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Thread: Hand Propping

  1. #1

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    Hand Propping

    Well, it finally happened! 100-miles from the nearest human and I had a dead battery (left master on - will I never learn?) and a defective Earth-X jump pack (those fuses blow so easily!).

    On floats now. My arms are not long enough to hold onto the doorframe with my left and crank with my right. Not much to hang onto otherwise. My balance is nowhere near good enough to use my two arms/hands on the prop. I would have ended up in the drink - or worse.

    Anyway, thanks to the liberal use of many four-letter words, I managed to start the beast (O-320-160) but it wasn't easy. Left mag only seems to be the best method. I was worried that I would over-prime the engine so I didn't use the primer, just a couple of shots of full throttle seemed to be enough (50 degrees F.)

    I found that getting the prop past the "bounce" of the compression stroke is the hard part.

    It's a very satisfying exercise when it finally kicks off and you know you're homeward-bound. This is actually the first time in over twenty years that I've had to put theory into practice.

    I'm looking for any useful tips on hand-bombing that might help me if there's a "next time".

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    80 years old, and no problem hand-propping a 180 Wip Cub. Are you sure your prop is indexed properly?
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    cubdriver2's Avatar
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    Tie a loop of line to your seat base for you to hold onto. Not just for balance, left handhold is also your safety hold in case floats bottom out after start and stop your momentum from throwing you into prop

    Glenn
    "Optimism is going after Moby Dick in a rowboat and taking the tartar sauce with you!"
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    I'll avoid the hand-propping question, because I have never done it and I'm not qualified. But if you are going to be 100 miles from any other human solo in the future, you probably need to invest in a sat phone. Medical problems, trauma and all sorts of mechanical issues can happen out there. The peace of mind will be worth it because it will enhance your confidence in your own safety once you are at your destination.
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  5. #5
    stewartb's Avatar
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    Even with a starter every pilot needs to know what the prime routine is that allows the easiest starts. With proper prime I pull the prop through several rotations with mags off to distribute the fuel. Then it usually starts on the first or second pull. The pull doesn't need to be an athletic move. Just pull the prop through the compression stroke and get your hand out of the way. Very little effort is required.
    Last edited by stewartb; 08-31-2021 at 01:21 PM.
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  6. #6

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    Quote Originally Posted by Tennessee View Post
    I'll avoid the hand-propping question, because I have never done it and I'm not qualified. But if you are going to be 100 miles from any other human solo in the future, you probably need to invest in a sat phone. Medical problems, trauma and all sorts of mechanical issues can happen out there. The peace of mind will be worth it because it will enhance your confidence in your own safety once you are at your destination.
    I had a sat 'phone but gave it up due to cost. My Inreach will summon help but, as with a sat 'phone, that help would probably not arrive in time to save a life in the case of a heart attack or serious accident. A minor injury we can deal with in the field and I can fly home. As for a mechanical problem, the cost of chartering in a mechanic would likely be half the value of the airplane. These are the realities of flying in "the bush" that we accept in exchange for seeing and doing things that few others can experience.

    Now that I know it can be done, and thanks to the tips already posted, I have some confidence that, even at my age (73) I can 'git 'er done.
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  7. #7

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    Quote Originally Posted by bob turner View Post
    80 years old, and no problem hand-propping a 180 Wip Cub. Are you sure your prop is indexed properly?
    Yes, the prop is properly indexed. On the "un-helpful" side, it's a "tight" engine with oil pressure in the 90 psi range and the compressions of 78 or 79/80. On the plus side it's nicely tuned with timing spot-on.

    I like the comment by stewartb: perhaps I was trying too hard.

