Cranks but won't start

[jcbrooks75]

Greetings,

My CUCV cranks but won't start. I've started my way down the diagnostics in the manual. Here is what I can say so far:

1) All the glow plugs appear to be fine. I check the resistance on each one and ensured the proper voltage.
2) I've disconnected the fuel input at the fuel filter and there is plenty of fuel
3) I've disconnected the fuel output at the fuel filter and there is plenty of fuel (through the filter)
4) The fuel quality seems good although I'm not sure if I would notice otherwise (smells like diesel to me)

Is it possible that the fuel filter itself is still a problem. I've read that the fuel filter is able to separate out water from the fuel. Does the water stay in the filter. The fuel filter installed is a cylindrical type and is not the filter depicted in the manual. Feel free to state the obvious as I am hoping I missed something easy.

Thanks
Jon

 

[cpf240]

Is the fuel shutoff solenoid on the IP getting voltage? The pink wire? Can you hear the solenoid click when the key is in the run position and the pink wire is connected / disconnected? If there is a problem there, then no start.

You could loosen a fitting at one of the injectors to see if they are getting fuel. While you tested the glow plugs, I assume it was via a resistance check? Might check the voltage on the glow plug side of the glow plug solenoid when they are supposed to be on. The contacts inside the glow plug solenoid can get carboned up, and not allow proper voltage/current to the glow plugs. You could try jumpering the two large posts on the glow plug solenoid for a few seconds if you suspect the solenoid, and then see if it will start.

 

[GPrez]

You definitely have a fuel filter that is not original. The aftermarket ones usually have a petcock on the bottom to drain water. You can always change the filter to be safe, but loosen the lines at the injectors and see if you are getting fuel to them. You may need to bleed the lines. Air in the lines will keep it from running.

As the previous poster suggested check for voltage at the glow plugs when you first turn the key and make sure the voltage is getting to the plugs.

 

[jcbrooks75]

"Air in the lines" may be a possibility. I assume the low pressure fuel system should remain pressurized even when the vehicle is not running. Is this correct? When I opened up the lines to the fuel filter I was expecting to see fuel but there was none. Is it possible that the fuel system is depressurizing due to a leak, bad seal?

1) I recall hearing the solenoid click but will verify with a voltage test
2) I did check voltage at one of the glow plug connectors and looks correct but will recheck
3) The fuel filter does appear to have a drain. I will drain and/or replace (see picture attached). Will this fuel filter spin off?
4) I'll verify fuel at the injectors

 

[CUCVLOVER]

Yes it should stay pressurized. The filter does spin off, and have water separator that's the knob on the bottom, just remove the filter and take to your local Napa, motor parts, autozone, ect..

Also who painted the engine compartment of your truck?

To check fuel at the injectors just loosen the nut that holds the line to the injector, I believe it is a 3/4 wrench, just watch the return lines.

Hope this helps somehow.

 

[jcbrooks75]

I removed the air from the system per the manual and was able to start the truck up last night. I let it run for 30 minutes. This morning it started right up. The top plug on the fuel filter (which I used to bleed the air out) is seeping a bit of fuel. What is an appropriate thread sealer to use? Can I use the same sealer on the input and output lines to the fuel filter? Also, besides the fuel filter what are other potential sources of air being introduced into the fuel line?

As for the paint job the likely culprit was someone with a beer in one hand and a paint can in the other (AKA one of the previous owners). The worst part about the paint job was he sprayed the heater controls, the transfer case shifter and the fuse box!

Thanks again for all the help