pe reivers

prime priority for my next big-un is an engine driven on board power generator and water cooling with electric water pump. This should be a fully grown up self supporting system, no fuss with charging, just fuel up and fly. Not for you funny 3D guys though, You still seem too busy counting ounce fractions

About engine starting, and the best way (back on topic!)
Cold engines need a bit more gas, because only part of it evaporates, and the rest condenses on the cold engine surfaces. That is why rich idles start easier.
If you set your carb for hot running, with lean (er) idle, cold starts will suffer, and the full choke hot start is the surest thing for you!
With on board choke management, like reported, life gets easier.
With the new MVVS system, what else do you want, because the engine governs the choke servo!
Electronics seem to have made it their purpose in life to take over where normal mortals fail. I think that is a pity. Many will not agree with me (I know), and think it is a blessing.

rmh

Having watched that auto choke many times - No thanks
the theory is fine -in actual execution not fine - too easy to get it wrong
that and the momentary spark which turned the prop - were to me - two of MVVS less than shining moments.

cyclops2

That is why I only buy boats with a 2 bbl carburator. I can at least tie a shirt over the inlet to get a rich enough mixture at 1 speed to limp home if necessary. Can not touch the Thunderbolt II ignition.

How did I singe a wallet over a carburator ?

Rich

Am I for real ?

mrbigg

My Feedback: (21)

Speaking of watercooling, I did a search for a ZDZ 80 a while back and found a site where a guy made one liquid cooled.

pe reivers

A while ago, before MVVS made their LC 58, I made two LC 26cc MVVS engines for a customer's boats. Turned the ribs off, made a new button head and a cooling jacket that held the button down. Never heard of it again, so I hope no news is good news.

karolh

Just for the hell of it I just tried the "other" starting method, that of choke on but without the ignition on, and was rewarded for my efforts by flooding the engine. Of course as several of us have found out, removing the cap on a CM-6 plug can at times be challenging and this time was no different. Pulling the plug I found it filled to the brim with gas.

Wiping it dry and replacing it after a few smart spins of the prop had cleared the cylinder, and using the tried and proven start technique, I had the engine going in no time. So much for my trying to re-invent that wheel.

Karol

pe reivers

That proves the cold choke method (cold=no ignition power) is about the worst method to choose, unless you know exactly how much you need to choke.

RTK

My Feedback: (1)

You can't flood them with the ignition on choke method, or at least I can't. I use the KISS principle

Bob Pastorello

My Feedback: (198)

Yep. See post http://www.rcuniverse.com/forum/fb.asp?m=7101853

RTK

My Feedback: (1)

Did I miss something Bob? Consensus being: ignition on, choke on, flip till pop, choke off, flip until start. I have never flooded a piston port or reed valve engine that way. I assume rotary valve would be the same, but I do not own one yet.

Bob Pastorello

My Feedback: (198)

Not at all!!! I was reminding us that TKG had posted that already, and the consensus was it was correct......I'm so confused...........which end do I put the prop on, anyway?

RTK

My Feedback: (1)

Not giving you any heat Bob, I did not know what you were refering to and I didn't remember I posted already. I guess age is creeping up on me.

Bob Pastorello

My Feedback: (198)

You three initial guys!!!!!!!! Now I'm getting confused.... it wasn't you.... that other three letter guy..... anyway, I think we're all agreeing. We should party.

ram3500-RCU

My Feedback: (221)

OK, nothing fancy here. Works every time, on every gas engine I have and I have a CRRC and a Thor among others (I don't fly DA and I've been told they don't like to be wet like other engine do).

1. switch on
2.choke on full
3.throttle full on
4.pull through compression till it starts then dies
5.choke off
6.throttle set to idle
7.3 or 4 props and it will be running

let it warm up then check transition and go fly

Bob Pastorello

My Feedback: (198)

SURELY item # 3 is in error???? Starting at full throttle is a really scary proposition.

ram3500-RCU

My Feedback: (221)

No error. She doesn't go anywhere with full choke. It gets the fuel flowing quickly and just as quickly chokes out. It never builds to anywhere close to maximum RPM (usually a few revs is all you get with all that choke). A couple more flips with the choke off and the throttle at idle, and she starts easily with plenty of lube. Everyone I know, that has been flying gas for any time, uses this procedure with 100% results and no issues. As always with these monsters, our planes are either held securely by another guy who knows what he is doing and won't be spooked when it fires, or tethered securely. No plane should be started unless these safety steps are taken.

Rcpilot

My Feedback: (78)

I will sometimes choke and flip with the throttle wide open. It starts and runs for 1/2 second and then dies. Now turn the choke off and throttle to idle. Flip Flip.

