I have noticed my wait to start light is not staying on as long as it did (only 3-6 seconds now, was about 10 seconds). The weather is getting cooler up here and I would think it would be staying on longer. I can hear the clicking of the cycling, but the truck seems alot harder starting then it was when it was warmer and the wait to start light was staying on longer when it was 50 degrees at night. Is it the glow plugs or something else? If I plug the truck in at night (only getting down to the upper 30's right now), she pops right off in the morning. I am also noticing a sound from the right side of the motor when cold, almost like valve chatter, making me think the plugs might not be warming all the cylinders on that side.

Any ideas or ways to check this out before we really get cold?

 

Sounds like my problem too, I am thinking its the contacts inside the relay that have been corroded and are now not making a good connection. Check out my post for more info. I am waiting on a little more info and then tonight hope to test that the GPs are getting power, just not sure how to set-up the test light.

 

First test:
To test the glow plugs.
Using an automotive test light with the ground clip hooked to the positive battery terminal.
Remove the connector from a glow plug, touch the test light tip to the glow plug terminal.
Light lights, the plug is probably good.
Light does not light, plug is bad.

Replace your glow plugs only with Motorcraft/Beru plugs, the others are bad about swelling and deforming which results in broken off tips. That is bad news.

To test the relay for power passing through:
Using the automotive test light with the ground clip on the negative battery terminal.
Have someone turn the key to ON while you are touching the terminal in the glow plug wiring harness terminal.
The light should light.

If both of you would go to the blue bar and click on USER CP, then edit signature and enter your known truck info like year, engine, transmission, drive type ( 2 wh Drive or 4x4) and gear ratio if known it would make it easier to answer your questions.

Prime example, the glow plug system was completely changed from the 86 to 87 model year. What year are either of your trucks?

 

Thanks Dave, checked the plugs last night, three were bad, changed them out and it is back in business, light is stayed on a full 14 seconds this morning and she fired right up.

Thanks guys.

PW

 

Thanks for the heads up Dave, I had missed that signature button.

pwhnts, good to hear your back in business again. I went out and tried to start my truck last night, sat down and .... wow the light came on for about 8 seconds, I thought it solved itself so I turned it over and she came to life for about 1 second Tried to power the GPs again but they would only stay on for 1 second if that.

I am fairly certain now its my contact points or something because the problem is sporatic (sp?) ... Going to try your test tonight Dave to see if power is infact making it through.

-Joe

 

GiS,
I just saw you have an 86 like mine so here is a problem I found.
There is a connector where the truck wiring harness plugs into the engine harness.
Look at the connector very carefully, on one end of the connector there are two large orange wires with a white stripe.
Look for any sign of the connector having been overheated.
Mine had a melted kinda rounded look to it several years ago.
Had all kinds of glow plug problems.
When I tried to disconnect the connector, it was melted together.
So I cut the large orange wires real close to the connector and then spliced all 4 of them together with a copper split bolt and wrapped them with some good electrical tape so they could not short out.
Glow plug problem went away till the controller died a year or so later.
The large orange wires are power from the solenoid to the glow plugs, they hook together on both ends so you can just use one split bolt to connect them.
The rest of the wires were OK in the connector so I just left them there.
Those orange wires carry a lot of juice so I wanted something that made a better connection than a crimp on splice does.