Inverted Engined Starting

Gang --

Some folks start inverted engines with the airplane in the normal take-off position, sitting on the gear. Some roll the plane sideways around the fuselage axis to get the engine upright. Some flip the plane upside down, pointing the opposite direction (as in inverted flight).

This is a Brodak 40 in an Oriental.

Now, my helper is my big, strong handsome wife, and neither of us are quite as agile as we were 40 years ago. We would like to develop a procedure that works for us with minimum foot work. I would say she is mildly intimidated holding a plane with a running engine.

I would prefer to just start the engine with the plane upright on its gear, and the engine inverted. Likely? Obviously, even if we plan that way, we have to have a flip plan if we get a flood.

Any suggestions appreciated.

Larry Fulwider
"The wind always blows towards the sun"

Don't get the engine too wet and have a good battery/glo driver and you will not have any problems. That inverted start always has me worried with safety issues when turning the model over.

>Don't get the engine too wet and have a good battery/glo
>driver and you will not have any problems. That inverted
>start always has me worried with safety issues when turning
>the model over.
>
>HH
Im with you Dallas,Been flying 50 + years;
the older I get , the more I am intimidated by a running engine.
Turning over a plane with the engine running, is at the top of
my danger list.

Larry, every engine has its own characteristic, but as long as it is not flooded with either fuel or oil it should easily start with the engine in the inverted position. Matter of fact, I now prefer them that way.

But again, every engine has its own characteristic. With the 35 and 40 FP, at a contest we would fuel, attach the glow plug clip, signal the judges, then give it one choke and one flip and it would be off. If we choked, then signaled the judges, it wouldn't work. If we were flying at home doing flight after flight, on subsequent flights we would simply fuel and go. There would be enough residual fuel to start without choking.

On the 53 and pipe engines, we would fuel, attach the glow plug, then hand turn slowly several turns until we felt a "bump". We could then signal the judges and it would usually go with one flip.

If you don't feel the "bump", try one choke and then flip. If it doesn't start, try another choke turn and then flip. If it takes three of these to start, the next time start with two. Then add another if that isn't enough. Then the next time start with three. Once you get the procedure down for that particular (type of) engine, you should be able to repeat the process on a day to day basis.

Just remember, however, that if the engine is warm, like you have just run it and are getting ready for another flight, try a couple of flips first before you even choke. It may have enough residual prime to start. If you choke it under those circumstances, you are likely to flood it.

Remember, it is better to have too little prime than too much. Once it is flooded, that's when the problems begin. If you do flood the engine, if you don't want to turn it over, remove the plug and flip the prop a couple of times to try to run the prime out. Then also blow out the plug and make sure it is buring bright before putting it back in.

A little practice and you will soon become an expert. You will be able to walk up to the line, do your thing, and get those "magical" one flip starts that we and the judges all appreciate so much.

Do What Len said it works every time!

Hank

>Larry, every engine has its own characteristic, but as long
>as it is not flooded with either fuel or oil it should
>easily start with the engine in the inverted position.
>Matter of fact, I now prefer them that way.

Very Encouraging!

>But again, every engine has its own characteristic. With
>the 35 and 40 FP, at a contest we would fuel, attach the
>glow plug clip, signal the judges, then give it one choke
>and one flip and it would be off. If we choked, then
>signaled the judges, it wouldn't work. If we were flying at
>home doing flight after flight, on subsequent flights we
>would simply fuel and go. There would be enough residual
>fuel to start without choking.

I think the Brodak 40 is a cut below the FPs

>A little practice and you will soon become an expert. You
>will be able to walk up to the line, do your thing, and get
>those "magical" one flip starts that we and the judges all
>appreciate so much.

Five flip starts on an inverted would make me ecstatic!

The best way I have always used is to burp the engine upright before fueling. Then once you are in place. A good battery is all you need. to get one or two flip starts inverted.

>
>>
>Why?

I can't speak for Len, but I generally agree with him. I find it a lot easier to choke and back-flip the engine with it on it's feet, instead of inverted. I will burp the motor upright before attempting it (since oil runs back into the motor from the pipe), but, other than that, it's a lot easier to get fuel in the cylinder so it will start, but not have so much in the crankcase that it starts and then floods itself out like it does with the engine upright.

Brett

At Huntersville, one of the very good intermediates was Alan Buck. Since he destroyed his airplane, I didn't want to bother him. Any relation?

>At Huntersville, one of the very good intermediates was Alan
>Buck. Since he destroyed his airplane, I didn't want to
>bother him. Any relation?

Not to my knowledge.

