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-   -   One flick starts, is this a myth? (http://www.rcuniverse.com/forum/everything-diesel-87/11442586-one-flick-starts-myth.html)

franchi 03-13-2013 01:35 PM

One flick starts, is this a myth?
 
Hi:

I have heard of starting a diesel engine by only having t flick the prop one time. This was done in Combat and Team Race events. Is this possible? If so how is this done?

I have a MVVS D7 that may be be broken in enough to do this and a ST G20-15D that has had a fresh chrome job to try one flip starts but I am wating for warmer weather. I also have an O.S. FP .40 with a Davis head that I am afraid to flip with my finger! It has to be started almost dry with no prime or choke into the engine or else it will be flooded. If this engine becomes flooded, it becomes nearly leathal!

Any suggestions?

How many flips of the prop do you take to get your Diesel engine started?


Tia,

Franchi

Mr Cox 03-13-2013 02:00 PM

RE: One flick starts, is this a myth?
 
I have a peewee that will fire on the first flip. The trick is to prime the side of the piston, wiggle the prop a little back and forth around the opening of the exhaust port and then flip.

Engines with mufflers that don't enable priming of the piston port, and need priming through the carb, are much harder to start.

ffkiwi 03-13-2013 02:14 PM

RE: One flick starts, is this a myth?
 
Nope definitely not a myth-very much true-but not for every engine. Particularly true of well setup sideports such as the Mills 75 and 1.3 and MP Jet Classic, but also of other good well fitted front induction diesels, such as the Oliver Tiger. However-it does require a well run in motor, optimum piston fits, and the user being thoroughly familiar with the engine. 'Thoroughly familiar' means knowing exactly the right starting settings, amount of prime and/or choking required, the type of flick-ie flick or hit depending on what the motor prefers. None of this you acquire except through experience. Team race engines are a special case-usually rear drum, and being much more metallurgically advanced than run of the mill diesels, plus having refuelling valves, automatic (and adjustable) priming etc. Once again, pitmen are usually very experienced engine men-they have to be-since the pilot is not in any position to do much about the engine settings!.....and since races are won or lost by tenths of a second, first flick restarts are highly desirable.......but also bear in mind during a pitstop the engine is usually hot-and at running settings and clearances-the same engine may not be a first flick starter from cold!

In answer to the question posed-anywhere from one to fifty.....depending on the engine [and I have hundreds!] . In anycase, whilst one flick starting is useful in some situations, it's not the be-all and end-all....an engine that starts quickly as distinct from first flick is what is generally required. I have engines that take forever to start-but once running, run like the clappers-this usually means they are nearly worn out.....

I would expect that both your D7 and G20 could, with the right setup, potentially be first flick starters-equally, I wouldn't expect either of them to be able to do this on every occasion....

ChrisM
'ffkiwi'

AMB 03-13-2013 02:24 PM

RE: One flick starts, is this a myth?
 
My sure start 049 cox has done it same method as Mr Cox just stated, I am happy with 3-5 still not bad martin

ffkiwi 03-13-2013 02:29 PM

RE: One flick starts, is this a myth?
 
And most of the spring starter equipped DC Quickstart diesel range will also do it-once run in, but of course that doesn't count since you aren't flicking. .....

ChrisM
'ffkiwi'

AMB 03-13-2013 02:42 PM

RE: One flick starts, is this a myth?
 
I have not used the spring start on the Coxs they do not fit over the wood props well so flip, electric fingers a no no on them martin

ffkiwi 03-13-2013 03:33 PM

RE: One flick starts, is this a myth?
 
1 Attachment(s)
But the DCs use a different setup Martin-the spring starter engages a lobed cam located behind the prop, not the prop itself. This was not the original setup, DC originally used an open end hook which did fit over the prop a la Cox. Presumably they found it was not as effective as using a separate cam. It also has the advantage of a smaller hook (actually a fully closed loop) and a spring end at 90 degrees to the shaft axis-lessening the chance of the spring vibrating into the path of the prop disc when the engine is running-I've had this happen with box Coxes and disastrously with a G-Mark Humming Bird .03-the latter 'eating' its own starter spring.......
The pic below shows the DC setup, and shows a good view of the lobed 'Quickstart cam', this example on a 70's era DC Dart 0.55cc
ChrisM
'ffkiwi'

AMB 03-13-2013 03:45 PM

RE: One flick starts, is this a myth?
 
Brillant method and simple too marin

ffkiwi 03-13-2013 04:46 PM

RE: One flick starts, is this a myth?
 
