Glow Plugs/Replace, or not?

[DickWells]

Hi Guys: Just got back to VT from the sunny South.
Had to come back a little early to attend a new Grandson's adoption. Couldn't miss that!
Turned 160,000 on the old Sub. just north of Albany, NY the other day. Been wondering. With that kind of mileage, should I just put in a new set of glow plugs as a matter of course? The thing still starts instantly (1-3 revolutions), cold or hot, when I glow it. I always glow it. Takes from 9-14 seconds, depending on the outside temp. and how long it's been cooling down. Makes me ugly when the guys don't glow it when I get it serviced on the road. The young lady out in southern California a year ago, was the only one who just went ahead and glowed it like she just did it automatically. Just shows, you never know!
Thing is, I don't know what number of plug is in there. I don't recall ever seeing glow plugs mentioned any time I've pulled a computer history at the Chevy shop. What are the chances that I have any swelling, or other nasty degredation of the plugs, since they may be 9+ years old now?
Just need some expert advice.
Thanks.
Dick

[DmaxMaverick]

They are easy enough to test. Use a test light, clip on bat + and touch the spade on each plug (disconnected, of course). Light = good. No light = bad.

As far as worring about swelling, too late for that. With that many miles on them, either they are already swelled, or aren't going to. No point in replacing a good plug under your circumstance.

I'm really surprised that they still work, as you glow with every start. In my educated opinion, glowing a hot engine is not necessary. It will only shorten the life of the plug, but you don't seem to have to worry about that. My '85 6.2L has manual glow control, and I don't glow it unless it is needed. In the summertime, I don't even glow a cold engine (sitting overnight) if the temps have been above 95

[DickWells]

Thanks DMax: I like your thinking.
The only reason that I glow for every start is that my 6.5 starts almost as fast as a Cummins if I glow it. But, if I don't glow it, even in warm weather, it takes maybe 8-10 revolutions before it starts. My rational is that given the reputation of the stock starters, that instant starts are a lot less stress on the starter. I intend to replace the starter with a Mean Green, or whatever the heck it's called, as soon as mine shows signs of quiting. (Or quits!) I've even concidered doing it anyway, just to avoid having to do it on the road, but I guess I'll take your advise and not fix it until I have to. Right now, I'd rather replace glow plugs than starters.
Thanks again.
Dick

[patrick m.]

Dick, you prolly have AC 9G plugs, i did. I replaced mine a few months ago, got the 60G.
All of my old ones were fine, but like you i was worried. (185K) miles.
better to do it sooner than sorry ;)

[ 04-20-2004, 03:10 PM: Message edited by: Patrick m. ]

[DickWells]

Well, gee. Thanks guys! Now I have two pieces of info, both great suggestions, from two obviousely experienced people, and I'm still in a dilemma. So, now you know what I'm going to do? I'm going to sit back and see if anyone else hits on this thread, and go by the majority. Really, I'm not trying to be SA. Just trying to inject a little humor. I really do appreciate anyone taking the time to respond to my questions. Either way, I don't think I'm at any great risk, no matter what I do.
Thanks guys. Bless you both.
Dick

[tom.mcinerney]

Mine came with 9s, and some other members have found old style. Mine were fine (don't know if original), but replaced while at it.

[Wheat Whacker]

Well when I had my injectors replaced at around 130,000 I had them also replace the gp's even though it was still starting good. I got a set of JK's quick heats. Wow what a difference. It started even better and I thought it was good before. I guess I figured it was cheap maintence as gp's are not really that expensive but then again that's just me.

[rhill2901]

I wouldn't replace glow plugs that tested good just because of the mileage. Its amazing that you have been able to get them to last that long though....

[moose1]

I have about 180,000 km on my original injectors and glow plugs. The truck always puffed a little white smoke even when new, but in the last 6 months it has steadily gotten worse, still white smoke but it is harder to start when cold. When warm or running it is fine. I hope it is as simple as replacing the glow plugs. Any thoughts. Thanks.

95 K2500 6.5 td ext cab K&N

[ttpost]

I JUST REPLACED MY GLOW PLUGS,AS WELL AS ALOT OF OTHER PARTS,MINE HAD 9GS(PUT IT 60GS) AND I DONT THINK THEY HAVE EVER BEEN REPLACED, BOUGHT THE TRUCK USED.IT ALWAYS STARTED HARD,SINCE I HAVE OWNED IT.MY DECIDING FACTOR WAS AFTER READING ABOUT THE HORROR STORIES OF SWELLING AND BREAKING GLOW PLUGS I FIGURED IT WAS CHEAP MAINTENANCE.I AM GLAD I DID IT, MY # 5 GLOW PLUG HAD STARTED TO SWELL AND I BARELY GOT IT OUT.IT UNSCREWED THEN WOULDNT COME OUT, SO I PUT PRESSURE ON IT WITH A SMALL PAIR OF NEEDLE NOSE PLIERS AND KEPT ON ROTATING IT,(SWEATING THE WHOLE TIME), BUT IT FINALLY WORKED OUT IN ONE PIECE.I DONT KNOW WHAT WOULD HAVE HAPPENED IF I LET IT GO FURTHER.I GOT MY GLOW PLUGS AT AUTOZONE OFF THE WEB.THEY WERE AC,S AND COST ME 7.99 EACH.I FEEL THAT IT WAS WELL WORTH EVERY PENNY.I FOUND IT FAIRLY SIMPLE TO DO THE JOB.I REMOVED THE DIRT COVER ON THE FENDER WELL ON THE RIGHT SIDE, SPRAYED EACH GLOW PLUG WITH PENETRATING FLUID, AND REMOVED AND REPLACED THEM.NO 8 IS A BUMMER THOUGH HAD TO DO IT BLIND.GOOD LUCK