It runs, then it doesn't.

[Shaun387]

Okay, I bought a 93 M998 about a month ago. It didn't have batteries, had a terrible oil leak, but ran according to the previous owner.

I got it home, put new batteries in it, it'd crank over, but not start. Hit it with a shot of ether and it ran......put out white smoke for about 20 seconds, but cleared up. Found the oil leak and fixed it. It'd restart easily when it was hot. When cold, it took ether, would start with white smoke for 20 seconds, clear and run great. Come to find out, the glow plug portion of the Nartron EESS was fried. All the glow plugs still ohm'd out good. Decided to run an independent relay and push button for the glow plugs. FYI, I'm in south east Texas where it's usually pretty warm this time of year.

While waiting for the relay to come in, the stock on/run/start switch got stuck in the run position for a few days and killed the rest of the EESS. Opened it up and there was water in the EESS....independently tested the solenoid inside the box and it was no longer good. Decided to get rid of the circuit board since I was already doing the glow plug push button. Ordered another "run" solenoid. While waiting for parts again, I decided I should change the fuel filter and water separator. Electrical parts came in, wired it up, and primed the new filter as stated in the TM.

It took it forever to start, but did, sounded okay too. It would idle for about 3-5 minutes, bobble and die. It would start right back up. Figured it was getting any air in the line out. Did this about 3 or 4 times, and the last time it died, I just left it down and would continue the next day.

The next day comes........doesn't start at all, not even with a shot of ether. I was getting a strong stream of fuel coming out of the filter to the IP, but it didn't seem the IP was pumping out. Both the cut off solenoid and cold advance solenoid were "clicking" fine. Took off the injection line at the easy to get to passenger cylinder, cranked it, but no fuel was coming out....zero. Ended up cracking each injection line at each cylinder (just the easy to get to one completely separated from the injector). Took a ton of cranking, but was finally getting "spurts" of fuel out the one I disconnected.

Does that sound right? Just spurts of fuel? Anyway, tightened them all back up, but still no start. Took a break for an hour or so. Came back, and it cranked and ran. I have no idea why it decided to start now. It would still occasionally die during idling . I bumped the throttle lock up a bit, and let it go like that for about 20 minutes. Drove around the neighborhood for about another 20 minutes, thought it was all good, went back home. Killed it, let it sit for about 30 minutes, loaded up the dogs for a final neighborhood ride, rode for 5 minutes, came to a stop sign and it just died again. Couldn't get it to restart for anything, not even with ether. I'm stumped.

Couple of things I've done as well. Removed both check valves near the fuel tank for supply and return. While the return was loose under the vehicle, I connected a hose and ran to a bucket....cranked it and was getting fuel to the bucket. I also installed a clear hose on the return coming off the IP to visually see flow.

Where should I start now?? It almost acts like the cut off solenoid shuts it down, even though it's still getting 24v and engaged. I did take the cover off the IP and it seems the thing that slides for the metering valve moves freely.

EDITED to add I also installed the secondary grounding harness as recommended by most members here....

 

[Mogman]

Welcome to the forum.
NEVER EVER use ether on a high compression diesel engine.

 

[Elijah95]

I’ll start by saying there’s a 95% change you’re sucking air. I come from 7.3 and 6.9 idi trucks and they are notorious for failing fuel return lines allowing air in after shutoff, will run fine and never drop and fuel but lord help the next day it don’t want to fire off until you’ve nearly killed the batteries. A good guess would be you need to replace all your soft fuel lines, change your fuel filter, and replace the soft supply lines under the dog house


Sent from my iPhone using Tapatalk

 

[Shaun387]

If it is sucking air from somewhere, would it run fine and shut off on its own? I'm fairly new to diesels (had an 01 7.3 Excursion, but never needed to work on anything...even at 300k...lol). I was guessing if there was an air leak, it would be a problem after you turned it off and when you went to crank it later?

I’ll start by saying there’s a 95% change you’re sucking air. I come from 7.3 and 6.9 idi trucks and they are notorious for failing fuel return lines allowing air in after shutoff, will run fine and never drop and fuel but lord help the next day it don’t want to fire off until you’ve nearly killed the batteries. A good guess would be you need to replace all your soft fuel lines, change your fuel filter, and replace the soft supply lines under the dog house


Sent from my iPhone using Tapatalk

 

[Shaun387]

Spent a lot of time running this down, replacing lines, still doing the same thing. Back to getting zero fuel at the injectors. Ended up pulling the injector pump. Going to bring it to the local injector pump repair shop Monday.

Had minimal cussing pulling it.... thought it would have been a lot worse. I have to find an easier way to hood back up the 8 hard lines to the pump when I get it back.

 

[Weldman]

.

 

[NDT]

You are wise to get your pump overhauled. I like to pull and replace the pump with the lines attached like a big spider.

