65hp Cont

What’s the best on stock wheels and brakes, 8.5? STC needed?

Older 3-24 tailwheel, can I add a pneumatic tire or do I need to go full 3200?


Thanks all


Also read this

“ Upgrading the Stromberg Carburetor for 75 HP

The Stromberg NA-S3A1 carburator to increase to 75 hp. I have already retimed the mags for 29 and 32 degres spit timing. this gave me 150 more rpm during full static engine run.
The venturi for the A75 is 1 5/16". Main metering jet is a #46 hole and the main airbleed needs to be a #60 hole. The specs for the carb are in the C75-0200 overhaul manual”

NineThreeKilo wrote:..... Older 3-24 tailwheel, can I add a pneumatic tire or do I need to go full 3200? ...

I don't think you can (legally or physically) change to a pneumatic tire on a Scott 3-24 (aka 2000) tailwheel.
A cheaper alternative to a 3200 might be a Maule P8A or P8B pneumatic,
friends who run them tell me they work well on lighter airplanes like a champ.

Thanks, I had some interesting experiences with the Maule tailwheels when I was instructing in planes with them.

Might have been a rigging thing but they loved to shimmy more than the older or newer scott

Might just keep the 2000 on for now I guess


Also any good areas to look at on a 7AC prebuy, it’s still got the old eisman mags?

I have Eismans on mine and so far so good. Had one issue, but that was a loose wire in the mag, apparently from poor re assembling from the last overhaul. Parts are still available as far as I know. As for areas to look at , obviously make sure the spar inspection has been done, but other than that, generally the same as any tube and fabric airplane. If possible take a look at the oleo’s for leakage. The logs, will tell the better story. I would also look at the fuel valve for leaks, they are an easy fix, but a fairly common issue. I went from a pneumatic tailwheel back to a solid and am happy with it.

Pete

Thanks, thinking I’ll keep the solid scott

Looking closer at the mags then seem pretty well built, but we shall see, run up saw 50 drop R 75 L, so within spec, but I think the timing to be dialed a little better to the book 30/30



Side note on an older plane, 3” N numbers on the vertical just above the horizontal stab is best I can do?

Was going to put them under the horizontal stab but seems if on the fuselage they need to be between the trailing edge of the wing and leading edge of the stab

Also seems 2” only works if the plane was never repainted/covered, so don’t think that will work


Any good online source for someone who does good vinyl?

I've used http://www.aerographics.com before and have had good luck with the graphics.

NineThreeKilo wrote:.... Side note on an older plane, 3” N numbers on the vertical just above the horizontal stab is best I can do?
Was going to put them under the horizontal stab but seems if on the fuselage they need to be between the trailing edge of the wing and leading edge of the stab
Also seems 2” only works if the plane was never repainted/covered, so don’t think that will work
Any good online source for someone who does good vinyl?

2" numbers are OK of the airplane is at least 30 years old, or an experimental, per FAR 45.22:

https://drs.faa.gov/browse/excelExterna ... pened=true

FAR 45.25 addresses location:

https://www.ecfr.gov/on/2018-03-06/titl ... tion-45.25

FAR 45.29 addresses size & width:

https://www.ecfr.gov/on/2018-03-06/titl ... tion-45.29

Aircraft Spruce sells vinyl numbers, but only 12" & 3",
i got my 2" numbers from Aerographics.

Thanks, I just shot them a email

Thought the 2” on an older plane only worked until the repaint then you had to go 3”?

The last owner put the N out on the rudder, 3”, I’d like to change the color to better match the trim and put it on low on vertical stab


Also seriously considering the aero classic 8.5x6 “tundra” tires if they can be mounted and legal on good year wheels

https://www.aircraftspruce.com/catalog/ ... -02501.php

Seems they also have a “heavy duty” solid tailwheel for the 2000

https://www.aircraftspruce.com/pages/lg ... idtire.php

Be nice to make it easier on the restored airframe on quasi bumpy grass and light dirt use, while not making it too hard for the little 65hp to pull through the air with what little it has for cruise speed

Does it have the cable actuated brakes, or hydraulic? The stock cable brakes aren’t good for much over stock sized tires. Having said that, the easiest route when I had my champ was getting the 26” Alaska Airstreaks. Great tire for the plane, but give up any hope of the brakes holding much more than for a run up , this is with the cable type brake.

7.00s are the largest size on the TC for a 7AC with Goodyears. Cleveland wheels allow the use of 8.00s on a 7AC.
See page 21 at the top of this document. (http://www.hangar9aeroworks.com/Aeronca ... /A-759.pdf)
Bigger sizes than this require additional paper.

The stock cable brakes will hold 6.00's during runup, but it takes a lot of brake pressure.

I'm running 6's on my 7AC with a solid Maule tailwheel, and it's fine for rough grass strips. It seems like lots of people run 8.50s with a magic free STC that I've never been able to get ahold of. I've never wanted to pay the weight penalty for the big tires either. With our 7AC with a C85 without electrics, I've got a useful load over 550 lbs, which I'm loathe to reduce.

On the Engine:

Assuming you are under a standard airworthiness certificate, converting an A65 to A75 is more than just the carb. It is articulated by Continental here: https://mooneymite.org/pdfs/ContSB.M47- ... 60supp.pdf

You would then need approval to install an A75 on a 7AC. The Type Certificate does not list any 7 series with an A-75 engine. I'm not sure on Aeronca Service letters, but I doubt it. The existence of STCs SA1679NM and SA1684NM suggests that the manufacturer's permission for the conversion may not exist. Bill Pancake is an expert on this stuff (tires and engines), and would know the answers off the top of his head. Give him a call.

Cable actuated Goodyear disks


Thanks for the tips

I’ll give pancake a call, I’ve read that name a few times


Thanks guys