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    Quote Originally Posted by stewartb View Post
    Even with a starter every pilot needs to know what the prime routine is that allows the easiest starts. With proper prime I pull the prop through several rotations with mags off to distribute the fuel. Then it usually starts on the first or second pull. The pull doesn't need to be an athletic move. Just pull the prop through the compression stroke and get your hand out of the way. Very little effort is required.
    x2 on what Stewart said. People make hand-propping into a big deal when it really is a non-event. Cold engine, couple pumps with primer, mags off, turn over 2 or 3 blades, mags on, 1st or sevond blade usually starts. Warm engine, barely crack the throttle, mags on, usually starts in 2 or 3 blades.
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    akavidflyer's Avatar
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    I learned the hard way that the earth ex jump pack is a POS. My $89 amazon special has more capacity and way more "omph" to start stubborn engines. I know of a few other earth ex jump packs that have left people stranded as well.
    Before ya crucify me for bad mouthing earth ex, I have a few of them in my plane and other toys and I love the battery, but the jump pack sucks and will barely start my lawn mower once before its dead.
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  10. #10
    mvivion's Avatar
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    Good information so far on the subject. What's missing so far is: What's the condition of the engine? Is it a warm engine, as in shut down in the last hour or so, or is it a stone cold, ambient temperature engine?

    With Lycomings, and most other carbureted engines, it's REALLY, REALLY easy to flood a warm engine. So, with a warm engine, if I'm hand propping, I set the throttle just off idle, as in cracked a half inch to three quarters of inch, mixture rich, and start it. NO PRIMING a warm engine.

    Cold engine procedure: I ALWAYS use the primer to prime a cold engine, rather than rapid strokes of the throttle. The manufacturer offered primer for a reason....to start a cold engine. It puts the fuel into the cylinder....that's where the magic occurs, after all.

    Pumping the throttle (on many engines, but not all) actuates the accelerator pump, which squirts raw fuel into the carburetor mouth. These engines have updraft carburetors, which means that fuel then has to be sucked up, through the induction system (the carb, and those big tubes on the side of the engine, to get to the cylinder....where the magic happens. SOME of that fuel can drop down into the air box. In the remote possibility that you incur a back fire.....you may in fact induce an induction fire. And, without a starter to crank and suck that fire into the engine.....you may be now truly SOL.

    So, the ONLY time I use an accelerator pump to start an engine is IF I can crank the engine through first, and pump the throttle AS I'm cranking it over.

    I was taught all this when I was flying Beavers for a living.....taught to me by a crusty old time mechanic, and Beaver pilot. Not long after this, I watched a guy burn a beautiful Beech Model 17 to the ground when he pumped the throttle FIRST, then cranked.

    Granted the R-985 is much more inclined to backfire, than an O-320, but I've seen carburetor fires in O-320s too. Those ended well, because the pilot kept cranking to suck the fire into the engine, where it belongs.

    Sorry this is so long, but frankly, one of the things I see most frequently as a flight instructor is that most pilots have no idea how to safely and properly start their engine.

    As to hanging on, I often use the back of the side cowl to hang onto while propping. Worst case scenario (Husky, which doesn't have a gap on the side of the cowl), I just prop my left hand firmly against the side or top of the cowling, move far enough forward to reach the prop, and start.

    I highly recommend that EVERYone get some good instruction in how to hand prop your airplane engine. And, by the way, that's the way you should be starting it every time, even with the starter.....just sayin.....

    MTV
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    wireweinie's Avatar
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    Quote Originally Posted by bob turner View Post
    Are you sure your prop is indexed properly?
    Amen to that. If a prop is indexed 'by the book' the mag will snap with the prop approaching 6 o clock. If you back the prop up one bolt hole, the mag will snap closer to the 3 or 4 o clock position. More comfortable and safer.

    Web
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    Quote Originally Posted by wireweinie View Post
    Amen to that. If a prop is indexed 'by the book' the mag will snap with the prop approaching 6 o clock. If you back the prop up one bolt hole, the mag will snap closer to the 3 or 4 o clock position. More comfortable and safer.

    Web
    I like props indexed so that the prop is in “proper position” to hand prop. Which is , facing forward, the blades are at 2 and 8, approximately.

