Holy hell 🤦‍♂️🤦‍♂️

[HUMMER H1]

guys I am still in shock what happened yesterday,
driving my M1223 ( she was running beautifully) 27.000 miles on the truck,


truck was running absolutely perfect
driving about 45 mph
I noticed Rpm would not go back down
I thought IP spring broke

I tried to slow down, thankfully 12k brakes did slow down,
I Turned off the switch while in gear, it kept running,
I knew it was a run away engine.

I didnt put it in park, I tried neutral for a less than a second, engine Rpm took off
But I did it so fast and back to gear that engine didn't have time to over rev.

my Gf was with me, I asked her to switch seats and press brakes as hard as she can while truck is in gear and running

I got out opened the hood and pulled the IP wire, it kept running,

Transmission in gear kept RPM down about 2500 range
I tried to cover the air intake, it didn’t work ,
I had one option only, cut the fuel line,

after about 45 seconds engine stopped,

wow scary shit, if she wasn’t with me, I don’t know what I would of done, because if I put it in park engine would of blow immediately.

I had to call my worker to give me a ride to get my Tacoma and the tow bars to tow the humvee away,

Traumatized from this,

I never heard DB2 run away before

 

[Sjoconnor]

wow!!! great job. Hope you bought your GF a drink! keep us posted as to what you find.

Stephen

 

[Retiredwarhorses]

Been there, done that….my story.
left a paid Gig for a photo shoot, went to get on the expressway and as I slowed for traffic the engine raced, threw it into neutral, bad idea if I wanted a blown motor, back into gear to lower rpm’s, foot on the brak, I turned off the truck….no go
pulled over in park, engine red lining, pooped hood…pulled the lead for the fuel cutoff solenoid, NO GO
slammed hood, jumped in and kept going while,I tried to wrap my head around the whole thing.
At this point, my only thought was to get to the freeway on ramp and head back towards home as best I could, 45 miles to be exact.
I somehow made it to the on ramp on the expressway way by going as slow as possible with foot on the brake and timing the traffic lights so I could keep going “easier said than done”.
once On the freeway, I called the wife, I told her to start heading my way so we would meet up, being it was a Sunday, I figured traffic would be light…hell no, it was San Jose Calif and every idiot in Calif was driving that Sunday. While driving I pulled the engine cover off…my plan?
To cut the fuel filter hose with my knife…..but that plan quickly lost my confidence because that engine was soooo hot it would have probably caught fire, myself include.
As I perilously made my way towards the long grade that I had to navigate, I saw miles of brake lights for miles!
WELL, it was time to sh*t or get off the pot….i pulled over at an off ramp, engine blazing away, I used my fingers to act as a pair of pliers and pinched off the fuel line into the filter housing with everything I had….the motor sputtered and died!
A call to my wife revealed she was 15min from my location, my next call was to AAA, 15mins later the tow truck picked me up, wife arrived and home we went…

Post inspection the following day revealed that the fuel cutoff switch inside the pump cover has a hard plastic it sits in, that plastic broke into pieces and dropped into the spring loaded armature, the armature was blocked from returning via the spring tension to kill the flow of fuel and kill the engine, I removed the offending pieces and I replaced the top cover on the pump, fired the engine up and everything worked as normal.
subsequently Ive found similar pieces in other trucks I inspected ever since this event.

lessons learned?
carry a pair of needle nose in your truck, the quickest solution is to open the hood and pinch off the drain back hose on the top of the injection pump.

 

[FlameRed]

WoW!

This being my first diesel, I too was concerned about this so I posted a thread asking if this was a valid concern. The consensus of the forum was that run-aways were of no concern, and did not happen!

Now I am concerned again. I think I will install a brass valve to cut-off fuel supply or return line. I think the rubber hoses are 3/8" ID?

 

[Awol]

Good save!

Most runaways are diesels running off its own oil supply. In this case, removing its fuel source stopped it, so I'm wondering if you experienced what Retiredwarhorses did?

 

[HUMMER H1]

Shoot
Look at this

small broken piece from second solenoid
Made its way under the spring,

and shut off couldn’t turn it off, I thought it was a run away because pedal was stuck around 2500 Rpm range

basically a run a way but not exactly

 

[HUMMER H1]

Exactly on point Steve

look at that shit.

 

[Retiredwarhorses]

Shoot
Look at this

small broken piece from second solenoid
Made the befall stuck inside and shut off couldn’t turn it off

map basically run a way but not exactly

View attachment 915555View attachment 915556

Thats what happened to me!

 

[HUMMER H1]

as far as I know DB2 can’t be run a way
I was shocked to see it.

 

[HUMMER H1]

Thats what happened to me!

very very scary,

 

[Retiredwarhorses]

as far as I know DB2 can’t be run a way
I was shocked to see it.

Any diesel can become a runaway, one way is severely excessive blow by and a saturated CDR, the excess oil can combust as part of the fuel it needs to operate.
This is rare as rare comes…

 

[HUMMER H1]

Any diesel can become a runaway, one way is severely excessive blow by and a saturated CDR, the excess oil can combust as part of the fuel it needs to operate.
This is rare as rare comes…

I agree any diesel can be run a way
But it’s so rare on DB2 it’s probably 0.01% or something?
DS4 with PMD has those split second runaway feeling when it’s failing

 

[HUMMER H1]

Is the injection pump cover gasket available separately?

 

[Dieselmeister]

Is the injection pump cover gasket available separately?

Check this: 5740072 gasket

 

[Mogman]

Is the injection pump cover gasket available separately?

It is an o ring and can usually be reused.

 

[Mogman]

You will need a 5 point security torx drive bit to remove the screws, I usually set the bit in the screws and tap on them with a small hammer to help break the screws loose.

 

[HUMMER H1]

You will need a 5 point security torx drive bit to remove the screws, I usually set the bit in the screws and tap on them with a small hammer to help break the screws loose.

yes I bought that security 5 point tool,

truck is fixed and runs like a charm

To be clear, the plastic piece that broke off wasn’t from shut off solenoid, it was from the secondary solenoid that has a wire inside the pump,
I don’t know what that is for,

older humvees don’t have that solenoid in there injection pumps .

 

[Dieselmeister]

To be clear, the plastic piece that broke off wasn’t from shut off solenoid, it was from the secondary solenoid that has a wire inside the pump,
I don’t know what that is for,

older humvees don’t have that solenoid in there injection pumps
[/QUOTE]

The smaller solenoid is the cold advance solenoid.

 

[HUMMER H1]

To be clear, the plastic piece that broke off wasn’t from shut off solenoid, it was from the secondary solenoid that has a wire inside the pump,
I don’t know what that is for,

older humvees don’t have that solenoid in there injection pumps

The smaller solenoid is the cold advance solenoid.
[/QUOTE]

ahh ok
Thank you,
I should rename that piece as nightmare advance solenoid

 

[Mogman]

yes I bought that security 5 point tool,

truck is fixed and runs like a charm

To be clear, the plastic piece that broke off wasn’t from shut off solenoid, it was from the secondary solenoid that has a wire inside the pump,
I don’t know what that is for,

older humvees don’t have that solenoid in there injection pumps .
View attachment 915577View attachment 915578

Every HMMWV I have seen has the cold advance solenoid