HMMWV injector pump bad or??

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Sundowner9000

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I know there's a bunch about no starts and IP's but I'm trying to find out for sure before I spend a ton of money.
M998 won't start, used to start on a dime. Getting fuel to filter and to IP. Cracked an injector line, no fuel. Getting 24V to wires on top of IP. Ran a hot wire to each post and front one clicks just fine. Rear post I can barely hear it click, not as loud as front post when I touch it with hot wire. Last time it actually started it cranked a few extra times like maybe losing prime. It sat a month and now it wont fire at all. Any help appreciated greatly. No fuel leaks BTW that i can find
 

NDT

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And you are 100% sure the glow plugs are glowing? Make sure all that works right before pulling the injector pump.
 

Sundowner9000

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I replaced all the glow plugs thinking that was the issue. It tried to fire with a shot of starting fluid, and I found out by reading later that's not wise with these but that was before replacing glow plugs. When I took injector line off and crank it there's no fuel coming out of the line.
 

NDT

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Is your start box clicking and voltmeter dipping as the glow plug system cycles? Don't think about replacing the pump until you are sure you are getting glow.
 

Sundowner9000

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I believe so. When I turn the switch on I can hear the "thunk" and the volt meter dips down and up like it seems to be correct. I bought this about 8 months ago and was starting it weekly until the last month it ran. Haven't driven it down the road so I can't say that it was driving different. It literally quit starting right up over night that's why I'm having a problem believing IP went bad. Not sure if fuel shut off solenoid inside pump is stuck off or something.
 

Sundowner9000

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Going to open up a few more injector limes shortly and crank to see if maybe it lost prime somehow and won't bleed out. The IP has a sticker on it from 2005 so it's somewhat newer but I know that doesn't mean it's not bad
 

NDT

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If you have plenty of pressure on the injector pump inlet, the run solenoid is engaging, and no diesel spurts out of the injector lines, sounds like you may be right about the IP.
 

Sundowner9000

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I was hoping I was wrong. It's definitely got pressure to the IP. I think I was hoping solenoid was bad and stuck closed. I've read to use jumper wire to those 2 top posts and listen for click. The front post I can definitely hear click, the rear one I have to put my ear to it to hear the slightest anything. So thought maybe that's where it might be telling me it's stuck but I'm sure that's being wishful. I will try to crack those lines open and crank to be sure there's no flow. I greatly appreciate the help gentlemen. Been trying to track down that specific number pump DB2829-4523 but not having much luck. It looks like there's several numbers just don't want to buy the wrong one especially being 24V
 

NDT

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My recommendation is to pull your pump and have a local reputable injection repair shop rebuild it. They will know exactly how to set it up from the Stanadyne numbers on it. Usually runs around $400 here in Houston.
 

1 Patriot-of-many

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Put a piece of clear line where the small section 2?3? 4? inch of rubber is coming out of the front of the pump to the return line.... See if you have any movement of fuel when cranking. Your wait light coming on for about 5-7 seconds then off? Check your valley, is it dry? I had a bad seal when I bought mine, Could see air bubbles in the return, valley was wet.(that's an understatement, had a good fast drip filling the valley with fuel.
 
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Sundowner9000

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It's worth a shot. Opened up 2 more injector lines and cranked and still no fuel. The valley is dry. Yes my wait light comes on for anywhere from 5 to 10 seconds
 

1 Patriot-of-many

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If you don't see any movement of fuel it's either something in the pump(since you are getting fuel to the pump) or check valve stuck? in the return line from what I've read. Good luck.
 

diesel dave

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The fact that it "happened almost over night",leads me to believe it's the fuel shutoff solenoid. I've had a couple of these fail in cucv's I've owned. Easy to change and not that expensive-at least not the 12v. I'm not an electrical guy,and don't recall how to check them,so I don't whant to steer you wrong with bad info. Maybe one of the experts will respond on how to check.
 

Sundowner9000

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Dave, that's what has been ringing my bell this whole time. I definitely won't day an IP can't go out like that but it literally was overnight. When I was starting it just to charge batteries, it was for 15 minutes at a time and it started like an old Ford with the points set perfectly, just a flick of the switch. The last time it started it cranked for 3 seconds and then fired which was uncommon and now it won't even try. Like a switch was turned off. Was thinking about replacing that before pulling UP but I realize that may be just wishfull
 

1 Patriot-of-many

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Dave, that's what has been ringing my bell this whole time. I definitely won't day an IP can't go out like that but it literally was overnight. When I was starting it just to charge batteries, it was for 15 minutes at a time and it started like an old Ford with the points set perfectly, just a flick of the switch. The last time it started it cranked for 3 seconds and then fired which was uncommon and now it won't even try. Like a switch was turned off. Was thinking about replacing that before pulling UP but I realize that may be just wishfull
Simple enough to check. disconnect the line at the return line, crank it. Fuel comes gushing out, it's not your shutoff. Fuel doesn't come out you're zeroing in on something in the pump.
 

Sundowner9000

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Unfortunately it's the IP on it bad. I'm ordering a new one tomorrow. I had badly hoped it was anything but the IP but all roads point to the expensive fix I'm afraid
 
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