Hymer Mercedes - Stranded in Ireland

[Hymer Madness]

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

 

[neilydun]

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.

Would glow plug failure cause a problem, when its so warm ?
I have a 2004 Merc with a glow plug out, and the coil light continues to show once started for about a minute. The car starts fine.
Mine also has an intermintent ESP fault, wich could be the same. Does not effect anything really.

 

[ChrisL]

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.

I don't think that fits with it initially running but then getting harder to start until it wouldn't start at all, I had a pump fitted one tooth out but it still ran okay, but was noisy. I'm not familiar with how these pumps are timed, I suppose if manual adjustment is available by turning the pump then maybe if the securing bolts weren't tightened properly the pump might move.

 

[ChrisL]

Would glow plug failure cause a problem, when its so warm ?

If they're all not working it might not start, could be the glow plugs relay maybe?

 

[Landy Andy]

I don't think that fits with it initially running but then getting harder to start until it wouldn't start at all, I had a pump fitted one tooth out but it still ran okay, but was noisy. I'm not familiar with how these pumps are timed, I suppose if manual adjustment is available by turning the pump then maybe if the securing bolts weren't tightened properly the pump might move.

That’s my thinking if mechanical injectors. Pump timing adjustable, not fully tight, and has become more and more missed timed.
If glow plugs, it would run after it has run on easy start for a while.

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[chaser]

We are all just clutching at straws really but it is 1998 so can't be that complicated but we have got some tractors that won't start without heat no matter how hot it is.
And the clincher is that it wasn't starting before they started doing it but if it's in a garage they should know all the things that have been suggested.

 

[qsydavid]

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

I also have S660 1991 so no diagnostics and had similar problem. Did you have any unusual events from your dashboard preheat indication, eg came on when engine running or didn’t go off after a few seconds ? I changed 3 of the 5 glow plugs and problem solved,. Ideally change all 5 but first two cylinders very difficult to reach. (Also changed the same bits you have done and scratched my head a few times).
I am in France near Cherbourg if you can get this far .
David

 

[Sleeveless]

OM 400 engine ???? don't think so ... But from memory, the aluminium fuel filter housing / mounting used to distort/ crack on OM602 and similar engines allowing air to enter the system around the cannister filter seal , worth checking that and all the associated plastic feed pipes and connectors especially the "O" rings. Even a tiny amount of air in the fuel system between pump and injectors will prevent starting on that motor. Think it also has a heat exchanger in the fuel line somewhere, also with plastic quick connectors.

 

[WESTY66]

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.

I’m thinking this too, why did you feel the need to have a new pump and crank position sensor? If it wasn’t starting properly before I’d be having a compression test!
I had a golf many years ago, it would start with easy start and a tow, but not on the starter, turned out the compression wasn’t very good. Re rung it and valves lapped in, started on the key

 

[chesterfield hooligan]

That's one of the problems using easy start the knocking when starting with easy start is the higher combination pressure which shatters the piston ring's, the compression ring's are made from cast iron making the engine addictive to easy start.

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[thehutchies]

OM 400 engine ???? But from memory, the aluminium fuel filter housing / mounting used to distort on that version and allow air to enter the system around the cannister filter seal , worth checking that and all the associated plastic feed pipes and connectors especially the "O" rings , even a tiny amount of air in the fuel will prevent starting on that motor. Think it also has a heat exchanger in the fuel line somewhere, also with plastic quick connectors.

I had an old Mercedes with the same symptoms, and this was the problem - air being sucked into the fuel lines past 20 year old O rings. Fairly easily replaced.

 

[Sleeveless]

I had an old Mercedes with the same symptoms, and this was the problem - air being sucked into the fuel lines past 20 year old O rings. Fairly easily replaced.

As an official dealer ( or stealer) as some would say , we used to replace all the plastic pipes under the inlet manifold , this used to sort the non start out . Pipes relatively inexpensive . If you did one , another would fail shortly after , a bit like chasing light bulbs.....

 

[chaser]

I also have S660 1991 so no diagnostics and had similar problem. Did you have any unusual events from your dashboard preheat indication, eg came on when engine running or didn’t go off after a few seconds ? I changed 3 of the 5 glow plugs and problem solved,. Ideally change all 5 but first two cylinders very difficult to reach. (Also changed the same bits you have done and scratched my head a few times).
I am in France near Cherbourg if you can get this far .
David

That's what I can't understand with this. If starting was getting more difficult the first thing you would do is change the glow plugs before anything else it might be . This hasn't been mentioned, why go to all the trouble and expense of an injection pump til the heater plugs had been changed.

 

[SafetyPete]

Its mentions all engine electrics checked at a cost of £1000

Pour boiling water over the inlet manifold, then try starting, if it starts then your problem is heater plugs. Have the garage checked the voltage to the buzzbar?

 

[ChrisL]

Sadly the OP hasn't subscribed, so I guess we'll never find out what the resolution was.

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[wizzo]

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

Sounds very much like faulty glow plugs or glow plug solenoid.

 

[Tantalus]

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

A few years ago the return pipes from the injectors failed. I understand it's a common problem. 2.8 Merc 2002. Maybe?