1 Attachment(s)
Its not entirely perfect Martin-the cam can slip against the prop driver, and the prop can slip against the cam if not done up very tight-the gripping surface of the cam is not to be compared with the knurled face of the prop driver-some cams are plain, some have a rudimentary radial pattern surrounding the shaft hole, and others have 4 raised dimples that fit into the usual depressions in the back of most props. The plain ones seem to be fitted to the Dart, and the glow Bantam .75cc and Wasp .8cc, the others to the Merlin, Spitfire and Sabre.
The little Bantam .75cc was my first ever brand new engine-an Xmas present from my mother in 1970-and I usually ran it on a Cox black 6x3 nylon. That prop would often come loose on starting with a quite disconcerting 'crack'-and in hind sight it was probably the combination of a smooth cam AND a 6BA screw prop fixing as opposed to a 4BA (or larger on the bigger motors) nut on the Dart that led to the problem-you just couldn't develop much tightening torque on a 6BA std cheesehead screw, whereas the Dart , Merlin etc had nuts which could be well tightened. These days-just as with TDs -I'd simply use an allen head screw rather than a slot head screw.
Interestingly the photos below show two of several (the others were Allbon Darts) DC Darts I picked up recently from a deceased estate-the one on the left is 'normal' [and was the one I showed in closeup in the previous post, the one on the right has a Bantam type shaft with a 6BA screw in prop stud [the spinner appears to be a home made item]-so is the crankcase a Bantam one [it had machined transfer passages up each side] and the shaft a Bantam one as well?....or is it a standard Dart crankcase with an oddball shaft. Now the Bantam (which appeared in late 1959....just in time for Xmas.....DC weren't silly!) used the Dart crankcase-machined differently-and had the same 0.350" stroke as the Dart, but a larger bore of 0.410 (same as a TD 051!) and remained in production till superseded by the DC Wasp in 1971. [the Dart continued on in unbroken production]. Now the Wasp was an entirely new engine owing nothing in its ancestry to either the Dart or the Bantam-so presumably the remaining useable parts from Bantam production-the bottom end-were diverted on to the Dart production inventory.
I'll only find out for certain once I've stripped and cleaned the motor-the valve port and gas passage size will tell me whether its a Bantam crankshaft or not, or merely a variant Dart. The prop driver is definitely a Bantam type-seating on splines rather than a taper, and has finer knurling than the standard Dart. You can also see the Quickstart cams in front view in the second photo.
.....things you didn't know you didn't know...........actually I have seen at least one other Dart like this on Ebay in years past-so at least two were produced!

ChrisM
'ffkiwi'

fiery 03-13-2013 05:11 PM

RE: One flick starts, is this a myth?
 
Engines I have one-flick started (though not routinely)

1. Oliver Tiger Major Mk II (first start first fire up out-of-the-box).

2. Taipan Tyro

3. DC Dart (cheating with the "quick start" device shown by Chris above)

4. Mills and Mills copies (MP-Jet 040)

Nothing unusual about it once correct settings and priming technique are found.

A really good piston and liner fit is essential.

AMB 03-13-2013 05:12 PM

RE: One flick starts, is this a myth?
 
Chris with the metal to metal contact can see where it could slip unless tighter than duzy had they had a small pin in the prop driver that would engage a hole in the disc would have solved the issue martin

earlwb 03-13-2013 05:26 PM

RE: One flick starts, is this a myth?
 
The trick is a little priming done via the exhaust port. Depending on the engine it can be a mere drop or two or more as the engine gets larger. The team race guys, dribble a bit of fuel into the exhaust port and give the engine's prop a quick brisk flip and the engine will fire right on up. Some of the diesel engines have a special muffler priming port for that purpose. The team race engines were usually run without a muffler of course. Some team race engines had a priming port or hole built into the exhaust stack on the engine too. That way they could bolt on a muffler.

I have done some single flip starts with some of my engines; My Mills and Mills like repliicas, a couple of Cox .049 diesels, some MJ-Jet vintage replica engines, my OS 40LA diesel, my Fox .45 diesel and my MVVS 10cc diesel.  But I haven't been able to get the engines to cooperate when recoding them on videos though.



ffkiwi 03-13-2013 05:43 PM

RE: One flick starts, is this a myth?
 
