Hymer Mercedes - Stranded in Ireland

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Hymer Madness

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MH
Hymer S660 Mercedes
Dear Members
1998 Hymer Mercedes S660
2.9L OM400 Bosche Manual Pump

Not starting !
Does anyone know of a classic Mercedes Hymer guru mechanic (UK, Europe, Ireland) that may be able to shed some light on what could be wrong OR do any members have any suggestions what the issue could be.

Fully reconditioned Injector Pump fitted 2 weeks ago €1400
New Crankshaft Position Sensor fitted 4 weeks ago €300
€1000 spent on checking all electrics to motor -all ok
Nothing showing on Diagnostic Tool
Dash has one warning light - can’t recall but something like E** ?

Will run on EasyStart

At present thinking replace Control Box ?
Check fuel supply pressure ?

Had bumper off for repair at body shop BUT was turned around in yard after this. Started normally. Did sit at body shop for 2 months.

Starting had become progressively more difficult during storage over winter.

Any information would be much appreciated.

Regards
Dan
 
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Hate to be cynical but can it be coincidence that 2 weeks after reconditioned pump fitted it won’t start?
Is there a way to check that fuel is being pumped to where it should be going? Excuse my naivety, I’m thinking along the lines of removing the pipe at the end and see if diesel spews out.
Good luck.
 
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If it’s sat in a yard for two months it could be fuel has seeped back to tank, possibly due to filter leak.
Could be a build up of contaminants in the filter, had it a long time ago on a vehicle that they used dodgy diesel in!

Try a temp fuel line, from filter to engine even a small bottle will do, if it starts and runs next step is filter
 
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Has it got an electric lift pump that supplies fuel from the tank to the injector pump ? These sometimes fail/stick or the electrical terminals can corrode stopping it from supplying fuel.
Get yourself one of these for a quick way of making sure you're getting fuel to the injector pump.

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Diesel Bob at Preston may be able to help, also check out his website as there are reviews of different engines and if they have common problems. In your case I would be looking for leaks, either diesel leaks or air getting sucked in.

Diesel Bob UK Ltd

https://g.co/kgs/HsnKmZR
 
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I'd also check:

Water in the fuel - As the van was standing around for months, then water evaporates out of the fuel, condenses on the side of the tank, and then drips back into the fuel and should sink to the bottom, which is where the fuel line out is located.
So you could be trying to run the engine on a diesel/water mix.

The solution is to always fill the tank to the top when you know it's going to be unused for a few months, but fuel does go 'off' so if a couple of months is actually a year or more you are better off draining the tank and allowing air circulation by leaving the fuel cap off (if that is a safe option, where nothing, rain, insects, lit cigarettes etc can get in )

Also: Just checking, it is diesel you have in the tank and not petrol ...... :whistle:

As suggested post #7 above, fill up a clean fizzy pop bottle with nice new clean diesel,
get a meter or two of plastic hose from an aquatic shop, a few micro jubilee clips
and then attach as close to the engine as you can get.

If the engine runs, you then work backwards towards the tank, section by section.

FYI - This is a filthy job, diesel will go everywhere.
Needs to be done outside otherwise the fumes will give you more than a headache.
 
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if it has a in tank pump its probably worth thumping bottom of tank a few times which might shock it into life

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chaser said:
I suppose you have loosened the injector pipes at the injectors to bleed it up and see if diesel is getting there.
Click to expand...
Hi Chaser, Thanks. Yes getting fuel out the injectors when lessened. Please note it’s not me doing the work, it’s in a garage at present running out of options so hoping someone might have a left field idea re solenoid or hidden plug or something. At present most are focusing on fuel delivery issues or timing which I think could be right.
 
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chatteris said:
if it has a in tank pump its probably worth thumping bottom of tank a few times which might shock it into life
Click to expand...
Hi Chatteris, This been wondering where pump is located. Hopefully garage can check this. Regards
 
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Brains said:
I'd also check:

Water in the fuel - As the van was standing around for months, then water evaporates out of the fuel, condenses on the side of the tank, and then drips back into the fuel and should sink to the bottom, which is where the fuel line out is located.
So you could be trying to run the engine on a diesel/water mix.

The solution is to always fill the tank to the top when you know it's going to be unused for a few months, but fuel does go 'off' so if a couple of months is actually a year or more you are better off draining the tank and allowing air circulation by leaving the fuel cap off (if that is a safe option, where nothing, rain, insects, lit cigarettes etc can get in )

Also: Just checking, it is diesel you have in the tank and not petrol ...... :whistle:

As suggested post #7 above, fill up a clean fizzy pop bottle with nice new clean diesel,
get a meter or two of plastic hose from an aquatic shop, a few micro jubilee clips
and then attach as close to the engine as you can get.

If the engine runs, you then work backwards towards the tank, section by section.

FYI - This is a filthy job, diesel will go everywhere.
Needs to be done outside otherwise the fumes will give you more than a headache.
Click to expand...
Hi Brains, Thank you for the extensive overview. All valid points. Will add this to the list for the garage to check out.
Points of note:
It was getting harder and harder to start during winter storage often wearing down the battery to zero and needing a jump starter put on it
2. When body work was done, it was started and turned around in the yard. It then didn’t start 3 weeks later and hasn’t since unless on EaszyStart
Thanks

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Is there a strainer on the fuel pickup in the tank and is it blocked? Unfortunately you have exceeded your free posts so to ask more questions you will need to subscribe, it's only £20/year and you may be able to benefit from discounts from some suppliers.
 
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Hymer Madness said:
Hi Chaser, Thanks. Yes getting fuel out the injectors when lessened. Please note it’s not me doing the work, it’s in a garage at present running out of options so hoping someone might have a left field idea re solenoid or hidden plug or something. At present most are focusing on fuel delivery issues or timing which I think could be right.
Click to expand...
If you have diesel coming out of the injectors it can't be anything to do with fuel, got to be timing.

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Btw why was the injection pump replaced? Is there something else that was already wrong with the engine not the pump.
 
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What diesel system is it. Electronic injector, mechanical, common rail??

Can’t find any info on “OM400 Bosch Manual Pump”

Do you have any alarm or immobiliser fitted?

What IS the warning light “E**”
 
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Reading through all this again , this engine had already got something wrong with it that was probably nothing to do with the injection pump.
Getting harder to start in the first place would straight away point to heater plugs which haven't been mentioned so probably still got the same ones that weren't working to start with, and heater plugs failing will put all sorts of warning lights up, other than that all it can be is the injection pump put on out of time as if the engine runs on easystart the engine timing must be ok.
 
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If fuel is getting to the injectors then it can only be the pump timing is out and seeing as the pump has just been overhauled and the problem has just started then it has to point to the injector pump timing being out when the pump was refitted
It doesnt take much for timing to cause problems.
 
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