Truck doesn't start.

[Fordsandguns]

I would bet my right arm it's not the GP's or controller. It's the batteries, one almost new and one old just don't work, even when jumpering from another vehicle. Amen.

If the old battery is bad then you're right about that. But if it's still up to par it shouldn't cause any problems.
I vote either battery or starter.
I recently replace my starter because it wasn't spinning the engine fast enough to start. Had two new G31's and it would drag hard then speed up enough to start. I ran it until it just wouldn't do even that.
Put the new one on with the G31's and - WOW. It started so fast it scared me.

 

[amishtrucker]

Thanks all, Joe and Ford etc.: No difference when jumping the glow plugs or running jumper- WTS light on seconds first cycle, subsequent cycles 2 seconds....then, clicking on and off for 30 seconds or so. This simultaneous with the erratic jump in voltage at the GPs, the Cold Start Solenoid and High Idle Solenoid (the first two concern me as far as starting and I want to run jumpers directly today).

Starter has been brutally used since 2011 with all the cold starting problems and is a Chino brand, not original Japanese (not sure where to get a good one?)

Ordeal with that batteries is this: they are under warranty at Auto Advance and the last time they needed replacing, I went there to claim my replacement and they said it would take an hour to bench test both and they would have to get a printout to send to Corporate. After the hour, they insisted they were both good (starter only cranked twice at 10 seconds, then died, lights dim, etc., NO balls floating in my electrolyte tester). Second time, different Auto Advance, same experience. Third time, they said only one tested 'bad' and would replace it, but when he went back to get the printout, one of his guys had reset the machine and he HAD TO have the printout to replace it; he retested it and it wouldn't come up 'bad' again. Finally, I found a store who replaced them, one the first week and the other the second. I had to sit in the lot and run it down with my headlights for a couple hours before testing them. Auto Advance's warranty policy is a total SCAM! So, that is the predicament I'm in as for replacing the battery.

We can test the GPs. What should the resistance across them be? The old ones I took out tested about 0.5 to 0.7 Ohms.

 

[jonathan]

i think all auto parts stores full of bs when it comes to batteries. for instances my batteries get after 2 of cranking time so they need to replaced but the parts stores says they are in tip top shape its bs

 

[OLDBULL8]

We can test the GPs. What should the resistance across them be? The old ones I took out tested about 0.5 to 0.7 Ohms

Nothing wrong with those. The ambient temperature will determine on how long the controller stays on to heat the GP's then it will cycle ON/OFF for up to 2 minutes to keep the plugs glowing, then shut off when the engine is started.

IT'S YOUR BATTERIES THAT ARE NO GOOD! CHECK THE BATTERY VOLTAGE WHILE CRANKING AT THE BATTERIES. Bad bearings on the starter will cause the armature to scrub and pull one hell'va lot of amps, possible 800 to 1000. If the voltage fall's below 9.5 you can't crank fast enough to start, and all solenoids will go ON/OFF. I may be wrong, but this seems to be the trouble your having. Jumper cables are NOT big enough to carry the amps it takes to start if your batteries or starter are bad.

 

[amishtrucker]

thanks oldbull again, and jonathan. unrelated question: i run WVO and sometimes mix used motor oil and used tranny oil in no more than 10%. can you use 10% used SYNTHETIC motor oil mixed with WVO?

 

[towtruckdave]

thanks oldbull again, and jonathan. unrelated question: i run WVO and sometimes mix used motor oil and used tranny oil in no more than 10%. can you use 10% used SYNTHETIC motor oil mixed with WVO?

If you mix wvo and used motor oil, it will turn into death sludge. Bad idea.

 

[amishtrucker]

JD, what is a heat soak problem? what is a return side leak? have we ruled them out, or are they still possibilities?

 

[Goofyexponent]

JUst in case you all were looking for it, here is a GP wiring diagram for 1988 -1994 trucks.

You must be registered for see images attach

 

[Diesel JD]

Amishtrucker it is not the heat soak, you guys made it clear that the problem was with cold starts, that is a warm start problem. Return lines, could still be, are they leaking? If not probably not the issue. The glow plugs you took out were fine...why did you replace them? Nothing seems to work as well as the berus in these IDIs. The Bosch have mixed reviews from horrible to an acceptable though not preferred substitute.

 

[amishtrucker]

Took the GPs out because I was advised with a hard starting problem, to routinely remove the GPs and GP controller; I do not like replacing-replacing-replacing when I don't know what's wrong. I ran some new electrical tests today, here are the results. They were all WARM tests, with the block heater on all day. Tomorrow, I will run cold tests, electrically.

Oh! It always started with the heater on, though it took 3 times of long cranking, and when it started, it ran very SLOW RPMs building up gradually. Today, it wouldn't even start with the heater on all day, nor would it start with ether. Formerly, it would not 'fire' (rattle) when I tried to start, just dead/flat cranking. It is rattling like crazy like it wants to start, but no start. I suspect air, but don't know what to do to diagnose? I already ran lines direct from gas can to filter with electric pump in the middle...and from IP return line to a bottle, and kept both lines full of diesel. Same hard start. As for the filters, I replaced the canisters and re-tightened the fittings when soapy water test showed air. The only line I haven't tested is the one from the last filter to the IP intake, most of it is metal and i did the soapy water test on the connector where the rubber attaches with a clamp. But...though I changed the return lines and replaced with 1/4 fuel hose + old spring clamps, I didn't change the plastic caps, and didn't notice any o-rings (it was before I read about them). No change.