Some of the early diesels DID have a pin in the prop driver which fitted into a suitably drilled hole in the prop Martin-the very first Mills 1.3 springs to mind.........and some others-Letmo 0.6-the original Swiss Dyno 2cc. On the spring starter side, the biggest diesel I've seen this fitted to is a 1.5cc, and the biggest glow 2.5cc (Cox Olympic and Sportsman 15's)-I wonder if this is because the strength of spring required for bigger engines means they can a) cause injury if the prop strikes you under spring rotation or b) cause damage to the engine if engaged with a flooded or over compressed engine...? [that being said, I'm aware that a spring starter option was developed for the 40cc or 50cc Quadra engines popular for 1/4 scale models in the 80's........but it was an aftermarket accessory not a manufacturer's option]

talking about prop slippage-it still mystifies me why the Allbon Dart .55cc and Spitfire 1cc came out with plain unknurled prop drivers in the early versions-when other competing makes-ED for example, were already going to great lengths to make very deeply knurled/serrated drivers-look at those fitted to the ED Mk2/Comp special, ED Bee and Hornet and Mk4 Hunter........

ChrisM
'ffkiwi'

ffkiwi 03-13-2013 06:05 PM

RE: One flick starts, is this a myth?
 
1 Attachment(s)

Quote:

ORIGINAL: earlwb

The trick is a little priming done via the exhaust port. Depending on the engine it can be a mere drop or two or more as the engine gets larger. The team race guys, dribble a bit of fuel into the exhaust port and give the engine's prop a quick brisk flip and the engine will fire right on up. Some of the diesel engines have a special muffler priming port for that purpose. The team race engines were usually run without a muffler of course. Some team race engines had a priming port or hole built into the exhaust stack on the engine too.
Team race engines are usually refuelled using a pressurised refuelling system, and have a fairly mechanically complex valving system either built into the back of the engine or into the tank [some of the modern ones have the valve AND tank built into the back of the engine]-and one of the features fairly universal since the 1980s in these engines is the tank overflow from refuelling is directed to prime the engine, and in some cases the excess used to provide localised cooling on the cylinder. Part of the complexity of the valve setup is adjustment features to allow this overflow to be adjusted to suit the specific starting requirements of the engine.

ChrisM
'ffkiwi'

earlwb 03-13-2013 06:21 PM

RE: One flick starts, is this a myth?
 
You got me there, I honestly don't remember anyone using anything complicated for fuel systems in the planes but yeah they did have some pretty fancy refuelers strapped onto their arms though.

But here are some cool team race videos though, lots of one flip starts with hot engines too. The first video shows some really great one flip starts too.

[youtube]http://www.youtube.com/watch?v=Q46xEAoGtT0[/youtube]

[youtube]http://www.youtube.com/watch?v=vJk97fzG4T0[/youtube]

[youtube]http://www.youtube.com/watch?v=mzBGTrmYbJA[/youtube]

raglafart 03-13-2013 07:34 PM

RE: One flick starts, is this a myth?
 
Wal and I have regularly competed in our local NSW's Diesel Goodyear races.
It's a speed limited event restricted to 27 for 10. Any faster and you have to have an extra pitstop.
Tuning the engine (before the race) to give that speed is imperative. You have to get as close to 26.8 for 10 as possible.To win you simply have to have very quick pitstops.
We have won this contest quite a few times and when and if we win we have 1 flick starts throughout the race heats and finals.
We have no special tank or primer. It's a squeeze bottle event.
We are up against some very well known long time expert teams and have managed to become one of the fast teams.
You have to have a good engine, we use a Nelson 15 D side exhaust. The problem isn't making the speed, with the Nelson it's getting to go slow enough and also getting it reliable throughout the tank so it doesn't get fast or slower from the beginning of the tank to the end.
I have in the I past favoured the big bang style of flick bending only from the trunk. At the start of a race I'd hold the outboard tip of the model down with my left toe. The swing would start from above head height. Very rarely did I not get and instant start. However, if I missed the prop as I've done a few times, you can impale the tip of your finger on the very sharp point of the APC props we use. On one occasion I wound up with temporary nerve damage !!!!
My back has now made significant protests to this style of pitting so now I have to kneel (not easy for me with a full RH knee replacement) and I can't get quite the same amount of power into the swing, but it was still good enough to win the last contest we entered.
I have the prop set at 1 pm.
It works for Wal and I and also his R250 diesel is of course a 1 flick starter too.
As anyone will tell you, you need a round cylinder liner and a well set up piston sleeve. The correct comp/prop/tank/fuel and lastly technique, then it's a doddle.
Take a look at the YouTube pit stops of Grant Potter at the 2008 WC to see perfection
Here's the link, the clip is only 6 seconds in total, he catches, refuels and restarts in even less time!
[youtube]http://www.youtube.com/watch?v=hLp1EucCQWw[/youtube]

qazimoto 03-13-2013 07:34 PM

RE: One flick starts, is this a myth?
 
