Need some help/advice, strange problem,.

[zukgod]

Hello all I have lurked for some time here and have learned a ton thank you. But now I have a question that I have searched and can not find the answer to. I have a 1990 7.3idi in a 4x4 truck. The started went out, and not having a diesel before other than the tractor, I tapped on the little regulator on the passenger fender well and even started it that way a couple times. Now when I installed the stater like an idiot I did not disconect the batteries, and had one and only one small arc. Now the truck is almost imposible to start cold. Once warm she fires right off.
I have noticed that before installing the starter when everything worked fine,when I would start it there would be the glow plug click for a bit while the truck warmed up, now I don't have that. I checked the glow plugs with a light and they all seemed to work fine. When I turn the key it still says wait to start like they are working, but something is wrong. Any help would be much appreciated. This site has helped me solve a ton of other problems already.

 

[punkmechanic]

When you say "checked the glow plugs with a light" do you mean power to the plugs or using the plugs as a ground for the test light?

I doubt that an arc would kill the plugs, but it could "theoretically" damage the controller. Even that I doubt.

Did you replace the starter with a same type starter? Was it a new starter? Are you sure all the connections to the starter are tight and that the starter to block (ground) is good?

Please go further into detail as to the issue you had, what you did to fix it, and how you came to the conclusion to replace what you did.

Punk

Thanks for coming out of the shadows and welcome to OB!

 

[zukgod]

Thanks for the reply. When I tested the glow plugs I used a light as a ground. I was very careful to replace all wires I saw when replacing the starter, but did not see a ground down there. I will check that today. The starter worked a couple times after it started acting up then just would not work at all, so I replaced it with the same kind that was in it but a different brand, it's a high torq. I have not had any other problems other than my brake vacum was lost the same day as the starter but I figure that's just a concidence because I can not find anything to connect the two. Once I sparked the starter I took all the cables off the batteries.

Any help where to look would be great.

 

[punkmechanic]

The vacuum is a conidence. The vacuum pump is ran off the belt and has no electrical components.

The starter has no ground wire, its grounded by mounting it to the engine.

Im starting to wonder if the arc might have burnt a fusible link to the fast idle and / or advance solenoid.

Your gonna have to do the base electrical diag and see what is what.

Use your test light and check for power at the fast idle and advance solenoid. These are located on the Injection pump. The fast idle is a small cylinder on the top of the pump between the injection pump and the upper radiator hose outlet. The advance solenoid is the connector on the top of the pump housing towards the rear. If one of those is acting up it will give you cold start issues.

The next thing to check is your glow plugs. Pull one out and see what kind it is. Using an ohm meter test the resistance of the glow plug. Put one lead on the tip of the glow plug where the electrical connector goes and put the other lead on the block. It should be 0.4-0.8 ohms. The test light trick works sometimes. I just had a truck come in with a set of champion plugs that would light the test light but had 2-3 ohms resistance and wouldnt heat up in the time the controller had them on.

Check this and let me know what you find.

punk

 

[zukgod]

Thanks a bunch I will have to wait until it stops storming outside to check, But I will keep you in the loop. I really appreciate you taking the time to help. It may be a partial glow plug issue but why would it stop clicking through the plugs after start up?
On a side note how do you like that mercedes diesel? I am thinking of picking one up to use as a run around car.

Josh

 

[Willie Two]

On my truck the starter solinoid is on the passenger side fender, that is where the power to the glow plugs and the GP controller start ( 2 fusable links ). But maybe on your year of truck these fusible links are different.

 

[zukgod]

Okay I tested the GP's,fast idle and advance solenoid, they all have power going to them when the key is on. But I used to hear a click click click once the truck had started or if I did not start it It would do it after the GP light turned off, I do not have that click any longer, any idea what that click is and what controls it, I know what it is it's the GP's clicking on and off to keep everything going, but what controls that? Also any other idea's what might be wrong? Thanks for your time.

Josh

 

[Willie Two]

I believe the GP controller is actually in two parts, the top part is the electric soliniod or relay ( like a starter relay ) and under that relay is a timing module that is solid state encased in plastic. The module provides power to the relay coil and fires up the glow plugs. That is how it is on mine I think.

 

[zukgod]

Willie

Do yo have any idea how to test that? Or both of those parts? Thanks for your help.

Josh

 

[Willie Two]

I have service info on my truck, 91 / 7.3 I don't know about earlier years. What are you driving ? Send me a PM with an E mail address and I can send you what I have.