Newb with more Glow Plug Relay Questions

[phcoffeedrinker]

I just recently purchased my first CUCV and I am running into my first problem. Which from the posts that I have looked through it almost sounds like a recurring thing with this part.
The truck was running fine, now it won't start. I have been reading the posts that have been on here but nothing seems to be exactly it. I turn the key and wait for the wait light to expire and if the key is left in the on position without cranking the engine the glow plug relay makes a nasty noise, not the normal clicks that I should hear. I would assume that this means that this GPR is bad but I wanted to get some opinions. Or if this means that the glow plugs are bad? How do I go about testing the glow plugs to see if they are still good? My voltmeter is also past left, still need to check my batteries, maybe there just isn't enough juice? Sorry to ask the question about the glow plug relay again I have noticed that it is a common topic. Any help would be appreciated. Thanks

 

[badgmc56]

RE: Newb with more GPR questions sorry

You MUST have GOOD batterys and connections before you check anything else. That includes GROUND WIRES too.

 

[phcoffeedrinker]

RE: Newb with more GPR questions sorry

I am definitely getting the batteries checked tomorrow, thanks.

 

[JohnFire]

RE: Newb with more GPR questions sorry

most diesels that I have driven when the battery voltage is low you get rapid clicks when trying to start instead of your starter cranking. The relay is common problem cause they aren't real good relays. To replace the relay with a stock model they are only about $10 at a parts store. I think the better ones are probably about $20. The other guys on here can tell you which one. I know it is in some of the other posts. I just replaced mine with a stock one, knowing that in the future I might have to replace it. The glow plugs won't cause any noises to happen when they are bad.

 

[mangus580]

RE: Newb with more GPR questions sorry

Define 'nasty' noise. Is it a 'chatter'? Like the relay cant stay engaged?

 

[acetomatoco]

RE: Newb with more GPR questions sorry

Go get those two new group 31s and get em in there... Probably will help solve your problem... If your volt meter is not at the top of the yellow with the glow plugs heating... you will have problems... your wait light is on a timer and is not indicative of how well your plugs are working...my glow plug relay does not click off until about 10 seconds after the light goes off...you can test your glow plugs individually after you take em out with a ohm meter to the specs by manufacturer found in your manuals...

 

[mangus580]

RE: Newb with more GPR questions sorry

Ohh... I missed the battery problem... low voltage will cause a relay to chatter

 

[Michael]

RE: Newb with more GPR questions sorry

One of my GP relay makes a rasping sound when it disengages. Kind of like a starter that doesn't have enough power to engage. My truck is fully charged and starting just fine. I will probably change it out, but since it is still doing its job it is not on the priority list of things to do. Do your batteries turn the truck over at a reasonable speed? If it is turning over but not starting and you GP relay is making funny noises, I would check it with a digital volt meter to see if power is going to the plugs.

 

[CCATLETT1984]

RE: Newb with more GPR questions sorry

to further test the relay, without the need for a second person. you can make a jumper to go from the small terminal on the GP relay (the one with the light blue wire) to a good ground. this will activate the relay. that way you can take voltage measurements more easily.

 

[phcoffeedrinker]

RE: Newb with more GPR questions sorry

Okay here we go. Got the batteries tested today, one was bad, replaced the battery and it still will not start. The GP relay doesn't make that noise anymore now that the other good battery is in there. I am getting 24v still going into the GP relay but am seeing nothing coming out of it with the key on. Wish that I had a garage to work in with some light that would make things easier since it is night now. Thanks for the help so far.

 

[CCATLETT1984]

RE: Newb with more GPR questions sorry

if your getting nothing out, the relay is bad.

 

[crusty]

RE: Newb with more GPR questions sorry

You might also want to check the fuses under the inst panel. The amps labeled are correct but some of the other labeling isn't. (IGN for instance is used for the passenger side alternater.

 

[phcoffeedrinker]

RE: Newb with more GPR questions sorry

I would like to thank all of the responses to my questions. I got it running again. Ended up replacing a battery, replacing the GP relay, and I also put in new fuses. Once again thanks for all the help.

 

[Hoot_223]

RE: Newb with more GPR questions sorry

with these systems it is adviseable to replace both batterys

 

[mangus580]

Re: RE: Newb with more GPR questions sorry

with these systems it is adviseable to replace both batterys

This is true ANYTIME you have dual batteries....

 

[phcoffeedrinker]

RE: Re: RE: Newb with more GPR questions sorry

Here we go again. Not all that long ago I had posted that my truck ran again. Well, today is a new day and upon trying to start it today I come to find out that it doesn't run once again. I am getting the correct voltage readings coming out of the GP relay, I replaced the starter relay, fuses are still good, batteries are good, voltage to the starter is correct, wait light seems to be working correctly. The only thing left for me to think of is the GPs or is there something simple I am completely missing? This is my first diesel so I am still learning the ropes.

 

[jwaller]

RE: Re: RE: Newb with more GPR questions sorry

have you ohm'd out the glow plugs to see if they are actually getting warm? are you cycling the plugs 3 times before you try the start?

 

[JohnFire]

RE: Re: RE: Newb with more GPR questions sorry

Have you prayed to the CUCV Gods! They are a very finicky. A sacrifice might be in order. Don't worry most of us have been in your shoes!

 

[phcoffeedrinker]

RE: Re: RE: Newb with more GPR questions sorry

What exactly do you mean by cycle the glow plugs a few times. I turn the key let warm for about 15-20 seconds. I am not sure how to check the ohms on the glow plugs. Will I have to pull the plugs out in order to do this? I think I may just replace the plugs anyways, probably couldn't hurt anything. I will update later on today.

 

[mangus580]

RE: Re: RE: Newb with more GPR questions sorry

phcoffeedrinker.... you might want to search the forum a little, and do some research. I know I personally have detailed testing the Glow Plug system numerous times for people, and I am sure others have as well. Please, go take a look. Everything you need to know is most likely already out there.