    At one point, Aviat changed indexing to 12/6, which makes it near impossible to prop on floats, and much more difficult on wheels. I called and asked about it, and they responded that Lycoming told them there was very slightly (their words) less vibration with those engines indexed at 12/6.

    I told maintenance that I could live with a bit more vibration, but I really didn’t care to sleep out at -40 again, thank you.

    I did prop one with the prop indexed at 12/6 with the plane on straight skis. It was a bitch….nuff said.

    MTV
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    Quote Originally Posted by akavidflyer View Post
    I learned the hard way that the earth ex jump pack is a POS. My $89 amazon special has more capacity and way more "omph" to start stubborn engines. I know of a few other earth ex jump packs that have left people stranded as well.
    Before ya crucify me for bad mouthing earth ex, I have a few of them in my plane and other toys and I love the battery, but the jump pack sucks and will barely start my lawn mower once before its dead.
    I'm a fan of Earth-X but I agree that the Jump Pack needs some design changes. For one thing, the fuse (fusible link) is enclosed in such a way that you can't get at it without destroying the fuse holder. They need an openable fuse holder with a bolt-in link that can be replaced and made available by Earth-X. One would think that, in blowing the fuse, there would be an obvious spark. But my fuse blew (apparently) just by the starting current required.

    Edit: You would have to admit, though, that their customer service is second-to-none. They are sending me a new set of cables for the Jump Pack - gratis!
    Last edited by NunavutPA-12; 09-02-2021 at 08:18 PM.

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    Quote Originally Posted by mvivion View Post

    So, the ONLY time I use an accelerator pump to start an engine is IF I can crank the engine through first, and pump the throttle AS I'm cranking it over.
    I can't remember the last time I used a primer to start a Lycoming. My PA-28 O-360 sometimes sits a month without being flown. It almost always start in less than 2 seconds of cranking with a couple of cycles of the throttle lever.

    Within earshot of my hangar is flight school also using PA-28. They grind on the starters for 10 -20 seconds and have no clue how to start the engine.

    I agree that the throttle pump is useless for a hand start but I would have to be in dire straights to want to do that anyway. Not that I'm afraid of propping an engine - J3 time and an Aeronca 11BC past owner.

    FX-3 is injected and electronic ignition. It's still a very tight engine and I don't think I could prop it. I carry a lithium battery pack and hope to never need it.

    Only 5 hours on floats in a PA-18 and no way I would try to prop that. If it started I'd probably be in the water watching it float away. One day I hope to get some more SES time so I have more that a trophy rating.

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    mvivion's Avatar
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    Quote Originally Posted by frequent_flyer View Post
    I can't remember the last time I used a primer to start a Lycoming. My PA-28 O-360 sometimes sits a month without being flown. It almost always start in less than 2 seconds of cranking with a couple of cycles of the throttle lever.

    Within earshot of my hangar is flight school also using PA-28. They grind on the starters for 10 -20 seconds and have no clue how to start the engine.

    I agree that the throttle pump is useless for a hand start but I would have to be in dire straights to want to do that anyway. Not that I'm afraid of propping an engine - J3 time and an Aeronca 11BC past owner.

    FX-3 is injected and electronic ignition. It's still a very tight engine and I don't think I could prop it. I carry a lithium battery pack and hope to never need it.

    Only 5 hours on floats in a PA-18 and no way I would try to prop that. If it started I'd probably be in the water watching it float away. One day I hope to get some more SES time so I have more that a trophy rating.
    As I said, there’s LESS risk to stroking the throttle WHILE cranking.

    But, here’s a simple question for you: why do you suppose there’s a primer on most carbureted engines, and on some injected ones? Do think that is some sort of “gizmo” that Lycoming just installed cause they could?

    I use the primer because that’s the way the designer of the airplane might have thought was best.

    My first plane was a 90 hp J-3 on EDO 1320 floats. No starter, no electrics, no such thing as GPS. Prime that engine three strokes, reach out and shed start first or second blade every time. I have learned to hand prop every plane I’ve flown regularly, including Cessnas with IO-520 and 550.

