Engine shut off...
I've got a 92 300GDS that runs smoothly except for one problem. When I turn the engine off, it keeps running for a few seconds and then dies with a big shudder.
Any suggestions?
Maxwell. It could be one of a couple of things really. there are not many electrics on the diesel G but one of them is the cut off solenoid as you switch off the solenoid looses its energy and cut the fuel Trouble is i dont know exactly where it is on the 463 version also it could be a worn ignition block or dirty contacts so as you switch off the contacts dont respond immediatly
I had a 76 240 D that had the same problem. Turning off late was just a slight delay with the actuator on the injector pump. I never really thought of it as a serious problem.
The violent shaking was due to carbon build up inside the head. I ran several cleaners with the fuel until the carbon was removed. The engine shaking was reduced. That engine is still running at 240k miles. Adding a quart of oil to the tank when you fill up will help the carbon build up also. :wink:
I've had a similar problem on a few vans in the past.. I'm no mechanic,,and it was a good while ago,, so i'm gonna have a hard time explaining,,, theres a small rubber diaphragm, that releases compression when you turn off the engine,, that most probably needs replacing,,, it's an east DIY job,, take's about 10 minutes,, sorry, i can't describe it any better,,(and have no idea where it is on a G) but hopefully may put you on track... If it is the same problem,, it needs fixing soon, as the engine will slowly take longer to stop,, eventually you'll have to resort to stalling the engine..
POSTED FROM AN EMAIL BY ROLY:
There is a lever on the side of the injection pump which is located under the intake manifold on the RHS of the engine . It has all the fuel lines going to it . The lever has a red sticker on it which says STOP on it.(or it did when new) If you are not tall you need to get you head right over the engine to clearly see it.Push it down with you finger or screwdriver (no force required) and the engine will stop.It cuts the fuel supply, which stops a diesel.
When the ignition key is turned off there is a solenoid which deactives and allows the lever to move fully downwards which stops the engine. It then returns to its original position ready for starting.
So there are 2 possibilities with you problem. Either a fault with the solenoid or a fault with the pump. If pushing down the lever manually immediately stops the engine then the solenoid is faulty (or the electrical connections more likely)
theres a small rubber diaphragm, that releases compression when you turn off the engine,, that most probably needs replacing,,, it's an east DIY job,, take's about 10 minutes,, sorry, i can't describe it any better,,(and have no idea where it is on a G) but hopefully may put you on track... If it is the same problem,, it needs fixing soon, as the engine will slowly take longer to stop,, eventually you'll have to resort to stalling the engine..
Well I think Mark was right. In addition one of the tubes connected to it had come disconnected. Seems slightly better for the moment. Am just awaiting some new one way valves to try an replace the existing ones and see what happens.
Well I think Mark was right. In addition one of the tubes connected to it had come disconnected. Seems slightly better for the moment. Am just awaiting some new one way valves to try an replace the existing ones and see what happens.
Max:
It could also be that the "Stop" device at the injection pump which is vacuum actuated does not receive sufficient vaccuum because i) the vacuum pump is faulty, ii) the switch at the steering lock is faulty or iii) the lines driving the vacuum from the pump, via the switch to the injection pump are leaking.
As always, I would start with the "cheapest" to the "most expensive", i.e. check iii) first then ii) and finally i).
Good luck!
I don't own a g-wagon but own and have owned 300d's 307d and 409d. To troubleshoot your problem you need to pull a vacuum on the shut off valve with the engine running. If it shuts off, the problem is not with the valve but somwhere else in the vacuum system. Here in the US we use a tool called a Mity Vac which pumps a vacuum (it can also be used to bleed brakes). If it's somewhere else in the vacuum system, you can use the Mity vac to trace it down. In the vans, the vacuum system is very simple. In the 300d's vacuum runs just about everything so it gets more complex. I'm suspecting the g-wagon is more like a van.
Regarding the shut-off problems.
The engine run-on is often due to the buel shut off not completely shutting down. As others have noted, shtting the engine down mannually will likely tell you that everything else is functioning OK. And, that there is a vaccum leak somethere. Sometimes putting a light weight oil on all the pump linkcage helps. Ckeck all linkage and vaccum lines.
