ORIGINAL: highflyinguy
Latest hot find.
When I went to check out the needle valve assy that I got from Stuka, I found the "O" ring on the venturi was way too small in diameter and thickness. I replaced it with the one from the original OS venturi and checked out the spray bar which was clean and burr free. I then sealed the spray bar on both sides with Blue RTV silicone, set it down from 90 degrees, about 4:00, to the rear.
I think I may have found somthing important that was definetley wrong.
Ya know , I hope other newcomers lurking at this post, learn some things on engines and what great guys you are to help a feeble retread from the 50's. I wish I had named the post diffrently, but I was just trying to drum up some action from the members to post something.
Jerry
Whatever works works and it sounds that you have found that 'whatever'.
After reding over all the posts I need to interject a point for the new CLers that start in this world so strictly engrossed in RC as the only model aviation interest. OK so I went RC back in '71 from some 20+years of CL and FF, but CL stunt is still in the heart.
When I was a fairly competitive stunt flier back in 1960 - '72, I used the Fox .35, Johnson Stunt Supreme .35, the Super Tigre .40 (George Aldrich specials) and stock
Fox .40 Stunt engines, which I believe, if properly broken in, and run on 5% nitro, minimum of 25% castor, and a RC Idle Bar glow plug, was the best of them all.
Now my points:
1. 25%+ castor works wonders for the good ol' 2-4-2 engine run.
2. Replace any stock NV Assembly with either an OS or Enya 35-40 assembly.
3. Place the single hole facing REARWARD just out of sight. (This is the lowest point of static pressure in the venturi of
accelerated air flow.) IT WORKS. The biggest wonder was that only a couple others that I ever met knew about and used this
fact. I learned of it when a teenager from an old America's Hobby Center Hints booklet.
My one and only chance to make the NATs top 10 was the '71 Glenview NATs however I swayed to the Testors rep and tried the yet-to-be-released McCoy 40 grey-case. Fifth run on engine and 1st official was a barn-burner until after diving down from the 4-leaf, when she went to rat-race lean and ran for 11 minutes. Of course the 2nd official was far too rich and there went my last chance for glory. Don't it jus' make yer' eyes water????
You did notice that the OS NV, the Fox Superfuel, and the Fox Idle-Bar did NOT help me then!!! That K&B ringed piston/sleeve in the McCoy case just did not have the porting for a Stunt engine. I suppose there are some other requirements too. Ha!
BTW I still do 1/2A CL (all self designed) with grandkids in back yard where I can fly 52' lines. 'WE' also fly an original Fox .19 trainer, built in '85. and a Still Stuka, Fox 35 (built in '95) every so often there except the Stuka ain't so much fun on the short lines.[X(]