    I have HAD to hand prop about a fourth to a third of those planes….or sleep out in some bug infested swamp.

    I do agree that a jump pack is a great alternative. So, here’s the next question: Have you ever TRIED starting that engine with the jump pack, so you know how it works?

    Start your engine however you like, but the primer is there for a reason. And the accelerator pump in that carb was NOT installed to help you start the engine.

    And, yes, the 185/206 I flew had primers, it was an option on those planes. For when your battery is dead and you have no electric prime. Used only in extreme cold, or if I screwed up.

    MTV
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    Garmin InReach Mini is the way to go instead of sat phone…
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    stewartb's Avatar
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    Anyone who’s lived with a big bore carbureted Continental for a winter or 30 knows the value of a primer and learns very quickly how to apply it.

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    You see a lot of people on YouTube bounce the prop against the compression, then grab it for a big push. Don’t do that. Bounce a little harder and it might go all the way through, fire, and injure you.

    It isn’t possible on floats, but I was taught that it was safer to prop from the front, pressing against the surface of the prop, not the edge. That preserves your fingers in case of a backfire.

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    I landed on a small gravel bar about a month ago and scouted around a bit and same issue. Couldn't seem swing the ground adjustable Sensenich enough to get more than one blade. Called a friend who drove as far down an oil lease road with a jump pack. After hiking 5 miles each way to get it I got it started right away. My 500 hr inspection was due on my mags so I did it when I got back to the airport along with cleaning and gapping my plugs. Found the distributer finger loose on the gear on a mag not in the serial number for that service bulletin. Started f=great after replacing the gear. A few weeks later the same thing. Waited with cowl opened and let the engine cool and it started fine after cooling. Load tested the battery when I got back and it was weak. New battery and no issues and I can tell it spins over better. I have found that 2 shots of primer instead on the throttle pumps and she starts after a few blades.
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    Quote Originally Posted by mvivion View Post
    But, here’s a simple question for you: why do you suppose there’s a primer on most carbureted engines, and on some injected ones? Do think that is some sort of “gizmo” that Lycoming just installed cause they could?
    I have a starting technique that works well with my engine in the range of temperatures experienced where I operate my PA-28. In much colder conditions I'd probably use the primer and be glad it was there.

    Let me ask you a simple question - Why would I abandon a starting technique that has worked well for many years with this engine?

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    Trying to refine my technique. These comments have been helpful.

    I was trying to "throw" the prop through the compression stroke. Now I understand (I think) that all I have to do is bring the prop to the compression stroke and then just pull it through as forcefully as I can. Correct?

    And I'll use the primer!

    I may even install a handle on the cowling to hang onto.

  22. #22
    mvivion's Avatar
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    Quote Originally Posted by frequent_flyer View Post
    I have a starting technique that works well with my engine in the range of temperatures experienced where I operate my PA-28. In much colder conditions I'd probably use the primer and be glad it was there.

    Let me ask you a simple question - Why would I abandon a starting technique that has worked well for many years with this engine?
    A simple answer, in the form of a question: How does your Pilot Operating Handbook say to start that engine? I don’t have a PA-28 POH handy, but I’m guessing that resource, created by the manufacturer of that airplane suggests you use the primer. Does it specifically state that it’s SAFE to pump the throttle to start the engine?

    A simpler answer: Because there is a risk, albeit perhaps not a GREAT risk, of creating an induction fire by pumping the throttle to start one of these engines.

    In my experience, the highly qualified test pilots who flew certification test on that airplane and the engine manufacturer were the source of that POH recommendation for starting. Why would you do anything else?

    There may be circumstances and aircraft where that technique MAY be recommended by the manufacturer.

    For seven years I ran a college flight training program. We operated PA-28 and PA-28R aircraft, and later C-172. I can’t tell you the number of times I had to go start an Arrow because neither student nor CFI could start it. First thing I’d do: Take out the POH, turn to page for flooded start, cause by the time I got there, the engine would be flooded. Follow the guidance, and voila!