1 Attachment(s)
F2C diesels aren't the only c/l class that use tank overflow exhaust primers. We use them in Diesel Goodyear particularly on PAW GTS and Rothwell R250 engines.

With these engines and the priming system shown below first flick starts hot or cold are the the norm.

The tank is filled with a "squeeze" bottle fitted with a "male" insert that matches the spring loaded filler valve (the brass thing midtank)

The uniflow front feed tank has it's breather pipe/overflow in the top of the outside corner.

It's piped through the tubing to the pipe mounted on the top engine lugs.

Note that it's bent towards the inside of the model rotation. This ia to point the overflow jet of fuel away from the pitman's knee. :D

http://images.rcuniverse.com/forum/u...40/Us54991.jpg


A smaller diameter pipe delivers the fuel overflow during filling to the engine exhaust.

It's pressure is controlled by a careful selection of an inner pipe at the front overflow.

The procedure is this. The tank is filled with the fuel shutoff closed. The prop is held back against compression so the exhaust port is closed.

When the tank is filled, the overflow washes the side of the closed piston. As soon as sufficient prime has been made the cutoff is opened and the prop is flicked very hard. About 90% of the time it starts first flick


http://images.rcuniverse.com/forum/u...40/Ql35177.jpg


Ray

AMB 03-13-2013 07:50 PM

RE: One flick starts, is this a myth?
 
First time have seen that set up for a prime clever. video amazing that is a quick pit and fly you have it down martin

greggles47 03-13-2013 07:59 PM

RE: One flick starts, is this a myth?
 
Apart from the TR engines noted above, any motor CAN be a one flick starter.

All you have to do is spend a lot of quality time getting to know each engines peculiarities and catering to what it needs. Some like to be drippling wet, others dry.

What I have found is that engines will start readily - one or two flicks- once you get the "bump". If you don't know the bump it's time for the quality time I mentioned.
Get the engine primed sufficiently (whatever that is) and turn the prop until you feel it half fire (hence bump). When you get to shat stage, give it a good flick and it should start, if your settings are close it'll run, otherwise you may need to go again until the runninng settings are established.

The real skill is determining what each motor needs.

Greg

franchi 03-14-2013 04:55 AM

RE: One flick starts, is this a myth?
 
Hi:


Thanks for all of the information!

I guess that I need to spend more quality time with my Diesels!

I have been ostracized for not starting my Diesel engines via an electric starter. I was tod that hand starting is out of touch with moderen times. Perhaps if we would permit electric starters to be used in our events, more people would join in the hobby.

Stay well my friends,

Franchi




raglafart 03-14-2013 05:16 AM

RE: One flick starts, is this a myth?
 

Quote:

ORIGINAL: franchi

Hi:


Thanks for all of the information!

I guess that I need to spend more quality time with my Diesels!

I have been ostracized for not starting my Diesel engines via an electric starter. I was tod that hand starting is out of touch with moderen times. Perhaps if we would permit electric starters to be used in our events, more people would join in the hobby.

Stay well my friends,

Franchi




In inexperienced hands, an electric starter can be the kiss of death to a diesel!
A great deal more care is required as any flooding will inevitably lead to damage.
Bent rods and broken crankpins being the usual mess along with ovalised big end bushes in rods and worn wrist pins.
It's not to say it can't be done, but it does carry risk if not done properly.

AMB 03-14-2013 05:31 AM

RE: One flick starts, is this a myth?
 
The ones who are mis-informed or lack on knowledge are the ones who say an electric starter is needed if an engine set right it will hand flip start diesel or glow\ if you have a diesel with lower compression than normal a starter may help, there is a safety factor of course your finger will not get whacked but thats why we have safety sticks to flip with
I do use a a starter on my Irvine 53 conversion lights off in a second or two martin

Jim Thomerson 03-14-2013 08:59 AM

RE: One flick starts, is this a myth?
 
My most reliable one flip diesel is a Rustler Cheetah. Prime the piston side, choke once, flip, turn the compression back 1/2turn and fly. I use a starter quite a bit otherwise. I like to leave the engine set at running setting, which is generally undercompressed for easy flip starting. People flying stunt with diesels have complained of unreliable running times. I think this is a result of fiddling with the needle to get a start. On some diesels, a finger choke may be necessary to keep it going initially with the needle at the running setting.

Jetdesign 03-14-2013 10:19 AM

RE: One flick starts, is this a myth?
 
O.S. Engines

Mr Cox 03-14-2013 12:47 PM

RE: One flick starts, is this a myth?
 

Quote:

ORIGINAL: gaRCfield

O.S. Engines
The electric ones?


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