Shut down and stayed down

[RickJ]

HELP!

Hi all

I own a l400 with the 4m40 diesel. I use it as my daily driver. Yesterday while running some errands, she stalled while driving along a main road at ~40km/hr. I was able to pull off and into a parking lot. I figured it was an air in fuel issue as it just seemed to loose power and shut down. I immediately pumped the primer and tried to restart without any luck.

I had a 17mm in my tool kit and so I cracked the injector lines, re-primer and turned it over again. No fuel at the injectors. I realized at this time that it was most likely a cut off solenoid issue. I decided to get her towed home at this poi t.

Once home I searched for the location of the solenoid. To my surprise I found two. One near the fuel lines, covered with a black boot, and one further up near the diaphragm housing, covered with a green boot.

The lower I figured is the cutoff solenoid. I had to fabricate some sweet tools (cut up and rewelded 24mm wrench) to be able to remove it. After removal I tested that there was power to the supply wire to which all seemed normal. I also own a 13v power supply to which I used to test the solenoid. Sure enough when powered the plunger pulls in and all seems normal.

I also removed the upper solenoid (again creating a 3/8 drive 24mm socket using a lathe and welder, as the room available did not allow for a the 1/2” drive ratchet to fit with the original 1/2” drive 24mm socket). This solenoid was different in that it did not have a visible plunger. It is fitted with a screen inside to which I cleaned thoroughly of what looked like lint. Bench testing seemed fine due to the sound of internal clicking. This fellow does not seem to have supply power at the wire however, I have directly jumped the battery to each of these two solenoids to ensure they were powered and still no fuel supply to the injectors

Also to note, I started having the typical front seal issue last March (2018) and so in April I removed the pump and replaced it. I have had zero issues with the van since then until the this happened.

Has anyone else had this issue and been successful in determining what the root cause of failure actually was?

Thanks in advance.

[Growlerbearnz]

Sounds like you've fixed it, but for curiosity did you check the resistance of your old cutoff solenoid? It should be 48-60 ohms. If it's less (or open circuit) then the coil's failed.

The upper solenoid with the green boot causes the injection timing to advance, to help with cold starts and running.

[RickJ]

Hi Growlerbearnz, Thanks for the reply

Nope not fixed. Worse actually...

While messing about with it yesterday I all of a sudden noticed a crack in the front cover in way of the inj pump timing gear area. I immediately removed the pump to find that the nut had in fact backed off and so had the timing gear. Somehow the key was still held captive. None of this makes much sense to me. I understand that if the gear had unmeshed with the other timing gearing , this would stop the pump from being driven and all would make sense on why there was no flow to the injectors. The key sits fairly loose in its counter bore of the shaft and so if the gear had completely walked forward, my guess is that the key would now be sitting in the engines sump. It was not. On the inside of the front cover there was a small bright circle where the nut had rubbed against. It held the nut from also becoming lost into the sump. Not sure if it was this force from the nut or the gear itself that did the case damage. Other than the case damage, the only other damage found was that the first 2 threads on the nut were slightly marred from coming up to a hard stop on the case. This was taken care of with a tap. It is now all re-torqued to the pump shaft with some high strength red loctite as a backup plan.

As for the crack, I was able to mostly tap it gently into place with a small ball pein hammer, and applied a fair layer of DEVCON plastic steel epoxy to keep any oil inside the case. Hopefully this will take care of this.

I did not notice any of this until day two of troubleshooting and so I cannot tell if this is the failure cause , a late stage result, or a result of something else completely unrelated to the original issue. The timing chain, tensioner and other timing components all seem unaffected from what I can tell. I have not re-timed the crank/cam yet to refit the inj pump as it is raining today. Bad excuse/reasoning I know...

As for the solenoid, That was my first thought to all of this drama. I completely removed the spring and plunger to test if there was flow to the injectors without it. This would at least prove whether the solenoid was NFG. This didn't change anything.

Anyone else suffer this plight?

[RickJ]

Issue resolved.

I retorqued the inj pump pulley back home and added some red high strength loctitie to the threads in hopes to never suffer this issue again. I used a ball pein hammer to carefully tap the cracked front housing back into place as best as possible. Using some 2 part Devcon plastic steel epoxy, I filled in and covered the crack in hopes of keeping the oil in the engine. So far it seems to have worked well. I refitted the inj pump and timed to the original position.

The strange part is after doing all of this, and priming the system (withmuch less vigor than previously), I had fuel to the nozzles on the first start attempt. I’ve now put around 60km on her without so much as a hiccup. Time will tell but she seems to be back to normal. The only thing I can day is that other folks suggestions of the filter head being suspect could be the culprit.

[Khrolar]

Glad you figured out the cause! That would had be scratching my head for days!

[Khrolar]

Glad you figured out the cause! That would had be scratching my head for days!