Larry to bad you were not at the field this morning I would have shown you my method as I had my Tucker Special with a inverted Rustler 40. Since no one but me was there I put up 5 flight using a stooge in perfect weather.There was at least 20 guys flying RC and they all stopped and watches me fly my first flight.They always wonder how I am going to launch the plane.I had no more than 15 total flips for 5 flights to get the motor running.Three flips per flight.I prefer a inverted motor as it will not flood during fueling.Pre firing the motor with a prime before connecting the lines is a good idea but this morning I didn't even bother doing that.Your wife can sit and watch and I will hold your plane.Your wife and mine talked for a hour last Sunday at the contest.See Ya
Ed

Hi Larry, If you are not opposed to it, I have found the best way to get me in the air and keep my wife from running out of patience is to use a starter!! No flooding, no flipping and never a finger in harms way. I know that there are a bunch of guys who POO POO using starters, and I do understand that from a purist stand point they seem like a cheap way out but since starting to use one I have had exactly zero trouble getting guick engine starts and a wife that does not mind launching for me, of course this is just my opinion, Dave Markley

Dave --

Are starters legal in PA? I am not being a smarty pants here, I honestly don't know. Never thought about it before. I can't remember anyone using one except in practice.

Since the 5 points for starting the engine were eliminated there is not been a prohibition against an electric starter. Prior to that there was.

Ed --

Yeah, I imagine we'll be doing some flying together. You can show me the ropes! Our wives did indeed hit it off!

I happen to be flying the same motor and plane setup as you.(I built this Oriental not an ARF)2 years ago and have put a good number of flights on this plane and motor.I really enjoy the Brodak 40 except for the first start of the day!I have a hard time starting the motor on the first flight of the day after that it hand starts usually within 2 flips.I have tried prime starting it ,choking it,ect .I have recently just decided to start it with the starter for the first flight then I hand start the rest.This is much less frustrating.As for using a starter at a contest I do not beleive there are any problems.

Dennis Pedersen <><

Electric/mechanical starters are perfectly legal for both AMA and FAI Stunt events. It seems to me that the starter is a good thing for all...judges, contestants, spectators. It makes the flying move faster, and a lot better flying to be seen without bandages on fingers.

A Bruline air filter will help the starting of an inverted engine. Choke an inverted engine, and the fuel will drain down the venturi and into the filter. Without the filter, it runs out on the ground. You would have to choke the engine through quite a few rotations to actually flood it. You get a little fuel in the filter, and you have fumes to suck into the engine, and we know fuel fumes are easier to lite up than liquid. They work great on upright and sidewinder setups, too. Just squirt a couple drops of fuel on the filter. Steve

LAST EDITED ON Jun-12-06 AT 01:19 PM (CST)
 
>>
>>>>
>>Why?
>
> I can't speak for Len, but I generally agree with him. I
>find it a lot easier to choke and back-flip the engine with
>it on it's feet, instead of inverted. I will burp the motor
>upright before attempting it (since oil runs back into the
>motor from the pipe), but, other than that, it's a lot
>easier to get fuel in the cylinder so it will start, but not
>have so much in the crankcase that it starts and then floods
>itself out like it does with the engine upright.
>
> Brett

Maybe I'm living on another planet. Or a parallel universe, Twilight Zone style, in which everything is almost, but not quite, identical. Little differences, like starting inverted B40s. (Remember comedian Robert Klein's "scary music" impression? LOL)

Hi
I run LA 40s but all engines are similar in that the want a definite starting procedure. The trick is to find it. I do know a number of people with Brodak 40s and some start them with out flip the plane. Generally if you can't chock the venturi or get a prime in the engine somehow you'll need to fip the beast. I believe the Oriental does't have the engine buried like say a Nobler. I've found that my LA 40s start the same mounted any way if I appropriately modify the priming dance. First be aware that the number of chocks is determined by the needle valve setting. Maybe the thing to do whould be use a test stand to determine the optimum chock sequence, or turn the plane over. What you need to find out is what number of chock revolutions and open revolutions are needed. Trial and error un fortunately. Keep notes. After you've this out you need to find out the difference there is when the carb is upside down. My LA 40s need 3 times the number of chocks in the inverted position. I also give the engine 12 unchocked turns, then battery. I very rarely need a second flip. As you are searching for the secrets of life start with too few and work up. Be aware that if you go through a bunch of chocks and flips the count will be off. Just add more the next time until you zero in.

Smoothie Bill

Larry,

You've gotten really good advice about how to start the engine so this is for safe inverted starts.

