View Full Version : Hand Propping

08-16-2004, 10:00 PM
How many hand-proppers are there in cyberland? I, for one, prefer sissy electric starting, but I'm curious how many of you are of the "manual" persuasion.

08-16-2004, 10:11 PM
Given a choice I prefer to start the plane from within. That said... There's a Champ out here with no electric I fly whenever I can. There's something about flying a plane with minimal equipment that is immensely satisfying. I've often wondered if I'm nimble enough to prop it on floats or skis.

08-16-2004, 10:17 PM

08-16-2004, 10:26 PM
We've always had J-3's around that I've always had to hand prop and I'm perfectly comfortable with it, you just have to be safe with it. I was taught to NEVER handle prop with the mind set that it wasn't going to start because the mags were off, ALWAYS treat it like its hot and could start anytime you move it. When pulling the prop through make sure you've got a good upright stance and swing where you're not leaning into the prop. When starting a J-3 by myself I always stand behind the prop seaplane style with my leg against the tire and my left hand ready to reach for the throttle or mag switch. This is all just what works for me.

Ursa Major
08-16-2004, 10:33 PM
I've done it when I had to, but it sure is nice to be able to turn the key and not have to worry about footing (when on ice or snow) or having the plane get away from you when it's on skis.

That little bitty Odyssey battery sure does a nice job of turning the prop and weighs a lot less than the old battery. But, if you really want to cut the aircraft weight down to a minimum for maximum performance, removing the electrical system, starter, wiring, and battery will probably knock off at least 50 lbs.

08-16-2004, 10:40 PM
Being of the weaker mind and leaving my master on every once in a while, I do it more often than I care to.

08-16-2004, 10:44 PM
I used to do it all the time on T-crafts and our Chief. Good advice to always treat it as if the mags are hot. Once I was careless and have a scar on my hand to remind me I screwed up. I was "slurping" engine moments before with my head close to the prop to hear the "slurping" so luckily I only have a scar on my hand and still have my head!!!

I still will prop a plane if needed, but then I learned my lesson the hard way.


08-16-2004, 11:59 PM

Marc Olson
08-17-2004, 12:46 AM
Once I got my rating, I learned to fly in a J-3 with no electrics. Float plane start between the prop and the throttle, even if I had someone in the front seat. I often flew alone... Even though I now fly an electric -12, the magic of flight, starting with the wood prop, nose tank with cork and finishing with the hand prop has a strong allure.

Only through negligence on my own have I never successfully hand-propped my -12. Tim Randall offered lessons that I've not found the time to accept, but I have been stranded through a broken alternator wire and nearly stranded (except for the spare battery carried at all times) due to poor Master Switch management.

Seems a skill well worth learning.

08-17-2004, 06:17 AM
Probably already mentally noted by all the wise pilots here but I'll say it anyway. My O 235 starts 1 blade on impulse couplings. Knowing exactly how your O 320 starts with a starter is important and can make for an easy hand prob start should the need arise. How much prime at what temperature is also very important. With fuel injection an engine will start faster because the fuel is in all cylinders measured through a fuel meter. We have the same option available to us but many engines don't have all there primer lines connected for one reason or another. This can lead to a more difficult hand start. My point is to get the electric start procedure down to a science and apply the same procedure to hand prop. With a carb,after priming it helps to pull the prop through a few times with the mags off to sort of balance the fuel to air ratio out. Than one prop and pop. Can anybody add to this rational?

Cajun Joe
08-17-2004, 06:18 AM
"Our enemies are innovative and resourceful, and so are we," Bush said. "They never stop thinking about new ways to harm our country and our people, and neither do we.".

Hey Diggie,
What ... is this SCOrg or CNN?

08-17-2004, 10:02 AM
I can attest to TJ's DC-3 starting technique (rope/pickup). I've never done it but have seen it done. When stuck, it's time to innovate, and pilots are amazingly resourceful regardless of the airplanes they fly. There's also the buddy start. P-3's, Hercs, etc., jump-start each other using prop-wash alone. And suck-and-blow flying machines like B-737's hook up to a shared air hose. Yes, there was (and is) flying before starters, APU's and automation. And, if all else fails, there's always the cell phone that makes the starter button work: It will get you going, but it's nowhere near as much fun.

08-17-2004, 10:28 AM

08-17-2004, 10:47 AM
Diggler, I liked your sign-off, too. It was a real classic!


Cajun Joe
08-17-2004, 11:10 AM
Sorry Dig,
I was just being overly sensitive. And now we've got Anne cranked. We did manage to hold her back for the entire N'Olstein week.

08-17-2004, 11:12 AM
Only 'cause I was outnumbered! And flying and talking cub with you guys was way more fun than arguing politics. Thanks for a great week!


Cajun Joe
08-17-2004, 11:13 AM
And Anne,
We enjoyed the morning showers with you.

Marc Olson
08-17-2004, 01:42 PM

Good observations, and certaintly the approach that I used with the J-3. I've started following the same procedure every time when starting cold, and I get mixed results on how long I crank before firing.

