Hello - I just got my new filter head and there are 2 1/8" NPT ports on either side that I'd like to put glow plugs into. However I have only about 3/4" room inside the filter head. I believe it's possible to grind down the glow plugs to make the heating element shorter, but I was wondering if anyone can tell me what effect this has on the performance. (do they get hotter? not as hot, need more current, less, etc)

thanks
as always
peace and love
billyO

not sure if you can grind down a glow plug however you may want to look at this link



Electrical Heat

An electrical heating element can be used to heat up the oil to suitable temperatures. In a vehicle application care has to be taken not to have a power demand that would be excessive for a given electrical system. Rapid heating is possible with an electric heater allowing a dual fuel system fuel supply to be switched sooner. A suitably modified engine equipped with electrical heaters can be started and run on SVO alone.

more info here
http://vegburner.co.uk/heat.htm

have a good read
Omar


or you can look at the heated wvo filter link

You will need to use a spacer or put them in a TEE before the filter . I recommend using 24v GM (military Hummer) glow plugs on 12V . Search for posts on glow plug heaters .

Just check it's resitance before and after grinding. If it's the same, it should be ok.
But with reduced surface area to dissipate the heat, I would guess it will get hotter than stock.

No, you cannot grind down glow plugs.

My opinion also, NO, the tip is only a somewhat thin outer sheath, the actual resistance heating element is located inside the very tip as can be seen by the white hot end shown in the prior picture.

I am using the standard GM self limiting glow plugs, they are rated as 12 volt units in the vehicle but if you wire two in series you get half the total heat and each one puts out 1/4 there max heat, they will last for about forever at this low heat and are much less likely to toast the oil into crispy chunks that can get passes on with the oil. Powering one with a cheap 15 or more amp PWM DC motor speed control will allow you to make any amount of heat from none to max with the turn of a knob.

If you have the room you might bore out the 2 openings, thread them for 1/4 inch pipe and screw in 1/4 to 1/8 pipe bushings, this will move the GP out something like 3/8 of an inch, did this to add electric heat to a Suntec oil burner pump once.

Even dropping a glow plug on the tip will render it useless. However you could probably find a different sized plug to do the trick.