I also put my choke on a servo. I use the gear switch to work it. You just have to know how to actually set up a linkage to do it right. Any idiot can hook up a pushrod to a servo and run it to the choke. Not EXACTLY what you want to do though.

You want the servo endpoint at 0 when the choke is open/off. That way, while you're flying the plane, that servo is just sitting there. No load. The only time that servo is loaded is when you are choking the engine. With an endpoint setting of 0 -- the servo will just sit there. No buzzing or groaning. No load on the battery.

I've seen guys hook up a choke servo and adjust the endpoints to make it work perfect, but the servo is groaning the entire time the switch is turned on. Thats because he didn't set it up right and he's using an endpoint value other than 0 when his choke is fully open. Wrong. Wrong. Wrong. But he's proud as punch 'cause he gots a switch for his choke servo.

Bob Pastorello

My Feedback: (198)

Interesting.
Everyone that I know starts at "high idle", and that works 100% of the time.
Just proves that there are a variety of ways to make the prop turn.

rmh

I use a low idle really it makes for a richer mix.

JoeAirPort

My Feedback: (41)

My post is in response to the first post, if anyone remembers what he was asking. If anyone was having luck with starting the engine at half choke instead of choke off for the starting flip? For my ZDZ 50 NG, since I like my low needle leaner for good performance, I need to start with a partial choke just like my new Toro 153cc 2-stroke snow blower. I almost burned out my shoulder using the normal starting method. Then I tried leaving the choke cracked open, and it would fire right up and stay running. I let it warm up for a about 5 seconds like that and open the choke while it's running. Works great especially in spring/fall/winter. So yes, partial choke works great for a leaner low needle. Why set your low needle rich only for starting? Set it for flying and use the choke to richen the mixture while it's warming up.

For some reason this hobby doesn't use the choke for cold starting. They use it only for priming. All the other industries use the choke for cold starting, even the aviation (before fuel injection). The priming bulb is for priming. The choke is for starting the engine and keeping it running while it's cold. The needles are set for an engine that's up to running termperature, not to facilitate a cold start.

PS: Dick, I agree with the low idle comment. Since these carbs get richer as you throttle down through the midrange down to idle, that totally makes sense and I need to do that instead of a high idle, it's safer too.

Robotech

My Feedback: (9)

That's the exact sequence I use on my DA 100 minus step #3. I realize that it will draw the fuel and fire off faster with the throttle wide open but due to my forgetfullness and and propensity to injure myself it's not worth the risk of forgetting to return the throttle to idle. I did this once with a person holding the plane rather than using our starting posts and scared the *#&$ out of the both of us. [X(] Now had he been a smaller fellow or not paying attention ( as I was not ) some one (me) could have been eaten alive.

ram3500-RCU

My Feedback: (221)

It is probably best to use a procedure both that works and one that you are comfortable with. Personally, I am comfortable with and strictly adhere to this procedure. I always follow the same steps to keep from forgetting to, for instance, close the choke. However, on a cold engine, you would flip and flip with no hint of firing in this configuration, if the choke was open all the way, a tip something is amiss. These steps have my cold engines running in 4-6 flips total, always. As noted already, the engine simply will not run more than a second or two fully choked. If it does, you have other problems, but in any event, it will not make power. More that one way to skin a cat, if your into cat skinning, or, start an engine.

Jake Ruddy

My Feedback: (40)

Exact same method I use.. works like a charm. I don't think it gets anymore rpm than if you did it at half throttle or whatever.. it only stays running for a couple turns and dies.

JoeAirPort

My Feedback: (41)

As I said on cold mornings that normal procedure will take many flips and re-chokes....if you like your low end lean like I do. I found that the partial choke gets it running right away on even the coldest winter days. As was mentioned, many ways to skin a cat. But you better have that low needle pretty fat if you want to start on a cold spring, fall, or winter day....with that choke fully open. Then you're stuck with a fat mid range once it warms up, no fun.

ram3500-RCU

My Feedback: (221)

I don't see this issue on my engines Joe. After they are warm, I adjust them for proper idle, midrange, transition, and high end (sometimes a tedious procedure to get it all right), but after all this is set, it is usually set for the season, and my starting procedure works great, any engine, cold or not so cold, no restarts, and no flipping and flipping, regardless of needle settings. I feel the choke is there to get things flowing and once they do, the settings in the carb take over, whatever they are for that particular engine. As I said, if it doesn't start right away, or doesn't stay running, it is because something is wrong, and I start looking. Some of my engines like a leaner low end, like my 3Ws, but I don't start them any different and the start just like all the rest.