    On flooding: If you’re going to hand prop an engine DO NOT flood it! As I noted earlier, is hard to flood a cold engine but REALLY easy to flood a warm one. If that engine (carbureted 4 cylinder Lyc.) is warm, just open the throttle a half inch, and start it. That’s all it takes….no monkey motion, no messing around.

    That is assuming, as Steve Pierce pointed out above, the engines ignition system is set up right.

    Final hand propping advice: Always start these engines on left mag only. The vast majority have an impulse coupling on left mag ONLY. Trying to hand start with BOTH on, you have mags which are effectively timed different. This can cause kickback, or the aforementioned backfire. Even if your plane has both mags with impulse, it only needs that left mag to start, so no harm using left mag only.

    MTV
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  23. #23
    akavidflyer's Avatar
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    Quote Originally Posted by mvivion View Post
    A simple answer, in the form of a question: How does your Pilot Operating Handbook say to start that engine? I don’t have a PA-28 POH handy, but I’m guessing that resource, created by the manufacturer of that airplane suggests you use the primer. Does it specifically state that it’s SAFE to pump the throttle to start the engine?

    A simpler answer: Because there is a risk, albeit perhaps not a GREAT risk, of creating an induction fire by pumping the throttle to start one of these engines.

    In my experience, the highly qualified test pilots who flew certification test on that airplane and the engine manufacturer were the source of that POH recommendation for starting. Why would you do anything else?

    There may be circumstances and aircraft where that technique MAY be recommended by the manufacturer.

    For seven years I ran a college flight training program. We operated PA-28 and PA-28R aircraft, and later C-172. I can’t tell you the number of times I had to go start an Arrow because neither student nor CFI could start it. First thing I’d do: Take out the POH, turn to page for flooded start, cause by the time I got there, the engine would be flooded. Follow the guidance, and voila!

    On flooding: If you’re going to hand prop an engine DO NOT flood it! As I noted earlier, is hard to flood a cold engine but REALLY easy to flood a warm one. If that engine (carbureted 4 cylinder Lyc.) is warm, just open the throttle a half inch, and start it. That’s all it takes….no monkey motion, no messing around.

    That is assuming, as Steve Pierce pointed out above, the engines ignition system is set up right.

    Final hand propping advice: Always start these engines on left mag only. The vast majority have an impulse coupling on left mag ONLY. Trying to hand start with BOTH on, you have mags which are effectively timed different. This can cause kickback, or the aforementioned backfire. Even if your plane has both mags with impulse, it only needs that left mag to start, so no harm using left mag only.

    MTV

    POH also states the performance factors etc, and we all know we have refined techniques that allow us to beat those figures the vast majority of the time. Some things that you might understand would be rolling a float etc. I have seen many posts by yourself where you have stated that you figured out techniques over the years to get a plane off the water, start easier etc. To now just say that the POH is the end all and the only / best way to start an engine seems ludicrous at best.

    As far as the last statement, if I have impulse couplings on both mags (which I do) why in the bad word would I not use twice the amount of spark power to light the fire? It starts easier and better with both mags on the starter, so why not when propping it?

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    I've got no dog in this particular hunt (but glad to get additional info on hand propping, jump packs, and sat phones) but twice being the guy in the spot next to (or two spots away) from fires in aircraft and running over with a fire ext., I'm scared spitless of a/c fires. I'll admit to prime + 1 throttle pump when starting cold, but I'll probably (in the event I have to hand prop) avoid the throttle pump just because anything to reduce chances of fire addresses that personal paranoia of mine.
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    Quote Originally Posted by akavidflyer View Post
    POH also states the performance factors etc, and we all know we have refined techniques that allow us to beat those figures the vast majority of the time. Some things that you might understand would be rolling a float etc. I have seen many posts by yourself where you have stated that you figured out techniques over the years to get a plane off the water, start easier etc. To now just say that the POH is the end all and the only / best way to start an engine seems ludicrous at best.

