Hand Proping C-65

I'm not sure whether to post this in here or in the maintained thread, so if the community thinks of a better place to put this post, please move it.

I'm currently giving instruction in a Aeronca 11AC Chief that has no electrical system and a C-65 that's been upgraded to 75 hp. I've got a lot of experience hand propping, but most of it is on the Lycoming 0-290 and 0-320, so I have some questions.

The C-65 as I said has been rebuild recently (about 50 hrs ago) and upgraded to 75 hp. It also has a primer and the old style "shoe box" mags with no shower of sparks or impulse coupling.

My normal cold starting procedure has been:
1 shot of primer
Throttle closed
Pull the prop through 2 times, mags cold
Contact

And it USUALLY starts on the 3rd or 4th blade. More about the usually later.
With the throttle closed, the engine idles around 500-600 rpm.

Question 1.)
What is a good cold start procedure for this engine?

Hot start:
No prime
Throttle Half
Contact
As soon as it fires, 800 to 1000 rpm (requires two people for sure)

This usually takes a while, but everything else I've tried usually floods the engine.

Question 2.)
What is a good hot start procedure for this engine and what do you consider a "hot start."

This morning when I tried the cold start, the engine acted like it was flooded on the 2nd or 3rd pull with the mags on, so I went to half throttle. After a few more pulls, a lot of gas started coming out of the carb, and we had a nice puddle under the cowl. Much more than I've ever seen come out of the airplane before. We tried starting it assuming it was flooded. It caught a couple times but would only run for 30 seconds or so before the engine would just quit. (Yes, the gas was on. First thing I checked.) We let it sit for 15 min, and tried again assuming it was flooded with the same result. I called it quits and assumed there was something wrong with the airplane because 1.) I had never seen that much gas under the cowl even when I've really flooded it before, and 2.) The engine wouldn't keep running after it fired which has never happened before. Someone else came out a couple hours later, and it fired up on the 3rd pull and it ran like a clock.
Obviously I did something wrong, but I have no idea what. Any help will be greatly appreciated. What should I have done differently?

Also, this engine has a tendency to kick back a lot. (A result of the timing being incredibly advanced with no impulse coupling) If it does that more than once, I assume that the engine is flooded, but this doesn't seem to work all the great for me, so any advice on what to do after the engine kicks back once will also be helpful.

I love these old airplanes and most of the quirks that go along with them, but I would really like to reliably start them. After about 40 starts on this engine, I still don't have it figured out, so its time to ask the experts.

Thank you!

If you have a lot of fuel leaking out you may have a stuck carb float, (open) which floods the carb. Try turning off the fuel and tapping on the side of the float bowl, and then turn the fuel back on and see if it leaks. Also could be a loose or cracked fitting or hose.

I hand prop the C-90 in my J3 Cub. FIRST TIE THE TAIL DOWN! I don't care who you have sitting in the cockpit, a tie down is safer. Chocks are fine, but as a second item.
Next, I give one shot of prime, might do two if it is real cold. Don't pull the prop through, that wastes the prime. Just barely crack the throttle and if you ignored the part about tieing down, I would emphasize the barely. Then contact, mags on and prop. Mine will start almost all the time on the first pull, if not the 2nd, but mine does have the shower of sparks mags I think, and you can hear the impulse coupling click if you pull the prop through slowly with the mags off.

I woud never go to half throttle or anywhere more than just open unless I am in the plane. Once mine starts, it will idle about 800-900 with just that slight amount of throttle, enough to want to creep. I close the throttle and it will then idle about 500 and sit still so I can untie the tail and pull the chock.

Mine is harder to start when the engine is warm, I think I skip the prime, can't recall for sure.
Be dam careful, as they say a Cub or a Champ can just barely kill you.

We always tie the tail. I like backups. I've never had to hot start it on my own, and I'm not sure what I would do in that situation, but I definitely would not use half throttle. That's only something that we do when we have someone in the cockpit.

Thanks for your input, but shower of sparks definitely makes things easier. I know for a fact that the mags do NOT have shower of sparks or an impulse coupling. It doesn't click when pulled through.

Thanks!

One thing I thought of about your problem of kicking back. Try pulling it through just one time with the mags off, after you have primed it one stroke. Then mags hot and prop it. That may help, may not.
I hope you have a wooden prop, seems safer and more comfortable.

Quote:

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Originally Posted by svanhatt

Question 1.)
What is a good cold start procedure for this engine?

Question 2.)
What is a good hot start procedure for this engine and what do you consider a "hot start."

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Stromberg carburetor with back suction mixture? And if so, does it still have a SS needle valve?

All good ideas. When I had my Champ and Luscombe, I usually was alone when I hand propped. Instead of tying the tail, I used one of my tie downs and looped through what ever was available. Usually a tiedown point. I closed the loop to a seat belt or the fuselage strut attachment. After start, I got in the seat, untied and pulled the rope free and tossed it in the baggage. Yes, its lazy but I didn't need to leave the cockpit area with a running engine.

Another thing that I always did was after the priming, etc and before contact, I turned the fuel valve off. In case everything went wrong, the engine would stop after a minute. If everything went OK, I was back at the cockpit door and turned it back on.

I did not like the "sea plane method" because it called for wrapping fingers over the trailing edge of the prop. You could lose fingers in a kick back.

Bob

Man - that's great idea - turning the fuel off and then back on when you're in the driver's seat!

