Make small glow plug for diesel engine : Is it possible ?

[minh-thanh]

Hi All !
I intend to make small glow plug for diesel engine
Do you think is possible ?
Any comments are welcome !
Thanks .

 

[stevehuckss396]

Search for glow plug. I think there are a few threads with folks making them.

 

[SmithDoor]

I agree

Dave

Search for glow plug. I think there are a few threads with folks making them.

 

[minh-thanh]

Hi !
Yes I did a search, but I can't find the exact type I need as shown in the picture, or am I searching the wrong way ?

 

[stevehuckss396]

Sorry I was not thinking you wanted an exact copy except smaller. I guess the answer is maybe. Depends on how small and how good your skills are. Myself maybe not. Jerry Kieffer absolutely and it would work very well. If it gets too small the wire might get too small and burn out easily. If it stays about the same size as an RC glow plug then it is very possible.

Sorry but I cannot remember where I saw the glowplug making. It may have been in Strictly IC or model engine builder magazine. Darn I thought it was online. A google search came up with nothing?

 

[bluejets]

Englishman George Luhrs used to make some incredibly small engines and components including small glow plugs.
Other than that we used to use glow inserts on rc pylon racing engines.
Most model diesels dont use a plug, just ether, kero and castor oil.

 

[Mechanicboy]

The early glow plug had the glow spiral to heat up and start the cold diesel engine. Maybe easier to make the glow spiral instead the difficulties to make the glow plug with hear elements inside.

 

[minh-thanh]

steve !

. If it gets too small the wire might get too small and burn out easily. If it stays about the same size as an RC glow plug then it is very possible.
Sorry but I cannot remember where I saw the glowplug making. It may have been in Strictly IC or model engine builder magazine. Darn I thought it was online. A google search came up with nothing?

That's something I haven't thought of
Thank you !
Yes, I searched on google but nothing.


Mechanicboy !
Yes I have seen the same type on google
It's a style that seems easier to do, as well as easy to replace the resistor when it fails, but it seems like it will increase the volume of the combustion chamber.
my intention make the glow plug with heat elements inside, but it seems it's too small....

 

[petertha]

I'm drawing a blank too. But the micro glow plugs I recall were made from harvesting the (apparently near unobtanium high platinum %) wire from a commercial plug & managed to spot weld onto a new body a fraction of the size. I seem to recall the welding was a bit of trial & error too with a few R&D casualties. So by keeping the glow wire essentially the same but packaged differently, they were able to get similar running characteristics on same fuel, CR etc. & use similar voltage & current for the igniter. I don't understand the catalytic effect myself, but obviously the wrong wire could be more damaging to the engine if it burns & fragments. Commercial glow plugs 'go dead' & the engine doesn't run, but its a rarer bad day that they shed fragments & cause damage.

 

[minh-thanh]

petertha !

but obviously the wrong wire could be more damaging to the engine if it burns & fragments. Commercial glow plugs 'go dead' & the engine doesn't run, but its a rarer bad day that they shed fragments & cause damage.

This is very easy to happen with my homemade glow plug

 

[Gedeon Spilett]

If I understand, you are looking at a preheating plug for diesel engine to ease the cold start, rather than a glow plug for ignition in a RC engines ?

 

[minh-thanh]

Gedeon !

a preheating plug for diesel engine to ease the cold start,

Yes .
I want to try , and then try it with my diesel engine, and find out if it makes any difference ( although my diesel engine runs easily at room temperature )
Just a plan...
There are a few things I need to think about

 

[Mechanicboy]

If difficulty to make a tiny glow plug, use hot bolt to screw on cylinder head after the bolt is heated by torch lamp then start up the diesel engine. The hot bolt has a thin and long bolt who are heated up first with torch lamp before screw into the cylinder head before start up. Or the second alternative as the picture are showing ..

 

[ranger]

Some full size diesels used an exposed element glow plug mounted in the inlet manifold to heat the air in the manifold, rather than inside the cylinder itself. Could you perhaps fit a suitable ‘resistance wire’ element loop across / through the manifold close to the opening, insulated at one end, with the electrical connection, and grounded to manifold at the other? This should be less obtrusive, visually, than an ‘over scale’ plug on a miniature engine. This would also be less susceptible to damage than if inside the cylinder. For test purposes, install the ‘element’ in a short piece of hose to fit over the inlet, before drilling holes, in case it’s unsuccessful.

 

[minh-thanh]

If difficulty to make a tiny glow plug, use hot bolt to screw on cylinder head after the bolt is heated by torch lamp then start up the diesel engine. The hot bolt has a thin and long bolt who are heated up first with torch lamp before screw into the cylinder head before start up. Or the second alternative as the picture are showing ..View attachment 134841

Although, it's only for "research" purposes ( sounds like a savant ) but I like to make it a bit good .
Thanks !

Some full size diesels used an exposed element glow plug mounted in the inlet manifold to heat the air in the manifold, rather than inside the cylinder itself. Could you perhaps fit a suitable ‘resistance wire’ element loop across / through the manifold close to the opening, insulated at one end, with the electrical connection, and grounded to manifold at the other? This should be less obtrusive, visually, than an ‘over scale’ plug on a miniature engine. This would also be less susceptible to damage than if inside the cylinder. For test purposes, install the ‘element’ in a short piece of hose to fit over the inlet, before drilling holes, in case it’s unsuccessful.

That idea seems to be the best and fits my cylinder head ( it's too small )
Just change and make a new inlet manifold, install the resistor wire
If necessary, add a timer circuit .
Thanks for your opinion !!

 

[Mechanicboy]

Although, it's only for "research" purposes ( sounds like a savant ) but I like to make it a bit good .
Thanks !

Minh-Thanh,..

The hot bolt has been used in the diesel engine where battery/glow plug was not available to example i rural areal and in fishing boat.

 

[Mechanicboy]

Minh-Thanh.. The other picture..

 

[minh-thanh]

Mechanicboy !
Thank you !
The problem is :
My cylinder head is too small and it's too difficult to install a glow plug or hot bolt , If I add a glow plug or hot bolt I will have to make a new cylinder head...
I think ranger's opinion is the best.

 

[Mechanicboy]

Mechanicboy !
Thank you !
The problem is :
My cylinder head is too small and it's too difficult to install a glow plug or hot bolt , If I add a glow plug or hot bolt I will have to make a new cylinder head...
I think ranger's opinion is the best.

The heated air in the manifold by glow spiral works very well too. My father had the truck with diesel engine who had injector with glow spiral mounted on manifold to ignite the dieselfuel spray then the cold air quickly heated up to hot air by flame and sucked into the cylinder under starting.

 

[Mechanicboy]

Flame heater in operation..