Smokes White and no start

Can't be Glow plugs, can't be Glow Plug Relay, checked fuses all new and good. Fuel filter and system is good to go...
I replaced the glow plugs one year ago with correct 070 Wellman GP which it had in it when I bought from military.
I had trouble starting it last week so I replaced again,
worked great for a week. Same thing, white smoke no start.
I am not replacing the gp's again. I've had this for 3 years and had two sets installed now!
I replaced the GP relay from anohter cucv I have that works right.
So it is not the GP relay.
I checked all my fuses, replaced them all with new ones when I got it from the military. I am totally stumped, reading -20 now under trouble shoot no start. By the way the fuel system is good. HELP

Glow plugs not heating up. Your missing something. Check all the wires, the big relay on the fire wall.. ect.. time to get out the volt meter and start probing.

and why would you replace all the fuses with new ones if there not burnt out? Just asking

Sounds like you ruled everything out. So you may need to start over. I would disable the glow plug system and see if it starts with starting fluid- if so then the problem is most likely the glow plug system. This test would rule out the fuel system if it starts and then continues to run. Starting fluid will make a marginal engine at least fire even with some mechanical, low compression or slow starting speed problems.

hmmmmmmm, white smoke and it won't start. Sounds like a new pope has been elected and you've got engine problems. Just kidding. Sorry I can't help with the mechanical problems, but the white smoke/pope line was irresistible. Any chance you're getting coolant in the cylinders? That might be the source of the smoke and would inhibit motor starting.

Thanks Westech

Westech said:

Glow plugs not heating up. Your missing something. Check all the wires, the big relay on the fire wall.. ect.. time to get out the volt meter and start probing.

and why would you replace all the fuses with new ones if there not burnt out? Just asking

Click to expand...

Checked all wires, Checked GP Relay You must mean the Resistor Hmmmm
I replaced all the fuses when I got it because well heck they looked 25 years old so for 3.00 I figured why not, I replaced all the bulbs in the dash and exterior lighting as well for less than 50.00, again I figured why not - cheap enough...

It does run when I give it a shot of starting fluid and runs and charges perfectly. I've had to do that now twice, once when I first got it - so Mangus580 helped me change them,
once last week when I figured they'd failed,
and the other day to get it back home after sitting all night.
Question is: Why did the brand new plugs fail after 1 week of use?
None of the plugs I have ever changed have been swollen like many speak of.
Thanks for the idea Ken_86gt

It's diesel smoke

OldDominionIron said:

hmmmmmmm, white smoke and it won't start. Sounds like a new pope has been elected and you've got engine problems. Just kidding. Sorry I can't help with the mechanical problems, but the white smoke/pope line was irresistible. Any chance you're getting coolant in the cylinders? That might be the source of the smoke and would inhibit motor starting.

Click to expand...

Coolant level is correct,
oil level is correct
and it's oil on the dipstick
thanks for thought though OldDominionIron.

well there ya go... you now know its a GP problem. just check it again.... when i get stumped on a job i will walk away.. eat some lunch and start from the top again. Sometimes this takes awhile but i do it. And I mean start from the top.. don't skip anything.. the thing you say is good and you pass it up it what is causing the problem every time.

Souinds like glow plugs to me. If even 3 or 4 are bad, it won't start in the cold. Replace the plugs and then figure out if the firewall resistors are bad or what else is causing them to fail to easily. The resistors should each Ohm out at .28 Ohms +/- 5%

OK, this definitely seem to be glow plug related. With the engine cold put a voltmeter on the wire that goes to the glow plugs and measure the voltage when the key is first turned to run - should be about 12V. Test each glow plugs resistance, with the wire removed, and verify something like .5-1.5 ohms on each. If it passes these tests let us know and we can go from there.

Glow plugs can fail on the very first use- especially if they have more that 12V on them. When you measure the voltage on them when the key is first turned I would be concerned if there is more than 14-15 volts. Glow plugs are like light bulbs, they are rated for 12V, if too much voltage they will burn out. This could happen when 1 or more are burned out, loose connection on the plugs not making good connection, or the big resister on the firewall is shorted.