I guess each and every engine has its own pecularities. My Continental A65 starts best with three shots of prime, eight blades and one pull starts it. On hot starts??? Depends on how long it has set since running. I start by trying no prime, five blades and contact. If that doesn't work after three tries - one shot of prime and contact. Usually starts. A lot better than the Lycoming O145 that it replaced. I've cranked that mother as long as 45 minutes with no joy.:(

Hand propping with a completely closed throttle will help flash any liquid gas in the intake manifold to vapor, which is necessary for ignition. The high velocity of air past the closed throttle plate will also draw atomized fuel into the engine. Go easy on prime as it tends to cause kickbacks. It is much easier to get a restart from a starved-out engine (i. e. too lean) than from a flooded-out engine.

Quote:

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Originally Posted by svanhatt

I know for a fact that the mags do NOT have shower of sparks or an impulse coupling. It doesn't click when pulled through.

Thanks!

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You should have an impulse on at least one or both magnetos, perhaps the impulse is sticking or something when you cannot hear it.
What do you have, if not an impulse?

Quote:

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Originally Posted by Bill Berson

You should have an impulse on at least one or both magnetos, perhaps the impulse is sticking or something when you cannot hear it.
What do you have, if not an impulse?

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Many older magnitos did not have impulse. They depended on moving the blade fast enough to generate the spark that the impulse mechanism generates by "snapping" the rotation at the proper time. That's why you see all the leg swinging gyrations - not necessary with impulse equipped mags...

I agree with what everyone else here is saying. I have an A65 on my Taylorcraft. I use my HOT START procedure anytime my engine has run long enough to get up to operating temperature within the last hour in winter and four hours in summer. My summer time normal start procedure is secure the airplane, pull prop through 6-8 blades (my way of priming), fuel OFF, throttle FULLY closed, mags hot, and prop it. If the engine has run within the last hour (four hours in winter), I don't use any prime and crack the throttle 1/8". If I mess up and start seeing fuel leaking, usually about one drip per second for 10-20 seconds, I turn the fuel off, mags off, throttle cracked 1/8", and turn the prop backwards 10-20 blades-depending on how much fuel was leaking. I have learned to keep an eye out for the fuel leaking and have been able to avoid major flooding incidents. After pulling the prop through backwards I usually let it set a couple minutes, then revert to the appropriate start procedure for the outside temperature. In the winter I use the same procedure as summer, but pull the prop through more blades for more prime (10-12 for 50 to 60 degrees--up to 16 or 18 blades if it is down in the 20s or 30s.

It does sound like you may have had a stuck needle. There are three different needles that have been used on the Stromberg carb, steel, delrin, and steel with a rubber tip. If yours is delrin or rubber tipped, it could be worn out. Or your float could have taken on some gas and not be floating properly. Bill's idea of lightly tapping on the side of the carb would jar loose anything that might have gotten stuck in the needle, or if the float was just cockeyed and stuck. If it keeps flooding you may need to take the carb apart to investigate the function of the float, needle, or just adjust the level. You don't need to take the carb off to do this.

It would well be worth the trouble to get another mag with an impulse coupler for at least one of the mags. Don't trade your shoe box mags in on a new Slick unit. You can find another used mag on Ebay or Barnstormers and either keep your shoe box as a spare or sell it.

Good luck,

Each engine, even two of the same identical configuration, has its own peculiarities and best starting combination. It's been some years so I don't recall the particular sequence for the A-65 in my old T-Craft, but it usually started on the first or second pull after turning the switch on (if cold). I do remember that it liked to be pulled slow. Hot, it could be a bitch to start. I had the Bendix shoebox mags with no impulse, and the Stromberg carb with no mixture control or air filter, just the brass heat box.

My girlfriend also had a T-Craft with an A-65, and it started completely differently.

If you know you're going to need to restart the engine very soon after shut down (hot start), open the throttle fully after you shut the mag switch off. Letting the prop spin down with the throttle open will clear the fuel, and will help prevent flooding when you re-start it. **Be sure to return to idle position after the prop has stopped.** I assume your carb does not have an accelerator pump. If it does, then don't bother with this.

I have a Aeronca Chief, the mags are now Slicks with dual impulse. Cold starts (30 deg. F) 3 shots of prime, (45 deg. F) 2 shots of prime, warm up to about 4 hours since last run - no prime, mags and fuel off, throttle closed, pull 8 blades, set throttle and turn on mags always starts first pull. I would like to recommend another safety option not mentioned, I made a throttle stop that clips in place that will not let the engine operate above 700 RPM. I use this throttle stop every time I start hot or cold along with the fuel valve in the closed position. I know from experience that the engine will idle just long enough to pull the right wheel chock, get seated and retrieve the left wheel chock if you forget to open the fuel valve. With the use of the throttle stop I am comfortable using only the wheel chocks for engine starts (hard surface). I purchased the "Pilot Buddy" (13-04259, $32.50) from Aircraft Spruce as an alternate method to anchor and release the aircraft tail.

I would always leave the fuel valve off when hand propping. At 1500 RPM the bowl would run dry in 30 seconds. That's all the longer you'd have hold back the airplane. Hot starts-- I would often fully open the throttle (mags off) and pull the prop backwards about 5 times. And then CLOSE the THROTTLE, turn on mags and hand prop normal. Worked 90% of time.

The engine should have an impulse coupling. That will cure the backfire problem pretty well, and it should start on the first or second pull. Even the old Eisemann mags used with the balltop plugs had an impulse coupling.

Ever since line boys are no longer allowed to give you a prop ... yeah, I am that old ... I have added a cheap glider tow hitch to the tailwheel spring. I just tie a loop in a tie down rope and catch it in the tow hitch. When it starts and I am ready to go, I just reach down and pull the tow release. No pain, no strain, no caught fingers or long dangling ropes.