Sacagawea

just wondering how rc airplane engines explode?

Charlie P.

Timing gets off (using too much nitro or an overly long plug that raises compression) and it fires as the piston is still rising. Something has to give. If not the rod or the wrist pin then the head or the cylinder.

TexasAirBoss

My Feedback: (22)

IF the engine gets to hot, the fuel/air mixture can explode below the piston. Its called detonation. It generally bends the heck out of the wrist pin. Then at some point the pushrod and wrist pin part company. Either the pin breaks completely or the end of the rod does, or both. Metal peices inside the engine will scar the sleeve and might jam in places. Things go quiet, and you notice your prop is windmilling. Sometimes the engine can be rebuilt with only a new wrist pin and pushrod, often the inards are too badly scarred. It all happens inside. You generally don't see a hole in the case. Parts don't come shooting out of your engine. Every now and then , you might see a hole in the case when the bottom end of the pushrod fails and the last stroke pushes the rod through the bottom or side, but thats really rare.

jetmech05

running too lean

Scar

My Feedback: (3)

I've never seen one explode.

Were you asking about ignition? Glow engines ignite the charge catalytically. The glow plug element is a catalyst, and the alcohol in the glow fuel reacts & burns.

Good luck,
Dave Olson

rcdude7

My Feedback: (264)

I don't know, never seen or heard of one exploding. I have seen crankcase failure, the engine quit running but did not explode.

The worst damage I have ever seen was a RCS 30cc run into a tree trunk at full throttle, full speed. The engine was a total loss, junk.

ho2zoo

My Feedback: (5)

I always wondered if a glow engine would explode if you tried to run gasoline in it... [sm=50_50.gif][sm=72_72.gif][sm=confused.gif]

Don M.

My Feedback: (5)

If you read between the lines I believe he is asking about the combustion process. Post #5 answers the questions. "Explode" IMHO was just a poor choice of words.

Tommygun

My Feedback: (2)

I always wondered what it would do too; does anyone know?

Tall Paul

Sounds like a question from one of the children infesting "Mythbusters", who have a fixation with "exploding" things.
It doesn't happen with model engines.

Tired Old Man

My Feedback: (1)

Glow engines can be converted to run gas by changing the carb and plug, so they won't explode by using gas. A perfect example is the BME 90 conversion. An Enya 4 stroke was converted to run gas and crossed the Altantic non stop in 1999 I believe. No explosions with that one either.

ho2zoo

My Feedback: (5)

It's not about enjoying "expoding" things, (which I do, BTW) and we're not talking about engines that have been converted to run gas. We're talking about a standard, stock glow engine being fed some ordinary gasoline. As we all know, gasoline is much more volatile than glow fuel. So when the gasoline hits the hot glowplug element...????????[sm=50_50.gif][sm=72_72.gif][sm=confused_smile.gif]

Scar

My Feedback: (3)

There is a thread in one of the engine forums, about running glow engines on a mixture of gasoline and glow fuel - with a glow plug. I think the title is Gas / glow or something like that. If you want to hear about RUNNING an engine with glow and gas, with a glow plug, look there.

That's the best I can suggest.
Dave Olson

rcdude7

My Feedback: (264)

Gasoline is much more volatile than glow fuel. So when the gasoline hits the hot glowplug element..............?????????????

Nothing happens.............

Glow fuel works with a glow plug because a CHEMICAL REACTION occurs between the metanol and platinum glow plug element. There is no such reaction with gasoline.

Would be nice if it worked, we'd have given up on alcohol years ago Never the less, my engines are still alcoholics today because they can't live without.

JPMacG

My Feedback: (2)

There is an engine in my collection that I would like to see explode. Just tossing it in the trash is not satisfying.

KI8FR

If you put gas in a glow engine it will run untill you take off the baterie. There is no methenal in gas to keep the engine running. I have alot of engines that I run on what we call gas/glow. We mix 2:1 gas and glow fuel. 2 parts gas 1 part glow. Works grate. but it will not work with a small gow engine. Needs to much oil. The engine need needle berrings. but a gow engine will run on gas just fine. You would have to put alot of oil in it to keep the bussings on the rod there. but Like I said with out glow fuel the glow plag will not stay lit.

I love my gas/glow engines.

bluestratos

I had a 4 stroke explode in flight, after about 20 hours of run time. The entire cylinder parted company from the case, taking with it the piston, crank and carb. All that was left was the bottom of the case, still mounted to the engine mount. The cylinder parted so violently that blew the cowling to bits in flight and of course the plane became very tail heavy suddenly. I landed it as it roller coastered to the runway, lol..

Randy

thewrap

Under right conditions it can happen. I saw a friends Saito 60 twin blow up, very spectacualar but very dangerous. I think we determined that there was a problem with the timing and an overload of prop. It binded up then when it went to unload it just blew up. Cracked right at the crackshaft. The plane came out okay but the motor was in about 30 pieces.

Sacagawea

I'm not talking about how the whole ignition and combustion thing works, I'm talking explode as in ''BOOM''. Just watch, its pretty cool.

http://www.youtube.com/watch?v=S0jDFTldGHY

http://www.youtube.com/watch?v=OeTDaWf6fps

If for some reason the link does not work just type in ''RC Airplane Explosion'' on youtube.

And about running your engines on gasoline (with the 2-stroke engine oil) i'm pretty sure it would work, you would just need to run the engine fairly lean because gasoline has higher potential energy than methanol so it has a more powerful explosion, plus your engine would probably run alot hotter even with 2-stroke oil because gasoline does not have as fast evaporation rate as methanol so the engine could not ''sweat'' the heat off as well, but it would be neat to see someone try it.

TexasAirBoss

My Feedback: (22)

That was done with an M-80, an Estes igniter, a battery and a micro switch.