CUCV and Glow Plug issues

[trooper632]

OK, I have looked and read related posts trying to find my issue, This is the issue.

1. Glow plugs don't heat up, though maybe gp relay might be bad, hear the clunk of it when key is turned but it cycles on and off repeatedly.
2. I put a manual momentary switch on thinking maybe that would work, seemed to, push button hear the clunk and goes off when button released.
3. Still not heat at glow plugs, but it seems to be getting power to them, checked with light tester, when button pressed tester lights up very bright (24 volts getting to it) while toughing glow plug spade. (Each one)
4. Changed out glow plugs, Nothing wont start, use just a little starting fluid (I know DONT) but just a little and it starts.

Could the glow plug relay still be bad even though it seems to be getting power to the plugs, The plugs are not new but take outs from another vehicle, I am not for sure if they all work, but I figured they all could not be bad, they did start the other vehicle when last started.

What next???

 

[porkysplace]

Test the glow plugs one at a time , follow the the directions in the TM on testing them.

 

[Warthog]

Check the ohm reading on each plug. They should be about 1.5 ohm.

 

[Recovry4x4]

And yes, you could have a faulty carboned up relay. Mine would show voltage but not enough current to fire plug.

 

[MarcusOReallyus]

3. Still not heat at glow plugs, but it seems to be getting power to them, checked with light tester, when button pressed tester lights up very bright (24 volts getting to it) while toughing glow plug spade. (Each one)

You should NOT be seeing 24 volts at the GP. You should be seeing ~12v.


Is that measured with a meter? Or only the test light?


If you really have 24v at the GP, the GPs are all bad. Not likely, since they started another vehicle, but you really need to TEST WITH A METER.

Test lights have their palce, but you need actual measurements to properly diagnose most problems.

You can buy one for ten bucks at most auto parts stores. It won't be a great meter, but it will do what you need to do.


Once you have that, measure the GPs per the procedure in the TM, and measure the voltage at each GP while the GP relay is engaged. Also measure the voltage at the GP relay terminals both while the relay is OFF and while it's engaged (ON).

You might need a helper, unless you have some extra hands.

 

[antennaclimber]

Your GP relay may be a bit on the tired side. The contacts need to be clean and not burnt or coated with a carbon build up.
Karl

 

[trooper632]

Thanks, Didn't have time to check it out today, will try tomorrow and get back with an answer.