CUCV won't start. white smoke from exhaust, two bad glowplugs

[shotty]

Over the last couple days it took a few more seconds to start the truck each time, until last night when it refused to start. There is small amounts of white smoke from the exhaust and the IP solenoid is engaging, as well as the glow plug solenoid. I killed the batteries messing with it last night so while they're charging I have some time to kill.

I bought a test light that uses an LED to indicate continuity and polarity. All but two glowplugs tested good. The wait to start light functions as you'd expect once the truck has cooled down.

The fuel filter base isn't leaking. I cracked the bleeder on the filter after cranking for a bit and got some fuel out. Last night I bought some aquarium hose so I can bleed it properly today though i don't think that's the issue, unless its a filter problem.

Any ideas on quick things I can check before I start going through the troubleshooting section of the tm?

 

[cucvrus]

Fix the glow plugs if you know 2 are dead. That will make the relay cycle to quickly with 2 dead glow plugs and you will continue to have issues. I had issues with one bad glow plug. I do use magic spray on occasion if all else fails. Don't recommend doing that. But a man has to do what a man has to do. It works for me as long as you don't spray it like paint.

 

[Warthog]

Some trucks require all the glowplugs to be working.

Have you downloaded the FREE technical manuals? TM 9-2320-289-20 has a step-by-step test procedure for a no start problem.

If you have someone to help, they can hold a rag/hand over the tail pipe on the side with the bad plugs. That restricts the flow of air and helps build heat. This trick has been used for many, many years.

 

[shotty]

I have the tm's and started going through them last night before the batteries died, but I was hoping you guys might have some other suggestions for more common areas to check first. I also tried plugging the exhaust, but I don't think it helped much because its a dual exhaust.

It looks like the 12v glowplug conversion isn't complicated or expensive, so I'll do that at the same time to try and keep all the glowplugs from burning out.

 

[Warthog]

I have also seen old timers use a potato to plug the exhaust to help with starting. Just make sure you don't insert it too far and be sure the area downrange is clear.

 

[Assel]

make sure your batteries are fully charged, does you truck stay outside in the cold? without good working glowpugs its getting harder and harder ..the colder it gets...if its inside a garage try putting a heaterfan under the engine oil pan, let it warm up..if it starts up then...you know its the missing glow... you can also try blowing with a hairdryer into the Aircleaner ^^

Edit: White/blue Smoke in the first seconds/minutes after start up is unburned Diesel.

 

[shotty]

Got the glow plugs replaced and wired to 12 volts. I also replaced the small Interstate batteries that were in there with two refurbished group 31's from Interstate. I went to start it and the truck turned over once, really slowly, and that was it. Let it sit for a minute and it will turn over once more and then it's done. I checked battery voltage while cranking and its 22-23 volts. The TM says that if it's between 18-22 the starter is fine, so I'm leaning towards a bad starter. The thing is, the starter was replaced a couple years ago and the truck has only had 20 or 30 thousand miles put on it since then, so it seems unlikely it's bad.

I have the batteries back on the battery tender to charge back up fully. When I get back later I'm going to check for voltage drop on the battery cables, I have a feeling that might be it. Two of the battery terminals have the crappy auto parts store style clamp terminals. They might need to be cleaned where the copper is clamped down on the terminal. If that doesn't turn up with anything then the only thing the TM says to do is replace the starter. I'm not opposed to that as I want to do a 12 volt conversion anyways, but I really don't want to spend any more money on this truck this month.

Any ideas on what else to check?

 

[Skinny]

It sounds like you should spend some time going through starting/charging/GP systems before you make any more attempts. If you haven't done the doghead or resistor bypass, I would highly suggest them before you possibly do any damage to those systems. Without these functioning 100%, you are wasting time trying to figure out what the problem is. Weak batteries, worn out starter, and bad GP's will make you run around in circles trying to band aid things that really need to be properly fixed.

 

[shotty]

Doghead and resistor bypass are done. Glowplugs are all new and the batteries essentially are as well.

 

[Skinny]

If the engine is still cranking slow, I would be looking at voltage tests and maybe a new (I prefer to rebuild the OEM) starter. Diesels are pretty cranky (get it...) when it comes to turn over speed. You may want to look into cracking some high pressure fuel lines to see if anything is coming out.

 

[shotty]

When I say cranking slow, I mean it will turn over once, and then stop. I'm pretty sure it's the starter, it didn't want to crank at all even though the new starter relay was clicking. Crawled underneath and gave the starter the old tap-tap with a hammer, and it turned over a few more times before refusing to. The battery voltage drops to 21-22 volts as it cranks, but as soon as the starter stops the voltage rises. As per the TM, it's time to replace the starter.

*3 hours after I typed the message above*

I got the starter out, and guess what? It's a 12 volt one from auto zone.. No wonder it burned up after a lot of cranking. It was a gear reduction starter without the rear bracket. When I bought the truck, there was a bunch of crap floating around inside, including something that looked important, so I held on to it. Turns out that it's a bracket for a direct drive starter. So I ordered a starter from Napa that I can pick up tomorrow. In the meantime I'm working on a 12v conversion to put the new starter to good use with the proper voltage.

I'm just glad the truck made it as long as it did with the 12v starter and that it didn't break the bolts and fall out without the bracket. People are crazy man...

 

[Skinny]

I would put the correct one in rather than convert the whole truck to 12v...lots of good things about the 24v system. Mainly is it retains value since most 12v conversions are hacked and it tends to crank very strong with the stock 24v system. The biggest one is that the TM's still apply and help can be found here. Most bow out on 12v trucks with electrical issues.

 

[shotty]

No reason that a 12v conversion should be done poorly. The the roscommon pdf makes it pretty simple and perfectly reversible. Going to 12v doesn't invalidate a lot of the TM, you just have to know what you did and how it will affect things.

New starter installed, got the correct support bracket for it as well. Went to O'Reilly's and got some military battery terminals and then a bunch of the remade 4 gauge starter cables. Each battery has it's leads going to the terminal block on the firewall, as opposed to daisy chaining them and stressing half the cables with double the amperage. The nice thing about this is all the ends are solidly crippled to ring terminals so corrosion should be much less of an issue now. Another bonus is when I need to disconnect the batteries I undo one bolt and take the cable off, leaving the clamp in place and not stretching it out over time.

So after installing two refurbished group 31's, new terminals and cables, new AC60G glow plugs, a refurbished 12v starter, and a 12v conversion, it finally starts right up. Now I just need a voltage gauge that actually works...

Thank you to all that helped me through this. It's so nice to have my truck back.