So nothing to worry about, just the usual maintenance that these planes may require when left unattended over time. It has new sealed struts, new tires and a rebuilt cowel painted with a different white color than the insignia white on the rest of the plane...this may have to wait.
If we dont make the 4th of July date, it will be sometime in late August-early Sept when she may go up. other than the above, we think that she will be a good ship for many years to come.

Thank you for your interest. Will post pictures when she is ready.
Best
Ralph

[KewFlyer]

Re: N 39991 Almost Ready to fly again

Fly again !!!!!
Test flight last week end went well but still needs some rigging of the wings. Ailerons are flush with the wings...no droops...just straight. Something does not feel right with the wings...holding rudder and aileron at times...then adjust the wing struts and is too much... or too little or the wrong direction= got worse...quite a job to get it right!!!. At this point, I take any suggestions that the tribe may have on rigging the wings...pointers or any other help. I'm ready to start the whole process again from scratch.
The engine has a knock ...A&P-IA said that might be a stuck valve in one of the cylinders. Added MMO to the oil and fuel...he claims that it may get it loose. We'll see.
Other than that, it flies great. What a nice feeling to be back in the air.

[Pearson]

Re: N 39991 Almost Ready to fly again

Did you start off with the method shown in the Service Manual for adjusting the wash out? My plane had a heavy wing when I bought it. I started out by using the technique in the Service Manual, but it still flew left wing heavy. If you use rudder to keep the ball centered, you will know which wing is heavy by the force on the controls. The heavy wing has too much warp to it. You can adjust it out by letting out the screw at the end of the strut, or tighten up the screw on the other side. After I got it to fly straight and level I did several stalls. It stalls straight ahead and flies level with no force on the controls, so I am happy.

[M Towsley]

Re: N 39991 Almost Ready to fly again

Ralph,

I will preface this with only what I have experienced regarding a stuck valve. If it is stuck open, your engine will not generate enough power to fly. I was out-of-town many years ago with the L-2 and thankfully Tom Baker happened to be there when it stuck right after we started it. Rope trick unstuck it and then I used MMO after. I still had to pull the valve and clean the crap out, but used MMO after and never had anymore stuck valves. This engine had digested a diet of 100LL only for many years prior to my buying it whereby I then ran mogas while I had it.

I am not sure if a valve can temporarily stick while running to create a knocking sound. More experienced folks will have to respond to that. Good luck!

[KewFlyer]

Re: N 39991 Almost Ready to fly again

Richard:

Thank you for sharing. We did follow the Service Manual since this was the only available method to install the wings correctly.
Interesting point is that when the wings were removed, we found regular washers ( 3 of them) on the back attachment point of the right wing only!! = puzzled. We commented that possibly it was an adjustment made to correct a heavy wing or... who knows. We did the wing strut screw dance on both wings a few times but still is not flying hands off. We will try again this week end setting both struts at the length. We also ran a string line from wing tip to wing tip to check for alignment and to verify if one wing was higher than the other one, as well as on the leading edges. All checked out within some limits. We think that the left wing was lower than the right wing [ flat floor and both tires at the same air pressure and a bubble level place on top of the windshield metal strap= it was level] on a visual check.
Back to square one on Saturday, with temps in the 100s by afternoon... (Test flights in the morning only). Will be fun.

[Buell Powell]

Re: N 39991 Almost Ready to fly again

[QUOTE=KewFlyer;65727]Fly again !!!!!
Test flight last week end went well but still needs some rigging of the wings. Ailerons are flush with the wings...no droops...just straight. Ralph--they should have about 1/4" droop when not in flight-so you might want to adjust the turnbuckles to loosen them before adjusting the washout.

[KewFlyer]

Re: N 39991 Almost Ready to fly again

Thanks Marty.
Apparently the MMO should do the trick. The engine develops fine but we can hear this knocking sound like metal on metal.
We will let the MMO do its trick for a few hours over the weekend and see if it corrects itself. Otherwise, "rope trick" or ....?
Regards
Ralph

[mhorowit]

Re: N 39991 Almost Ready to fly again

When can I come out and see the beast? The guy on the field your AP? -Mike

[KewFlyer]

Re: N 39991 Almost Ready to fly again

Mike:
We are doing the work at Petersburg, VA at Frank Isbell & Ross's shop. Fine people & quality workmanship work. Very pleased and highly recommend them for any type of work from vintage to modern planes. Once the wing heavy/washout and aileron issues get resolved as well as the "knocking" in the engine, I will get the plane back to Warrenton, VA. Hopefully in the next few week ends. I would still need to do some cosmetic work inside, as always. will contact you when is back in the hangar. No Oshkosh this year .

[crispy critter]

Re: N 39991 Almost Ready to fly again

the leveling line is not the windshield strap....you will not get a correct level line here. To level the airplane horizonally(wing tip to wing tip)you should place the level on the bar that the top back of the seat sling attaches to. The fore & aft level line will be the horizonal stab mounts. Also, I've never heard a stuck valve knock before....be careful.

[Guest]

Re: N 39991 Almost Ready to fly again

Last year I had a noise that sounded like a tapping with a small hammer while propping or during engine shut down.

I checked mag and cam gears; nothing. Looked for loose items;nothing. Checked valve clearand and tappets, rockers etc. ; nothing.

Had one jug that burn't oil. Pulled that one and checked ring gap- oil ring gap was very large replaced rings, all else on the piston, rings and cylinder was within new specs.

Also checked the valves on that jug - exhaust valve stem was covered with carbon and would not move freely. Cleaned the stem off and cleaned the guide bore with a rifle bore brush until it worked freely.

Reassembled and the engine ran fine, idled better (down to 375 rlm smoothy) and the noise was gone.

Maybe I had a "valve knock"?

Dave

[KewFlyer]

Re: N 39991 Almost Ready to fly again

Kevin & Dave:
Thank you for the advice on the engine knocking.
I'll pass this info along to the IA.

Thanks Buell for the 1/4 " aileron droop. They are level with the wing right now.