RE: Inverted engines
 

Stick Jammer, indeliberately or deliberately to justify your own rational, you've taken what I said out of context. Read it again.

One can always correct a fuel tank engine feed relationship if one wants to. If its resultant of poor design as you mention yours is, then its a flaw in the first place which raises the question of how many others are designed/inbuilt into the model?

Exacerbated by tank volume and shape, unless running on pressure or injection, severe inequity in the median fuel and carb intake levels will result in impossibility of setting an optimum tune needle valve setting which will remain relatively consistant over the duration of the tank and entire aerobatic flight envelope.

You've mentioned the patch/ersatz approach in using a ball valve. This doesn't address the root cause. It's one of several available workarounds. If you're gonna' do that, why waste money on the unnecessary complication of a ball valve? Just use the pinch method. Cowled engine I suspect. :)


That's a big if full of far to many "subject to" caveats for the beginner or any person needing to ask the question. Bottom line is that for the average flyer unaware even of what hydraulic locking is these days and using an electic starter, under the circumstances described, there's an inevitibility that at some time he will attempt to continue cranking when its hydraulically locked. Can you say "bent or broken rod" with a four stroke?

Now you're taking the absurd extreme for the sake of trying to justify the argument you present, but which in fact weakens it relative to the context of the case in point. You know the circumstances I'm referring to, and increased probability under those circumstances described.

The best way to avoid engine damage is to not use an electric starter at all. Not only are they unnecessary, but it's largely because of the electric starters becoming another marketing opportunity and fashion accessory that far too many contemporary R/C fliers lack even basic mechanical knowledge and engine management skills needing sage advice on such matters as these.

As for the rest of your post, the subject under discussion was a case of extreme flooding attributable to setup. Of course you can flood any engine if you deliberately try, and some even manage it without deliberation. But in normal ops, it's not an issue nor is there risk of hydraulic locking except for cranky starting engines usually due to the owners poor engine handling skills, and wankers who don't realise something is wrong when it doesn't bust into life within seconds as it should, but continue cranking away continuously for 30-60 seconds accompanied by the ubiquitious cursing and swearing as if it was actually the engine's fault! Doesn't do the electric starter a lot of good either.

RE: Inverted engines
 

Give some thought to the possibility of mounting the engine as a sidewinder at either 225, 270 or 315 degrees with the new cowl if it will advantage the carb fuel level alignment without necessitating major surgery. Just as upright, rotating to 270 should raise the intake a little and won't affect the cowl/spinner alignment. If you precision cut the cowl, at 225 or 270 it will not only look every bit as good as an inverted engine, but reduce or eliminate the easier to flood starting disadvantage of the inverted mount engine. It will mean drilling new holes in the firewall and pluging the old, but compare the task to aligning the fuel tank height.

You're the right track. Just get that median fuel tank level aligned +/- ½in with carb inlet and spend your time at the field enjoying your flying with confidence rather than constantly fiddling with an impossible to set right needle valve, cursing the rich run and lack of power after take-off and for the first ¼ of the flight and either landing and re-adjusting mid-flight when it goes lean or be constantly replacing prematurely dying plugs from the excessively lean end-run.

RE: Inverted engines
 

sigrun,

It wasn't my intention but I seem to have ruffled your feathers simply because I mentioned that this initial statement isn't true.

Though some may exist, I haven't seen a model yet that is perfect in every way.

Point taken, BUT, there are many things about this hobby that one must constantly be aware of, most of them safety orientated.

I've seen a few new comers flood an engine, (with the carb/tank correct), to the point of hydraulic lock simply by over-priming when it failed to start.

Personally, I feel an electric starter is probably the safest method for beginners as well as the easiest. Flip starting can be very frustrating until they have more experience with tuning an engine.

To reiterate, I wasn't trying to rattle your cage. I simply thought it was worth mentioning that I own and fly a plane that fits this scenario exactly and though it may take a little more effort at start-up, it performs beautifully. I'm not saying that every one who tries this will have the same success, but it can in fact work.