Best of luck.
If engine fails to shut down clean, then problem is in the the fuel sut down solenoid or spring loaded vacuum activated valve. if engine start/shutdown is electricaly controled then trace to solenoid.
15 minute job
Bill Moss
There is a lever on the side of the injection pump which is located under the intake manifold on the RHS of the engine . It has all the fuel lines going to it . The lever has a red sticker on it which says STOP on it.(or it did when new) If you are not tall you need to get you head right over the engine to clearly see it.Push it down with you finger or screwdriver (no force required) and the engine will stop.It cuts the fuel supply, which stops a diesel.
When the ignition key is turned off there is a solenoid which deactives and allows the lever to move fully downwards which stops the engine. It then returns to its original position ready for starting.
So there are 2 possibilities with you problem. Either a fault with the solenoid or a fault with the pump. If pushing down the lever manually immediately stops the engine then the solenoid is faulty (or the electrical connections more likely)
Ok call me slow, but for the life of me I can not find this "stop lever". Does someone have a photo of it?
And am I correct in assuming that the spring loaded vacuum activated valve are those 1" diameter off white barrels connected into all the tubing on the right hand side of the engine when facing it from the front?
The little white round things are in line filters. The shut off valve is in a black box on top of the injector pump with electric cables goind to it
Sorry but I am a serious automotive novice. Here is what I have:
1. Wouldn't open without breaking.
2. Now I presume that this is what everyone is refering too, but I coulnd't figure out how to open it without breaking it.
3. Just had wires in here
4. These I've ordered new ones to replace since I've been told they should be replaced regularly. 4a was disconnected and I just reconnected it. I've been told that they are one way valves.
If you bring it to Slab common Bordon Hamshire tomorrow I will have a look at it in between off roading
Bill Moss
ok finally figured out why I could never see the stop lever, when the engine is running the lever is in a perfectly vertical position that makes it hard to see when looking from the front or even top. You would almost have to be looking from inside the car to see it, albeit the hood would be in the way.
Anyhow the engine stops smoothly when I push the lever, so I'll start checking the other tips. Starting with the vacuum.
thanks.
I Have a much older 5 cyl 300 D which did the same. If your engine cutout is controlled by vacuum the problem is worse if you pump your brakes before switch off ie you use up your vacuum and this causes a longer delay before you have enough "suck" to shut the motor down.
A quite simple repair to the vaccuum pump should fix this and also makes a big change to braking and makes your right leg slimmer.
Alternatively park the vehicle against a stout tree, engage a high gear and drop the clutch taking care not to engage any diif locks etc as this good German may take this as an instruction to climb said tree. The motor shuts down quite quickly using this method.
Andrew
Iv'e just fixed two G's with the same problem.
The first one was a leaking vacum control unit on top of the fuel pump and the second ( fixed today) was a fractured vacum pipe.
If you still need help send me an email and i will give you a photo and details of how to fix it.
Bill :)
Max:
It could also be that the "Stop" device at the injection pump which is vacuum actuated does not receive sufficient vaccuum because i) the vacuum pump is faulty, ii) the switch at the steering lock is faulty or iii) the lines driving the vacuum from the pump, via the switch to the injection pump are leaking.
As always, I would start with the "cheapest" to the "most expensive", i.e. check iii) first then ii) and finally i).
Good luck!
Max:
Here's a drawing to explain what I meant in my previous posting. I had to replace a valve in the steering lock (part A0004600284) for £10.38 + VAT
BuillionBill, it would be great if you could post pictures here on the forum on how to fix it, as a few people I have spoken to have similar problems. If you can't post pcitures, send them to me and post the steps, then I will add them to your post. Thanks.
Mortinson - in that diagram, which part did you replace? 95?
Thanks
Yep. This diagram is from the EPC (Electronic Parts Catalogue). I bought 56 first but it wasn't faulty and has it returned. Then replace 95 and everything was hunky-dory from then on.
By the way, I am trying to secure a safe and cheap way of securing factory MB EPC's. So watch this space...
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Thanks guys, that gives me lots to try. Will hopefully look at it this weekend.