    As far as the last statement, if I have impulse couplings on both mags (which I do) why in the bad word would I not use twice the amount of spark power to light the fire? It starts easier and better with both mags on the starter, so why not when propping it?
    Here's a question for you: What does rolling a float out of the water as a technique have to do with starting an engine? Completely different subjects, one of which MAY have recommendations in POH, others may not.

    Secondly, the POH data is derived to best serve an "average" pilot, assuming that pilot is basically qualified and trained to operate the plane. So, of course, you MAY be able to derive slightly better fuel flows, performance data, etc.

    When it comes to starting an engine, the manufacturer offers what the test pilots found to be the safest, and perhaps best way to start an engine. That information goes into the POH.....IF your airplane has one. Many belonging to members of this forum don't have a POH.

    And your comment that I've stated in past "start easier" is more than a little disingenuous, to say the least. I have on several occasions on this forum, advocated using the guidance given in the Cessna 185/206 POH on starting. If I've offered different, I THINK (hope) it was reference to an airplane without a POH.

    In any case, my latest comments on this thread have to do with an airplane which came equipped with a POH: the Piper PA 28, which I have a fair bit of familiarity with. For many years, I have advocated consulting the POH (IF THERE IS ONE) for recommendations to start an airplane.

    A Super Cub or a PA-12 was never provided with a POH, so in the context of the initial post, it's irrelevant, and I specified the model of aircraft I was discussing in that post.....a PA-28. While the Super Cub and Cruiser both came with "operators manuals" or "Owners manuals", the information there is MAYBE not so thorough as that offered in a POH, or maybe it is. I'd bet that an owners manual for a cub, if it gives starting suggestions, suggests you use the primer, if installed.

    I've posted on here to use the Manufacturer's recommended procedure in a Cessna 185 and a 206, both of which I've started regularly in almost any situation you can imagine, from plus 100 degrees to -40 degrees, and up to 7500 feet msl or so. That would be to read the POH, and use the recommended procedures there. And, oh, boy are there a LOT of folks who have "better ideas" on how to start those engines. The POH data has worked for me. If what they are doing works for them....so be it. Not my problem. But, that doesn't mean its right.

    BUT, this discussion was about starting a small, carbureted Lycoming engine. Those engines were designed to be started with a primer....why else would the manufacturer install primer fittings on their cylinders?

    Good on you for having impulse on both mags. Most don't. And, frankly, the average pilot simply doesn't know if his engine has dual impulse couplings or not. So, my recommendation was, unless you KNOW your engine has dual impulse couplings, ALWAYS start on left mag only. Sorry, i should have added that wording. As I pointed out, even if you do have dual impulse mags, there is no harm at all in starting on left mag only.

    So, here's a question for you: You walk up to a Cub you've never flown. How do YOU know whether it has dual impulse or one? This is a question for pilots, most of the folks on here are pilots, not mechanics. THAT was my point: If you don't know for sure, start on the left only. Sorry if I confused you.

    And, lest someone else chimes in with "Well, my airplane has an "Off/Left/Right/Both/Start" positions on the key starter switch, so I can't select left mag only for start. If that's the case, that switch is set up to turn the RIGHT mag OFF when you select the "Start" position. When you release the switch from the "start" position, it automatically re-connects to "Both". So, in those cases, the switch is selecting the appropriate mag for you. OR, both your mags are equipped with an impulse coupling.

    But, why would a manufacturer actually install an ignition switch that turns off one magneto for start? Maybe because most of these engines are DESIGNED to start on left mag??

    And, finally, an FYI: Not many floatplanes I've flown came equipped with a POH float supplement that gave a lot of detailed information on how to get airborne. There's a lot of information that's just not written down in those things, frankly. And, many of the planes I flew on floats didn't have a POH or a float supplement.