Have your assistant (beautiful wife/ugly girlfriend whatever) hold the airplane in whatever manner they are comfortable with. When the engine is started and you have removed the batter, the assistant should point the plane straight up and not try to turn it over. You get the plane from the top side, assistant clears out of the way and you set the plane down. The assistant then takes it from you. Very safe way to do this proceedure.

LAST EDITED ON Jun-13-06 AT 10:40 AM (CST)
 
I'm surprised that no one has mentioned unintentional flooding while filling the tank. When the tank is full, there is usually some fuel forced forward into the venturi. If the crankshaft transfer port is open, this will flood the engine. You don't know why it won't start and its gonna take a lot of flipping to clear the engine. Many people will lose patience while flipping and add more prime to an already flooded engine. Of course you can always invert the airplane. Starting with the engine upright helps the excess fuel to drain and starts are generally easier from a flooded beginning. this is why I designed the Mustunt series to incorporate upright engines for beginners.

I think it is unnecessarily dangerous to flip the airplane, especially when the cause of flooding is so easy to prevent.

Always, when fueling, first turn the prop backward against compression to close the crankshaft transfer port. This should give you a dry engine to begin with. It will take a measured amount of prime/choking to start a cold engine. Usually, a few flips of choke is enough followed by slowly turning the engine over with the prop tightly held to feel the "bump". It is now ready to start. Hot engines frequently don't need priming/choking.

My airplanes are tightly cowled so choking is out of the question. Before fueling, I rotate the prop backward against compression to avoid flooding. To start a cold engine, after fueling, I rotate the prop forward against compression to open the crankshaft transfer port and use a small syringe/glue gun to squirt a small amount of fuel directly into the intake. Then rotate the engine to get a bump and the usual first flip start. If it fails to start in the first couple flips, I simply grab my starter. Typically, I get first flip starts. When the engine is warm, I never prime. It starts immediately or I grab the starter. For two stroke engines, I prefer not to use the starter as it is easier to just flip the prop and go. Maybe once in 20 starts, I will grab the starter if it doesn't start by hand flipping in the first two or three flips. In competition, you have a time limit for starting. I give the engine a couple of flips, then, if the engine doesn't start, grab the starter. I always start on the gear. I have never lost starting points.

I never start four stroke engines by hand, partly, because my smallest four stroke engine is a .72.

I strongly recommend starters to everyone. Having one nearby, in arms reach, seems to insure the engine will start promptly by flipping. I guess its presence intimidates my engines. In any case when I go to practice, I count of getting in a flight every 10 minutes. I always have charged start and starter batteries.

Some guys almost always get prompt hand starts and never buy a starter. At the World Championships in Liverpool in 1978, starters were not yet banned under FAI rules. Bob Geiseke couldn't get prompt starts in the cold, wet, English air. He asked to use my starter. He probably hasn't used one since, but when you need prompt starts it is a necessary backup.

First, It is necessary to understand how to avoid flooding the engine while filling the tank. Second, have a proper technique for priming/choking. Third, have a starter backup. It will seldom be necessary, but it does put an end to endless flipping.

It is altogether too easy to come up with solutions which are unique to particular situations. I usually fly by myself with a stooge. My Ro-Jett 76s never need prime for hot starts. The situation becomes more difficult when flying with a group of other flyers. When the engine is neither cold, which has a definite starting technique, or hot, needing no technique, it is sometimes difficult to guess just how much prime might be necessary. I tend toward little or no priming, usually start with a couple of flips, but keep the starter handy. I am much more likely to use a starter when flying with a group than when I'm by myself. Hot and cold starts are easy. Warm starts may be tricky unless you fly with others often enough to develop a warm engine technique.

Everything Al says is correct. The only problem I have with electric starters is when you have a flooded inverted engine and try to start it without fixing the problem you will bend or break things. This could be the piston, rod or crank. 'Cause the fuel in a liquid state is difficult to compress, something else has got to give.
I have an R/C P51 with an Enya .90 4 stroke mounted inverted and hand start it all the time. Choke once, set the throttle at medium idle and it just lites off and sits there in the idle mode. If I were to use a 4 stroke on a stunter for sure I would use the carb as the venturi and do the same. All that is needed is a throttle connection to set the carb for a stunt run AFTER it is started. Even a caveman could do it. RJ

Engines often become easier and easier to start as you gain experience with them. It seems to me that a front intake inverted engine is less likely to flood than an upright engine. Fuel just runs out the venturi. You notice that the FAI team racers are all, and the last generation of late lamented fast rats were mostly, inverted engine airplanes. This in events where instant starts, hot or just warm are essential. Basically do whatever your engine needs. If it wants a starter, use a starter.

