[WV Sears]

As the title states, I'm having problems with my truck. It is a 1995 Chevy K2500 6.5 turbo diesel w/ 144,000 miles. My problem is that it is hard to start and is blowing lots of white smoke.
After reading some other forum sites I think my problem is my glow plug controller/solenoid.(any other ideas would be great).
So, that leads me to my question. What is a glow plug controller/solenoid and where is it?

 

[rscurtis]

Check all the glow plugs before you replace the controller. The controller requires 8 functioning GP's in order to work correctly. Even just one burned out will give you starting issues.

 

[WV Sears]

Ok thanks
How do I check the glow plugs?

 

[Tractor-Holic]

To test them,unplug all the wires from all 8 of them first...
Then,take a 12V test lamp,hook the lead to the positive battery terminal,then touch the probe to the glow plug's terminal--if it is good,the lamp will light...if not,its dead,and will need to be replaced..

A multimeter can be used too,to measure the resistance of a glow plug...but I've never used that method...some claim a glow plug can be "dead",yet still light a test lamp up...I haven't had that happen though...

Removing them can be very difficult--not only can the small 3/8" hex on them rust away and make getting a socket to fit well enough so as not to strip them is a pain,I've had to use vise grips or "gator" sockets to unscrew them--they only have 10mm threads too,so go easy,or them may snap off in the head!...some of the original glow plugs Gm used would swell up and make removal difficult or impossible--usually they will unscrew OK,but refuse to come out of the small hole in the head and let the tip come out--using a lot of penetrant and working them back and forth sometimes frees them up enough to get them out--in other cases,you'll need a special puller,or end up removing the fuel injector in that cylinder to retrive the broken tips if it does break off...(a rather involved job that requires intake manifold and fuel line removal!).

..some guys have started the engine up with the glow plug unscrewed and let compression blow them out,but I have been hesitant to try that method!...(I have one glow plug that unscrews,but refuses to come out on my 6.2 diesel,I just let it be,rather than cause myself a lot of greif--it has always started fine with only 7 good ones in it so far!)...

I switched my glow plugs to some AC # 60G ones,and wired my glow plugs up to a manual push button--these plugs can be left on without fear of them overheating and failing or coming apart in the engine,they usually must be energized for about 10 seconds to start easily,and most stock glow plug controllers wont stay on that long without some modification to get them hot enough...but they wont swell up and cause troubles like the stock 9G ones will...

I find often the stock wiring harness to the glow plugs and the fusible links in them are corroded badly,and dont let enough current get to the glow plugs,making you think they are "bad" when in fact they are just not getting enough voltage to heat up good enough...I've had a few glow plug relays get corroded internally that did the same thing too..

 

[Hugh-SS/16]

Have you relocated the PMD yet?

 

[rscurtis]

Testing glow plugs with a test light will confirm a bad one (no light), but continuity does not guarantee a good plug. If you have a battery charger with an ammeter, you can use that to determine that the GP you're testing is actually drawing power. Only do this for a second or two, as most modern engines use 6V GP's that are pulsed with 12V for a quick warm-up. It might be worthwhile to replace all of them- buy them from the dealer, not all GP's are created equal. I learned this the hard way with a 7.3 Ford. Spend the extra $ and do the job once- espescially since several plugs on that engine are almost impossible to see, much less change.

 

[RED-85-Z51]

Wasnt it the Cummins that doesnt use Glow Plugs? Man I hate glow plugs...

 

[matt167]

The B series Cummins were direct injected and did not rely on glow plugs for cold starts.. They will still start a little hard and blow the white smoke tho. There a FAR better engine.

White smoke on a cold startup does usually indicate it's a really cold start, but can be an engine in need of a valve adjustment.. common mod is a momentary switch for the glow plugs

 

[hodge]

The B series Cummins were direct injected and did not rely on glow plugs for cold starts.. They will still start a little hard and blow the white smoke tho. There a FAR better engine.

White smoke on a cold startup does usually indicate it's a really cold start, but can be an engine in need of a valve adjustment.. common mod is a momentary switch for the glow plugs

Yea- Cummins uses an intake heater, which works pretty good. Simple and failsafe.
It isn't uncommon for a diesel to be hard to start in cold weather- what are you calling "hard"? You may have a problem, but it would help to know how hard of a time you are having, and what is routine hard starting for a 6.5? You may just be getting used to a diesel, and not really have a problem.

 

[RED-85-Z51]

On the smaller diesels Ive had, I really had good luck with some stuff called Diesel Medic, I had a mitsubishi diesel that flat wore out a starter one winter. I did a couple DM treatments and it busted off alot faster after that.

 

[rscurtis]

A 6.5 with a properly working GP system should start clean with no missing or white smoke. I looked at one in '95 when they first came out, and it was clean from a cold start in winter. The exhaust hardly smelled at all and didn't burn your eyes.

I once had a Brush Bandit 12" chipper with a 110HP 4BT Cummins that a customer wanted to use on a winter day. It started in about 5 seconds at 6* F. with no starting aids at all. I probably should have put him off, as those cold temps. are really hard on the hydraulic system until it's warmed up.

 

[Tractor-Holic]

The loader we had at the junkyard had a 4 cyl Detroit in it--I am not sure if it used glow plugs,all I know is that thing would start within a crank or two,no matter how cold it was,and we often used our cars to jump its dead battery!..I was told it had some kind of magneto setup that fired it off,but I never really looked at the engine ,all I ever did to it was check the oil and sometimes had to jump the starter to get it to crank over--..

I wish I could screw 8 10MM spark plugs in my 6.2 and get rid of the glow plugs!!--they are an expensive pain in the butt to replace and dont seem to last long,as I use my truck only once in a while and in short trip use..I've have brand new AC 60G ones rot away so bad in 5 years they looked worse than the original 1982 ones I replaced,I had to use vise grips,smashed on metric sockets to get the darn things out!..all the connectors were litteraly fused to the glow plugs too,with rust...

 

[WV Sears]

Thanks for all of the reply's guys. The reason why it was hard to start is because the batteries were low. Yesterday i tried to start it and it would hardly turn over. So I grabbed my jumper box, hooked it up, and it started just fine. I let it sit there and run for a while, to charge the batteries. I still have no idea why it was smoking so much more than normal. Once I get license on it, Ill fill it up and add some injector cleaner. Right now I'm not to worried about it because it seems to be fine.