    Finally, I'm not suggesting that the POH (if there IS one) offers the ONLY way to do things. Those techniques and procedures offered therin, however, have been tested by the manufacturer to work reliably under most circumstances. So, I'll start with the POH, and go from there.

    So far, the POHs I'm familiar with do a great job telling you how to start the engine.

    As always your mileage may vary.

    MTV
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  26. #26

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    Here is a direct quote from a Lycoming document:

    "Lycoming engines of more than 118 HP have a throttle pump which can be used for priming under moderate ambient temperature conditions while turning the engine with the starter."

    Priming with a primer is an open loop system. You pump fuel into the induction system and hope you got the right amount. Too much and the induction system becomes flooded and the engine doesn't start. Too little and the engine doesn't start. Now you have to decide which.

    Starting with the throttle pump is closed loop. The engine cranking starts with a lean mixture and, as cranking continues, the mixture is progressively richened until the engine starts. For the conditions in which I operate, the engine starts in 2-3 seconds with no more that 2 throttle cycles. All the fuel is ingested by the engine and there is no possibility of fuel pooling in the induction system.

  27. #27
    stewartb's Avatar
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    This is a thread about hand propping. If you're a throttle pumper you'll never find the engine's sweet spot for priming and that'll make hand starting more frustrating than it needs to be.

    FWIW, I used to be a throttle pumper until I caught my own plane on fire. I'm more careful since. Now with fuel injection? If I over prime the excess fuel drips out the sniffel valve in the bottom of my induction. I don't like raw fuel dripping in my cowl so I pay attention to priming FI, too.
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  28. #28

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    And here is what the 1975 Cherokee Archer Pilot's Operating Manual says about cold starting (hand typed and may not be exactly verbatim):

    <quote>
    1. Open throttle approximately 1/4 inch
    2. Turn master switch on
    3. Turn the electric fuel pump on
    4. Move the mixture control to full rich
    5. Engage the starter ...
    6. When the engine fires, advance throttle to desired setting. If the engine does not fire within five to 10 seconds, disengage the starter and prime with one to three strokes of the priming pump. Repeat start procedure.
    <end quote>

    Now I ask anyone here who operates a Lycoming O-360 - would you crank a cold engine for up to 10 seconds without priming on a cold day. Of course not. The procedure is totally worthless and probably explains why flight school students who are taught to follow the Piper procedure have so much trouble starting the engine.
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  29. #29
    wireweinie's Avatar
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    This is why HAND PROPPING is always such an entertaining subject. LOL!

    Web
    Life's tough . . . wear a cup.
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  30. #30
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    Just a comment on the OP for anyone unfamiliar with hand propping. Consider this an 'emergency procedure'. Find someone with a metric s()*! ton of time with small aircraft and have them show you the basics of hand propping. Then PRACTICE IT! You know, with your buddy riding the brakes and throttle and you swinging the prop. And do it near your hanger preferably on pavement. Once you find the right combo for your particular aircraft, start practicing with a cold engine. Then a hot engine. Find out what you need to do differently and keep that in mind. If you fly floats or skis, find out what particulars you need to practice for those configurations. And remember to practice safely. In the real world, starting the aircraft won't help if you have a broken arm or skull (or the aircraft leaves without you).
    Then go get a jump pack and keep it charged and in the aircraft. Hopefully the jump pack will work for you. But IF IT DOESN'T you now know how to hand prop the engine and fly home.

    Web
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  31. #31

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    Quote Originally Posted by wireweinie View Post
    Just a comment on the OP for anyone unfamiliar with hand propping. Consider this an 'emergency procedure'. Find someone with a metric s()*! ton of time with small aircraft and have them show you the basics of hand propping. Then PRACTICE IT! You know, with your buddy riding the brakes and throttle and you swinging the prop. And do it near your hanger preferably on pavement. Once you find the right combo for your particular aircraft, start practicing with a cold engine. Then a hot engine. Find out what you need to do differently and keep that in mind. If you fly floats or skis, find out what particulars you need to practice for those configurations. And remember to practice safely. In the real world, starting the aircraft won't help if you have a broken arm or skull (or the aircraft leaves without you).
    Then go get a jump pack and keep it charged and in the aircraft. Hopefully the jump pack will work for you. But IF IT DOESN'T you now know how to hand prop the engine and fly home.

