Gassers-Do They Have to Be Inverted?
 

I have a scartch built 1/4 Scale Fokker D-VII that was previeously powered by a ST-3000. That engine was installed in a straight up configuration. I was looking at powering it with a CRRC 40 that I can get from Abell RC for $150 (new in the box). I've seen several "YouTube" videos on this engine and they all looked pretty good. The dimensions would allow me to mount it straight up where the only adaptation would be for a cut out for the velocity stack. Is it okay to mount a gasser in a non-inverted position or do I need to adapt the bottom of the engine compartment for an inverted install? Thanks for your opinions and suggestions.

Happy Flying

Loopman ;)

RE: Gassers-Do They Have to Be Inverted?
 

Mount it anyway you want. they will run the same in any position

RE: Gassers-Do They Have to Be Inverted?
 

Loopman,

I owned a CRRC 40 engine at one time. A couple of pointers. Make sure you change the plug out to a NGK BPMR6F plug. Also the stock ignitions can be hit or miss, so you might want to look at getting a Rcxel ignition. Good little engine. Would turn a Mejzlik 20X8 at around 7000 RPM.

http://www.rcuniverse.com/forum/m_77..._1/key_/tm.htm

RE: Gassers-Do They Have to Be Inverted?
 

The worst engine position is inverted. If primed too much, all fuel and oil residue will puddle in the spark plug.
ALL other positions are better.

RE: Gassers-Do They Have to Be Inverted?
 

I agree 100% with Pe's post. ALL positions are better than inverted for gassers. That's NOT to say they don't work inverted, it's just SOOOOOO easy to flood them. All of mine are inverted but only because of the cowl and how nasty it would look with a big cylinder sticking out the side or top. LOL
Also, helodrvr had some excellent points on the quality of the ignition components supplied.

RE: Gassers-Do They Have to Be Inverted?
 

Gas engines or SI engines (SI- spark ignition) dont burn petron- in the liguid form that is. Liquid petrol doesnt burn. In the carb, the petrol is sucked in and as it moves to the cylinder, it changes to a gas (its very volatile). It is this gas-air mixture that burns. So, theoretically, gas engines should work in any position

Ameyam

RE: Gassers-Do They Have to Be Inverted?
 

I have read that a engine mounted at a 45 degree angle will transmit a little less vibes too the airframe and control surfaces. Also it may help make it more easy tooinstall some exhaust systems. Capt,n</p>

RE: Gassers-Do They Have to Be Inverted?
 

This is great advice. I will definitely change the ignition to an RCEXL one along with a new Hall's sensor and an adapter so I can use a CM6 plug, these are available from AGAPE RC Racing out of Virginia.

Happy Flying!

Loopman :D

RE: Gassers-Do They Have to Be Inverted?
 

Given the fact you have a nice scale plane with a lot of hours into it I would replace the stock bearing for Boca Berings. China bearings just are not as good.

RE: Gassers-Do They Have to Be Inverted?
 

agree here, but I also never prime the engine with the ignition off. ign on prime till it fires, ign off and it will run. you need to get to know the engine though, some do like things differently

RE: Gassers-Do They Have to Be Inverted?
 

Inverted may not be the best position but it certainly does not hurt a gasser.<div>
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RE: Gassers-Do They Have to Be Inverted?
 

Agreed!

If you have your eng correctly tuned & ign ON, choke it, get it to pop, choke off, start & go fly!
Flooding due to being inverted is no big issue, everybody's done it & we all know why (but won't share our dumb moments):(

Gassers don't know nuffin about up -or- down, just fuel/air/ign.[sm=thumbs_up.gif]

RE: Gassers-Do They Have to Be Inverted?
 

If inverted, always use a starter or atleast a chicken stick. Atleast I do. Dont ask me how I know

Ameyam

RE: Gassers-Do They Have to Be Inverted?
 

And when starting any engine, if you're wearing a coat or jacket, zip it up! Ever have a prop tip get caught in your jacket pocket? I have. I was leaning over the engine which was on a low test stand and immediately found myself on my left knee with my face but a few mere inches from the spinning prop. I'm not that good looking to begin with and I really don't have any room for further degredation.


Ed, NM2K

RE: Gassers-Do They Have to Be Inverted?
 

Watch the tie string if you have a hat with a string around your chin, to keep it on in windy weather, and the dangling bits are long enough to get tangled with the propellor. I've long since cut mine short, but sometimes wondered what it would be like getting your head dragged toward the prop as the engine fires up and the string gets tangled in the spinning prop....

RE: Gassers-Do They Have to Be Inverted?
 

Tramsmitter neck straps are another thing to dangle in the prop.Put the hook and buckle down the front of your shirt while starting.
BCCHI

RE: Gassers-Do They Have to Be Inverted?
 

And neck straps that are detachable, while convienient, can still be a problem. Tuck the short (neck) portion in your shirt when starting, THEN when ready for t/o connect the longer portion to your tx.

RE: Gassers-Do They Have to Be Inverted?
 

Also you are much better off with a bow tie than the normal style.

As the others have said the engine will run fine mounted in any direction. My Grosse Biene has the engine mounted upright and the only thing that had to be done was solder a brass tube over the metering diaphragm plate and run the breather tube into the fuselage. But a rear carb engine would probably not suffer the same problem.

Jaz<br type="_moz" />