Even with the starter my O-320 can be finicky to start, usually for me when in the field and never for my mechanic when it's in my hangar. Go figure. I *sometimes* start on one blade, sometimes the starter only engages for half a blade and then stalls as though under high resistance.

I've been focused on troubleshooting a hot engine, which I think we've solved, so the next project is reliable starting. While doing a compression test this morning we noticed that the impulse coupling was failing to couple 1 out of every 4 blades. That and potentially a flat spot on the starter are what we're going to look into.


Alex Clark
08-17-2004, 01:49 PM
I wrote up a float training manual for my J3C/PA-11-90 hybrid.
(70 pages)
Anyway I put in a section about hand-propping since that is the only way to start the little cub.

Of course I wrote disclaimers all over the place.

One trick when on floats or out in the boondocks (on wheels) while hand propping is to pull out the mixture to cut off after you prime the engine. That way it won't go very far if it takes off on you. It will still run long enough to get your hands back inside to run the mix and the throttle.

That way if you fall off the floats during a roaring start-up, you won't have as far to swim.

08-17-2004, 02:44 PM

Even with the starter my O-320 can be finicky to start, usually for me when in the field and never for my mechanic when it's in my hangar. Go figure. I *sometimes* start on one blade, sometimes the starter only engages for half a blade and then stalls as though under high resistance.

Have you checked if your mag switch is cutting out the right mag in the start position? It could be firing early if you only have one impulse.

Starting on the left mag only is still used hand propping

08-17-2004, 04:15 PM
I have to hand prop my O235-C1 because of no electrical system. Diggler
says he has to open the throttle 1" to 1 1/2 " to start his 160hp. If I did that
my Cub would run over me! Yes, the throttle travel is nearly the length of the slot. Anyway, one point to remember is: IF IT DOESN'T START EASILY,
TIE IT DOWN! Jiggling the throttle and switching the mags on and off while you clear the engine will bite you eventually. I'm certain this has been said


08-17-2004, 09:23 PM

08-17-2004, 09:47 PM
good advise Mark and 46... You two do know how do do it!

Marc Olson
08-18-2004, 12:02 AM

Thanks for the tips. As it would turn out, for the five starts I did today, only the first (with my mechanic standing next to the plane) showed any hesitation at all. The others showed the starter freewheeling the prop like it was hooked up to Hoover Dam instead of just the little ol' oddessy battery at the firewall.

The impulse coupling is now on the ever present squawk sheet...


08-18-2004, 05:29 AM

The whole impulse thing brings up a point dicussed many times. My 94 super 18's owners manual clearly stated to start on BOTH mags. I would assume this means all starting procedures. The impluse snaps on every cylinder but if there is no prime in that cylinder hand proping will take longer. Everybody should,for more reasons than hand proping make sure that all cylinder priming lines are inplace. Over time they get broke and capped off. And remember they are a piper part not a Lycoming part.
Anyway,I have noticed that hot 320 is a little trickier when hot to start.
Back to impusle mags. Do the older owners manuals for supercubs with 320's instruct to start on just one mag? I know in theory the early spark could hurt but I can't remember ever having a back kick from any plane.
Is one mag safer on a hand prop start as a matter of general procedure? I heard about a doctor at a flyin in florida loosing a hand prop starting his plane 3 or 4 months ago. Anybody else hear this?

08-18-2004, 09:20 AM

SuperCub MD
08-18-2004, 04:10 PM
320's hand prop easy.

Cold start-
Reach inside and set the parking brakes.
Pump the throttle twice, back to idle, then just cracked a little.
Mags off, pull the engine through two blades to get the fuel in the cylinders.
Left mag on, and it should start on the first blade.

Hot start-
On shut down, let it cool as much as possible, then shut down by pulling the mixture, mags off when the prop stops, leave the mixture out.
To restart, set the parking brakes.
Leave the mixture out, and turn on the left mag.
Pull it through one blade, it usually sputters on fumes long enough for you to reach inside and shove the mixture in.

If you screw up and flood it, mags off, and pull it through backwards 10 blades, then do the hot start again.

Along with the electrics, I take off the priming system too...just dead weight and a lot of lines to constantly repair, (as long as your carb has a accelerator pump).

The thing with hand proping is just to always remember to keep your **** together when doing it. This is not the time to be thinking about your taxes, what you will have for supper, the legs on the waitress in the restaurant, ect... Make a consious effort to put all your focus on the task at hand while you are doing it.

Always prop a Cub from behind. Lock your left hand on the door frame and don't let go for anything.

If you have dual impulse mags, start on both instead of left.

08-18-2004, 06:15 PM

The only problem with using the "pump the throttle a couple times" to prime an engine (and I've done it my own self many times, so don't get testy) is that most of that fuel from the accelerator pump will simply drop to the bottom of the air box. If you are unfortunate to get a back fire (and it does happen) you can light your little friend on fire, and maybe even your own self.

Primers and lines can be a maintenance pain, but they do serve a purpose.

