I've got a manual switch for my glowplugs, i dont want to burn them up, how long do i need them on for starting first time, and after its warm?...Edited by: savvy-R

After it's warm you won't need them. Only cycle them if the truck won't start.


Which model plugs do you have? I run the AC 60g's and they are not suppose to burn up, I run them about 10 seconds.

I Wouldnt recommend it , before i bought my 1987 1 ton 6.2 the guy had a push button , Id just by the glow plug relay the glow plugs tend to blow up and can mushroom the end so you end up having to pull the heads off...

Gene Gritner

10 seconds and you'll fry the plugs. New Delphi plugs glow red in 4 to 6 seconds.

I read somewhere they actually test the AC-60gs for over a minute and didnt burn them out. The best thing I did to help mine start was to put a push button switch with a ford starter solenoid and add the 60gs. I hold mine for about 10 seconds and it always starts right up. Even after sitting for 2 months in the winter it started right up.

the first thing you know is you lose 1 of 8 glow plug's the truck start's fine, glow plug's burn out , the person never services there truck , glow plug's should be checked at 20,ooo mile interval's , but never are , sone you have 4 of 8 burned out and you think your controller is not working , so you get out your home wiring kit and you wire in a switch , leave the glow plug's on 10-20 seconds 4 of 8 are still burned out but they cost 20.oo each so your cheap and wont cure the problem , you end up mushrooming the end of a 60g glow plug , they were never intended on staying on for more then 10-15 second's , and by then they are hot ! RED HOT
man. plug and you leave them on 20-40 seconds and they are gone . I find that the best glow plugs for anything is stock oem gmc 60g's , napa makes them and they are cheaper , they dont last as long and dont get as hot .
mushroom the end of a 60G and YOU WILL HAVE TO pull the head whats that worth ? 600.00-1000.00 if you do it right , new anti freeze , thermostat , have the engine timed at gm, gasket's , labour .....

Doug Gritner
Doug's Repair
Alexis Creek
British Columbia
250-394-4578

The 60G's do not mushroom the tips!!!! The 60G's don't heat up as fast (maybe 40-50 percent as fast). In the summer (90 degrees) I leave the plugs on for 10 seconds and in the winter 20 + seconds. I know the Champion plugs and the original GM glow plugs will mushroom the tips, but I used them for over 100K miles and never had a problem. I changed to the 60G's so I wouldn't have the risk of mushroomedd tips.

I run my glow plug solenoid control wire thru the temperature thermostat controller on the right bank. If the engine is warm then the controller points open so the solenoid will not close. I by-passed my glow plug controller over 100K miles ago.

heh, petrols... the truck had the manual switch when i bought it........just checkin..

I've been using the same set of 60Gs for a few years, wired to a manual switch. I engage them for around 5 seconds during the summer and in the winter I engage them for 15-20 seconds. 20K miles and 3 winters later I am still on the same set of glow plugs. I tested all of them a couple of months ago, they were all still working.

I have hooked a 60G plug to a battery and let it glow for around a minute, no burn out and no mushrooming. And that was one of the plugs currently in my truck.

I really like these plugs and my manual switch setup. I have been able to reliably start my truck even when the temps are in the -25 degree (F) range, without using the block heater.