OK, the electrical tests from today:

1. chassis to - battery (GND) OK.
2. Battery voltage today is 12.29. Reading with load is 11.5v while glow plugs are supposedly on and 10.9 while cranking (with GP supposedly on).
3. voltage directly to engine coolant temperature switch (red/grey wire) is 12.29v with Key On. With hot engine (block heater) resistance between terminals with key off is 18 ohms
4. With probe on - battery and other probe to GP cap, key on, while clicking, 2v, after clicking stops, 12.29v.
5. Found what I think someone told me was a glow plug connector/harness with 2 yellow wires on the fender and pulled apart. Looks OK, one side has 4 holes the other, 3 pins. The side with the sockets/holes, holding it with the mechanical latch face up, the upper right hole has 5v going to it, the lower left has perfect continuity to the GP cap.

6. With key off, and one probe to + battery, ...
A) other probe to the black wire on GP controller, same 12.29v to BOTH ends of the resistor. (ISN'T THE RESISTOR SUPPOSED TO STEP DOWN TO 10.5V?).
B) with other probe to other large lug on controller, nothing
C) with other probe to Control wires red and red/grey, also 12.29v
D) with other probe to the WHITE wire on controller, 12.5v initially, then 11, then 0, as it cycles.

Thank you for all your help. Any more advice about air, or electrical? (or anything else?). Any thoughts about the battery and starter? I disconnected the older battery and the other one is brand new with 1000 CCA and I still have no difference in attempt to start. The problem seems to be getting worse.

Forgot to mention, went on a 6 month trip and truck was only started once in that period of time, just before we returned, someone tried to start it, but a hole appeared in a rubber fuel line and diesel tank emptied out, they introduced air and couldn't start it for a long time, ether maybe? I don't know all of what they did? Stanadyne additive/lubricant. When we returned, we primed it, started it, and had some stalling, primed again, seemed OK until about a month or two later, with the extreme cold, hard starting, until now, no starting.

 

[amishtrucker]

Thanks Goofy, for the wiring diagram. OK, I ran the tests i was told to run, cold. Here are the results: I am getting 12v to the red/grey wire of the engine coolant temperature switch (which i'm not sure if it is good or bad) and resistance between the contacts is 0.3 ohms., cold. When i turn the scale on the ohm meter up to the 200Kohm range, it reads 60.1.

With the key turned, the cold timing advance and fuel shutoff solenoid both start at 9v, then while GP and WTS light on, up to 10, then when the controller starts clicking, it oscillates between 9 and 11.5v. when it was tested hot, it oscillated wildly from 0 to 11.5v.

I was told here on the forum to disconnect the GP ground wire to the block, which I did. Then, I turned the key on and checked for voltage at the FSS, it was 11.79 v. When I disconnected and reconnected, it did make a faint click.

I did the same on the CTA solenoid and it was 11.48v and the click was even fainter, but definitely there.

The nearest GP tests out at 0.7 ohms

Any other ideas? Someone said if this checked out OK (Did it?), it is a 'fuel problem'? What exactly is that? We seem to have fuel coming through the mechanical pump OK and through the filters OK, and used to have it dripping through the injector lines when cracked (not sure now?). There is at least one leak on the top of the nut on one of the injector lines. Not sure how much of a problem that could cause?

Thanks again all!

 

[amishtrucker]

hear about the IP check valve and the inertia switch as possibility for my no-start/hard start problem. anyone know how to test them? what about the many fusible links? i see them on wiring diagrams, but don't know how to find them, or which would be likely to be causing the problem.

anyone still out there?

 

[amishtrucker]

WE FOUND THE PROBLEM!! One of Burt's friends came over. I talked with him about the solenoids and he noticed nothing was coming out of the injector when he opened it cranking. He opened the cover of the IP and manually slid the lever usually attached to the fuel shutoff solenoid. (block heater on all night, but) no glow plugs but straight to cranking and air in the injector and return lines.....STARTED RIGHT UP! For the past three weeks, has not started with ether (or even with a nuclear bomb in the intake!)

Now, the question, is the solenoid faulty, or is that lever inside the bowl of the IP supposed to spring back on its own? I bench tested the solenoid (without load) and it appears to function quite well and strong. A friend looked at it and thought that the SPRING on the solenoid actually causes the lever to spring back to the open position so fuel can enter the IP, not anything having to do with the lever. Anyone know if this is true?

If that is the case, where can i get replacement spring? And, the washers that seal the unit , which deteriorated when we removed the cover?

 

[s.blake57]

do u have 12volt power to top of injection pump the double red wire that attaches to "top of injection pump", check there! and also u can have a bad fuel shut solonoid in top of injection pump i worked in a fleet of 7.3 idi engines we had problems like that all the time ****** connection at pump or weak/bad fuel shut off solonoid in top of injection pump

 

[Diesel JD]

I'd just replace the entire governor cover. I'm pretty sure one from a 6.9/7.3 or 5.7 or 6.2 would work. Double check before you go doing it though. I have one that functioned when removed if you want it and I can find it. It's yours for the cost of shipping. Please be careful with the governor cover off. If anything (dirt etc) drops in there it could destroy the pump, and also if for some reason that lever arm is jamming or you don't have electrical control of the pump with the key you could have a runaway situation. I'd always keep a clean piece of plywood, clipboard or maybe a hard bound big book close by to clap over that air intake if it starts to runaway uncontrollably. I'll go look for my parts bag if you're interested.