One essential item for hand propping is to have a halon fire extinguisher handy (as in HANDY, not in the baggage compt) in case. Remember that the admonition in engine manufacturer's manuals for an induction fire goes something like: "continue to crank the engine with the starter to suck the flames into the engine". Hard to do by hand, at least fast enough to make any real difference.

I thoroughly agree with all your other points. Keeping one's head in the game is absolutely essential when doing the old Armstrong starter technique.

And, as noted here several times DO NOT stand out front to hand prop--ALWAYS prop from behind the plane, it gives you something to grab if you lose your balance, and you are out of the way of the meat grinder if things get sporty.


SuperCub MD
08-18-2004, 07:30 PM
Damn it MTV, I was going to mention the Halon extinguisher that you should ALWAYS have in case of carb fire when proping out in the sticks, but I thought that was just obvious, and I was sick of typing..... :wink: Good point though, being in the middle of nowhere watching your Cub burn to the ground would just suck.

I went through the primer vs pump thing, and actually, the primer nozzles just shoot the fuel a little higher in the intake. If you have ever watched one work, it shoots the fuel across the intake port, where it drips back down through the carb anyway. Most primer nozzles don't get cleaned often, and are no better than squirt guns. The accelerator pump usually does a better job of atomizing the fuel. Using a primer instead of the accelerator pump is just a false sense of anti-fire security, not unlike removing header tanks...if you know what I mean...

I've put out my share of carb fires on the ramp over the years, all have been set ablaze by idiots with primers that didn't know what they were doing. If you hand prop, you get to know your engine in a very intimate way, and you soon learn exactly how to start it best.

08-18-2004, 11:49 PM

Can't disagree with any of that, except that the primers are a LOOONG ways further up the induction than the accelerator pump.

As you note, though, get to know your airplane by propping it, and none of this will be an issue, cause you'll figure it out.

I watched a very nice Beaver burn to the ground once, by a Goose pilot. In the Goose, you boost the throttles, cause there isn't any primer, and the induction is a bit different. On the Beaver, you always prime it, cause there is a very good chance of an induction fire in them.

So, a little paranoid about the use of accelerator pumps to start, though, as I noted, I've done it many times my self.

Just be careful out there. They can burn.


08-19-2004, 12:52 AM
Hi Mike

I used to start Beavers by the book with prime and still do with cold engines. I was spooked by an induction fire I saw. Came to find out that if you give a couple of accelerator pumps (warm) and then put your seatbelts on-close the door-etc, etc, etc... and then turn it over (mags off initially)you won't get that backfire. If you pump and turn immediately that is quite a different story. Something about a round engine!


08-19-2004, 10:00 AM
My O-360 starts a lot better using the accelorator pump verses the primer. I've always done three shots of the primer on the previous O-320 then start. But the new O-360 in my 18 won't have it. Two pumps of the throttle and it fires right up. My O-320 in the 14 likes the primer. I think all engines start a little different. Crash

08-19-2004, 10:15 AM
I've always started carbureted engines with the accelerator pump. KOldham from this site convinced me to engage the starter at the same time I pump the throttle to start a draft, as opposed to pumping throttle (allowing fuel to puddle) then engaging the starter. That made sense, and that's now what I do.

08-19-2004, 10:25 AM

You must have REALLY long arms if you can work the throttle and hand prop your plane at the same time!! :o :o

John Scott

08-19-2004, 10:35 AM
I was a little off-topic, but everybody else has been, so what the hell.

I have been accused of being a knuckle-dragging neanderthal, but what does my wife know?


SuperCub MD
08-19-2004, 06:22 PM
Notice I did say to pull a few blades with the mags off after priming to get the fuel up into the cylinders....that is a important step no matter how you prime.

Geez, you Alaska boys put starters on Beavers as easy as a 985 hand props???..such cushy lives you lead.... :wink: They do hand prop easy, I'm sure you guys have done it from time to time too. I usually get round motors spinning with the starter, mags off while priming for about a five blade count, off the prime and throw the mags on while still spinning and tickle it with the booster till it lights off, a slight push on the throttle to keep things motivated if needed. There is no prettier sounds than a big round engine coughing to life, shattering the early morning silence. Always puts a little smile on your face no matter how bleary eyed and tired you are.

08-19-2004, 07:20 PM

Interesting comment re: the O-360 starts. I routinely use three strokes of prime on the 360's and they fire right up, even better than using the accelerator pump.

Your comment about every installation being different is really true, though.

Found that out in a Cub on Kodiak, which I ran for many hours, with no signs of carb ice except in really severe conditions. Put a brand new engine on it, and the thing made carb ice like crazy. Got my attention a few times at first, till I figured it out.

Gotta love em.

And, Supercub MD, yep, you got that all right. Used to start 600 Ag Cats by hand, and done right it's a piece of cake.

The tourists really don't like to see their pilot outside mucking about with the propeller as they bob down a river, though, so as you say, we wimped out and put starters on the Beavers. Don't forget that there are different systems on the 985's too, though.

And, I still daydream about firing up that 985 on a cool Kodiak morning, hearing the first five fire, then the next couple coming on line, and then the rest, all enveloped in a little cloud of smoke. What a great sound.