LAST EDITED ON Jun-14-06 AT 01:36 AM (CST)
 
In defence of Al with his electric starter, isn't it just plain sense to turn the motor over by hand before any power is applied to the glo plug? By doing this, there is no danger of bending anything in the engine. Then it doesn't matter what system we use, hand flick or electric. As Al says, you should have good batteries for both glo and starter, especially the glo as with the starter it will pump vapour into the cylinder and put the glo out. Oh, by the way, I don't own an electric starter! With ST and MVVS (ri/re and can't choke) engines there is always instant starts in all weather.

The only 4 stroke I have is an Enya 120R with a 16" x 8" prop which starts beautifully by hand Al BUT shhhhhhh..... it starts at low throttle in an R/C model. Inverted engine which means excess fuel just runs out of the exhaust and a gentle bump back against compression by holding that 3" spinner. Still got 6 fingers on each hand. Hang on! 5 fingers! Gave up playing the banjo!

All the best Al. How's that new model going?

HH

PS. Jim, I'm with you. I always start with model on wheels (engine inverted) as I find it hard to flood it. Also as mentioned before I hate helping anyone who turns the model inverted to start as I find it a safety issue turning the model over. Personal hangup so no need to hit me on the head and try to convince me otherwise. If most of my comp flights have been starts within a couple of flicks, how much better will starting with model inverted be. Whilst I'm turning that model over I can be half way to the handle.

HH again

The FAI TR engines are rear intake with the intake facing up! Most BTRs are front intake with the engine inverted. Almost all other racing classes are "profile type" with side mounted engines. The ideal is 1-flip starts. Getting there is a matter of getting used to the equipment and not making a big deal of it.

I have an electric starter in my pit box and will sometimes use it when starting a cold engine. It's just plain easier!

Actually getting there is a big deal of getting used to the equipment.

An engine that will start is a prerequisite for getting used to the equipment

Yeah, Don. Even though you tried not to make a big deal of using an electric starter, we saw you doing it during a SSR race last year--gotcha! I assume you have either broken that engine in by now, or gotten rid of it? Or perhaps you will give it another try this weekend?

When I started flying a couple years ago my third stunter was the igNoblarf. Half the folks at the field made a big deal out of starting an inverted engine and gave lots of advice including do's, don't, and sympathy in advance. I had trouble the first few trips to the field. Half of it was that the engine was not broken in. The other half, like Smoothie Bill said above, was converging on the sequence. A little practice proved that starting an inverted OS is no problem at all. I have seen folks with inverted B.40s. These take longer to break in and seem to be harder to start inverted. If I'm launching, I would rather people try to learn to start them on the ground than help them flip the plane over. Before I flip a plane over I really have to trust them. I try to help out when I'm at the field, but once someone scares me with their flipping methods you won't see me jump up to help out.

From a pilot's perspective, I have the greatest respect for the pitman in racing. Every plane is different, the setups are different (generally due to the rules) and not a little bit different like stunt planes---a lot different. A high compression .15 rat with bucket venturi running pressure and shutoff contrasts sharply with a Fox racer on suction. Chances are that if the rat doesn't start on the first flip it isn't going to start at all because you burned out the prime and then flooded it. The pitman has to memorize maybe a dozen different starting routines. Worse, he has to instantly observe, diagnose and treat a racer. If it won't start on the first flip people say the pitman ain't getting it done. If it won't start after half a dozen flips you have little chance of winning. Knowing how (or learning how) is what makes it fun!

Dave Hull
LA_Flyer

To tell the truth. The starter incident. I knew I was DQ'd as soon as I picked up the starter, but I had been frustrated all day trying two different engines, having almost no success getting either one to run.
Turns out the problems were DUHHHs! The one engine was the one that was teched after the NATS win. After I got it back I didn't torque the bolts, so the backplate and the head were a little leaky!

The other one was the other engine we used at the NATS that had an impact with the ground due to an i**ot tangling our lines. It looked OK until you looked just at the underside of the mounting lug and saw the hairline crack! Like I said a couple of DUHHs.

Larry

I started running the Brodak .40 this spring and had fits getting it started inverted till I found out I was overpriming it. One or two priming flips and you should get a bump on the pass thru compression while holding the prop. If you don't get the bump do one more prime. I talked to Big Art Adamissin about it and he said he found the same thing. He says he even tries not to hold his finger too tightly over the venturi when he primes it.... he said that with his typical smile. But from that day on I have had consistant one flip starts.

bob branch