    Web
    ...and that, I believe, is that. Best advice (at least IMO) on this thread.

  32. #32

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    There are many of us who hand prop every start every time as we lack the required starter, ring gear, and associated wiring. It is not an emergency procedure, it is an essential skill.

    We consider a starter and ring gear a backup system, and a jump-pack something you keep around to charge your phone.

  33. #33

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    One other note on primer systems some are a single nozzle above the carburetor (0300) and suffer the same issue as carbs so take a look at your system.
    DENNY
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  34. #34
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    My '56 180 didn't have a priming system. And my J3 didn't have a starter - so I learned both ways... On my big conti I would never pump the throttle unless the starter was turning for fear of induction fire. I never got to try hand starting the O-470 but after a few hundred hours of flying the J3, I think I could do it without killing anyone if I had to.

  35. #35

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    Quote Originally Posted by NunavutPA-12 View Post
    Trying to refine my technique. These comments have been helpful.

    I was trying to "throw" the prop through the compression stroke. Now I understand (I think) that all I have to do is bring the prop to the compression stroke and then just pull it through as forcefully as I can. Correct?
    I'm not very experienced with hand propping, but I've had to do so a few times in the backcountry. When I was taught how to properly hand prop my Lycoming 0-320 by my mechanic (who thankfully flew over at just the right moment when I got stuck after my first off-airport landing), he emphasized that I should not do anything "as forcefully as I can". In fact, he specifically said that I should only use as much force as absolutely necessary and no more. The way he described it (and how I have practiced it since) reminds me of squeezing a trigger on a firearm rather than pulling or yanking the trigger. I pull it through the compression stroke and simply keep steady pressure on it until it swings. Pushing as forcefully as you can at any point could lead to a loss of balance, and that...well, nothing good can come of that.
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  36. #36
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    A supercub pilot on this forum who shall remain nameless recently hand-propped his supercub after which his supercub proceeded to chop up a wing of a nearby supercub. Needless to say, the dead battery problem got expensive in a hurry. The point being:

    Tie the tail down before you hand-prop the engine, or at least chock the wheels and be careful how far open you set the throttle; and

    Don’t park your supercub where your buddy’s supercub can chop it up.


    Sent from my iPhone using SuperCub.Org
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  37. #37
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    Good point windy. Once I had to hand prop an Ercoupe. Cracked the throttle, spun the prop, it started and immediately the throttle vibrated to wide open. Fortunately I had left all three tie downs connected to the airplane. They stretched out to their limits as the tail squatted to the ground. IF it had only been chocked, it would have gone airborne on it's own.

    Fortunately in this case no harm was done and I learned a valuable lesson. Just because the throttle is only cracked DON"T trust it to not move on it's own.

    DO NOT TRUST JUST USING CHOCKS!!!
    N1PA

  38. #38

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    Little different but starting my c-90 when warm I usually shut the fuel off because if throttle isn't advanced enough it will flood (usually in front of a large crowd) then it has to be unwound a dozen blades, if you watch mountain men you can see how easy a super cub will start by watching Marty when the impulse coupling fires it's running and that will happen to a warm engine with no effort. Every engine likes something a little different so it's just a matter of learning yours.
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  39. #39
    SJ's Avatar
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    Over 20 years ago now Jim Dickerson and I made this little hand propping guide...

    "Often Mistaken, but Never in Doubt"
    ------------------------------------------
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  40. #40
    wireweinie's Avatar
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    Isn't this the point where we all tell 'those stories' about how this same thing happened to 'our buddy'? lol

    Web
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