XpastywhiteboyX

My Feedback: (5)

i got a 50cc gasser converted to glow. (i know this should probably go in teh glow section) but i need people with knoledge : ) (not that glow people arnt smart i just need people who know gassers) anyway it had 2 glow plugs and one was right where the spark plug was. and one at a 45 degree angle. the one at a 45 degree angle shot out. must not have been taped out right. i really wana just plug the hole with a bolt and use the 1 glow plug.....people at my field said 2 plugs arnt nessissary. so i wanted some expertise on the subject. this motor is rad it will run full throttle backwards. i need a variable pitch prop so on a downline i can back it up : ) thx so much guys. john

w8ye

My Feedback: (16)

First of all a glow plug hole is Tapped 1/4"-32 and you are not going to find a bolt with those thread deminsions. Stick a glow plug in the hole and it will self ignite when the engine runs or if you do not care, just use a old burned out plug.

A gas engine converted to glow usually has a pretty good 4 cycle to 2 cycle transitional difference. If the engine is set mixture wise to where it runs at the high end of the 4 cycle point, then when you start up in a loop, for example, it will break into 2 cycle mode and have more power. On the the down side of the loop, it will convert back to the 4 cycle mode and offer you a breaking ability. It's almost like having a automatic throttle on the engine.

This engine will do better with FAI type no-nitro type fuel.

At least all these parametrers are what I have noticed with the guys using the Zenoah G23 glow engine.

Enjoy,

Jim

XpastywhiteboyX

My Feedback: (5)

thank you i think i might put a heli coil in it and keep both plugs. what do you think about that?

w8ye

My Feedback: (16)

It will be difficult to find a 1/4"-32 Helicoil. When you do, you will have to buy a bunch of them and the cost will be out of the question.

There is a guy by the name of Clarence Lee who can put a Helicoil in it for you but you will have to send him the jug or the whole engine to get it replaced. You will have to pay the shipping both ways plus the installation of the Helicoil.

Do a search on here for Clarence Lee to get his Address or Number. You might try Helicoil or 1/4-32 also?

Enjoy,

Jim

Kris^

My Feedback: (1)

If you want to just plug the hole, a 5/16-24 tap will work perfectly with a stripped 1/4" hole, then you can use a very short 5/16 bolt and JB weld the threads when you insert it and use a flat copper gasket (like for brake lines on a car. . available at NAPA) under the bolt head to affect a guaranteed seal. I doubt it will ever leak after that. Make sure the end of the bolt is flush with the inside of the combustion chamber so that accidental contact with the piston does not occur.

Antique

My Feedback: (4)

You will need to make the carb pass more fuel..I drill out the main inlet needle hole to .083, the 3 small holes under the welch plug to twice the AREA, not diameter...You can make a better taper on the low and high speed needles, but the seats for those will most likely be big enough...A gas carb converted this works exactly like it did on gas, but the low and high speed needles will probably be set at a different place..If you can't get it rich enough after these mods you can enlarge the hig and low speed needle seat holes a little at a time until it works right...Easy does it, they're just aluminum....It takes a set of number drills from #61 to #80 to do it right....

DKjens

My Feedback: (50)

Just out of curiosity. If plugging a glow plug hole in an aluminum head with a steel bolt, what are the chances that this bolt will create a hot spot, which can pre-ignite the fuel. I know this could be a problem if running gas, since this as alcohol, it may need moore than heat to ignite, I'd like to know.
DKjens

Antique

My Feedback: (4)

Could not possibly get as hot as the element in the glow plug, not a problem....
The glow plug is made of steel, when the element burns out the engine stops...
I built a race engine with 4 extra glow plugs in each head..The whole center of the middle glow plug got blown out, the other 4 were still hot, the heat from the combustion melted the steel housing of the open glow plug just like a cutting torch...

XpastywhiteboyX

My Feedback: (5)

wow thx guys for the info. so do i need the extra carb hole or no? this is gunna be interesting il keep you posted on how the enguine runs. i need a 5/16? im not putting in a heli coil. what size do i need tap it out to if im just putting in a short bolt? thx guys. john