 

[Shaun387]

I was starting to think it would be best to do it this way. I appreciate it!

You are wise to get your pump overhauled. I like to pull and replace the pump with the lines attached like a big spider.

 

[Mogman]

Diesel engines don't mind ether, diesel engines with glow plugs do mind ether. Ether lights it off at the wrong time for placement of the piston and that's where the damage comes from.

What I said, for example the two stroke Detroits with their average 17:1 compression ratio and the older Waukesha diesels with their 16:1 can tolerate ether, the high compression diesels like the 6.2L and 6.5L with their 21.5/22.5:1 and most "modern" high speed diesels cannot, it is based on the compression ratio not whether or not they have glow plugs, not all high compression diesels have glow plugs, many industrial high compression diesels for example do not have glow plugs.
ALL indirect injection diesels need glow plugs but most direct injection diesels do not, most would be OK with an intake heater for extreme cold conditions, the reason all modern automotive diesels have glow plugs is because of EPA regulations, all that smoke when your glow plugs are not working is not allowed.
I do not run glow plugs or intake heater on my direct injection Duramax and it will start well below freezing.

 

[Retiredwarhorses]

NOS 4879 pumps are plentiful on eBay…. I would go new instead of a rebuild.

 

[Guyfang]

Did you time the IP to the engine before removal?

 

[Weldman]

.

 

[Shaun387]

Did you time the IP to the engine before removal?

I scribed a line on the IP housing / engine mounting. Hopefully this is all that needed to be done?

 

[Guyfang]

Do you have the TM for this equipment? Most IP's need to be timed to the engine so you get the IP firing at the right time.

 

[Shaun387]

I've read through TM-9-2815-237-34........when it talks about timing, it seems it's more concerned if you pull the gear off? If you're just replacing or reinstalling the IP itself, I would think you would just have to worry about final timing with a light?

Do you have the TM for this equipment? Most IP's need to be timed to the engine so you get the IP firing at the right time.

 

[kendelrio]

Sorry for the threadjack, but I have to get this off my chest.

Every time I read the title to this thread, my brain goes "I'm up, he sees me, I'm down!".


Now back to your regularly scheduled thread.

 

[Shaun387]

Figured I'd go through the whole fuel system while the injector pump is off for rebuild. Pulling the pump was more enjoyable than dropping the tank and cleaning it....

 

[Ajax MD]

NOS 4879 pumps are plentiful on eBay…. I would go new instead of a rebuild.

I'm not seeing them now.

Pardon the hijack- My engine surged noticeably a few days ago. I'm preparing for a fuel pump replacement/rebuild (just in case).
I have an old truck that was re-engined with a 6.5L in 2005 (doesn't mean that the engine is 2005) . I still have the 3LE80.

Which pump do I need:
DB2829-4879
DB2831-5209

This pump is nearly 1/2 the going price of the two listed above and claims to fit HMMWV's:
1992-2000 6.5 Mechanical Chevy/GMC Diesel Injection Pum | Huckstorf Diesel Pump and Injector Service Inc of Wisconsin (hdiesel.com)

Lastly, who rebuilds these DB2 pumps with some degree of reliability?

Thanks.

 

[Shaun387]

I'm the original poster..... haven't updated the thread because I'm waiting on my pump to come back from rebuild.

I didn't have luck in finding my specific pump number on eBay either for a NOS one.

During my search, it seemed the 2829's were for 6.2's and the 2831's were for NA6.5's. I could be entirely wrong as I'm still new to the 6.2/6.5 diesel engine myself.

I'll update with a company name of the pump rebuilder if they end up doing a good job.

I'm not seeing them now.

Pardon the hijack- My engine surged noticeably a few days ago. I'm preparing for a fuel pump replacement/rebuild (just in case).
I have an old truck that was re-engined with a 6.5L in 2005 (doesn't mean that the engine is 2005) . I still have the 3LE80.

Which pump do I need:
DB2829-4879
DB2831-5209

This pump is nearly 1/2 the going price of the two listed above and claims to fit HMMWV's:
1992-2000 6.5 Mechanical Chevy/GMC Diesel Injection Pum | Huckstorf Diesel Pump and Injector Service Inc of Wisconsin (hdiesel.com)

Lastly, who rebuilds these DB2 pumps with some degree of reliability?

Thanks.

 

[Shaun387]

Slight update.... got the injection pump back from rebuild, installed it, but didn't put the intake manifold on and left the glow plugs out. Took about four 20 second cranks for a good mist of diesel to come out the glow plug holes. Reinstalled the glow plugs, without the intake manifold on. She fired right up. Timing is off, and I don't have the right tool to properly set it, so I need to research that a bit. Going to finish putting the intake manifold back on in the next few days, since I verified the injection pump is what was actually bad all along.