Ken_86gt said:

Glow plugs can fail on the very first use- especially if they have more that 12V on them. When you measure the voltage on them when the key is first turned I would be concerned if there is more than 14-15 volts. Glow plugs are like light bulbs, they are rated for 12V, if too much voltage they will burn out. This could happen when 1 or more are burned out, loose connection on the plugs not making good connection, or the big resister on the firewall is shorted.

Click to expand...

Good to know and thanks - I did notice the connectors seem to slide on easy and one connector is pretty oily,
from a past leak I would guess from the valve cover.
I bet it's the resistor block behind the air cleaner housing!
I'll have to check the ohm's at GP's and maybe I'll have to move the red wire to the diamond shape 12v block,
I know it's a last resort due to the excessive drain over time on front battery.
I will also clean up all the GP connectors by first removing the old greasy plastic off from spade connectors Then just use the metal spade connectors only, tighten metal spade connector and reinstall on new gp's. Stinks to think I killed a brand new set of GP's after 5 starts in one week. If it is the Resister and I have to move red wire isn't it recommended to change gp connectors size and switch to ac60g's?

Don't get ahead of yourself and replace everything just yet. You should still do the tests, there is still the possibility that it is just the glow plug relay. I had an intermittent one on mine that was hard to find- sometimes it had 12V going to the plug and it always made the audible click making it seem like it was working just fine.

Also, moving the glow plugs to be fed by only 1 battery is not excessive at all, in fact it is exactly the same load. This is because half of the load is that resistor when across both batteries. The reason for the resistor is so that it would be compatible with the slave jumper (24V). But do your research if you move that wire.

I don't have a multi meter, my father will read the posts you guys have made and check it all out. I took the glow plug relay off from a good running cucv and put on mine, no difference. I tried my gp relay on the good running cucv that was cold and it fired up normal so that ruled out my old gp relay. I'm leaving the one I stole from good running cucv on mine - it was just replaced by military prior to sale and is new

I had a problem with a set of new glow plugs. My connection at each plug was not good, I tried bending them so they would fit tighter without success so I replaced them all so they are tight, and it ended my problem. One bad connection is all it can take to start burning them all out. My first set lasted about a week too and then the truck wouldn't start.

Ended up being the Resistors, in the Resistor Bank, mounted on the firewall behind the Air Cleaner. Dad tested when I turned the key on and 24 volts was comming out going to Glow Plug Relay those frying 2 sets of glow plugs. I moved the wire from the resistors up to the diamond shaped 12volt block right nest to the GPR. Now lets see if I can get more than a week or 10 starts out of these glow plugs. Hopefully this is my second to last post on this issue, if I'm right in my discovery than I will post one more post reply a month out after a few dozen starts with GP's.
I haven't installed any GP's in her yet to see if someone thinks my Diagnosis is wrong. Any takers? Mike - (Mangus580) Doghead, Recovry4x4

PM me your number, I'll give you a call and try to help you. If you want.

PM sent

I have what sounds like the same problem. I have noticed when it does not start the wait light stays on for a long time. Then there is a click and the light goes off but it will not start. I turn the key off and back on until the light goes off without a click and it will start. What is that? I am bout to change the card out with one from another truck to see if that is it. I see the relay should be changed but I look at the picks and have no clue if I have the old or new one.

Could be the gp control card? Pull out easy like and check for leaks or most common a broken burn spot. That's usually the ground (light blue wire on gp relay. You can try to fix your card or put a momentary switch in the dash, ground to the dash to complete the ground to activate gp's. My issue was the Resistor block behind the air cleaner. It allowed 24v's through it thus through the gp relay and down to gp's killing them after a week, maybe 10 starts! I removed the resistors and swong the red power wire to the side and monted on diamond shape 12v block. If my Gp's fail in a week or two I'll know it wasn't the resistors that failed and it is something else. Your gp's may just be bad! Which ones? How long they been in there?

Any updates? Did moving the wire work?

I'm having the same problem, truck always started even in the dead of winter then last week nothing.
I turned on the key and cycled the glow plugs, but I never heard the click when the GP light went out?
Then it cranked and no start, with white smoke out the exhaust.
I plan on looking at it this weekend just wanted to see the outcome of this post.

Chad.