w202 c250td non starter, any input appreciated

[monoblock202]

Hi everyone, i've been lurking on this site for a while now trying to fix the problem with my w202. Thought I had it solved but alas it's happening again.

I had an air leak in my fuel system (c250td) and after reading similar stories here, I replaced my clear fuel pipes. Car started afterwards, next morning it didn't, No joy.

I then replaced the o-ring under the pre filter and also the fuel filter. Car started afterward but didn't next morning, No joy.

Then I fitted a new o-ring on the banjo fitting at the back of the injector pump and a new o-ring behind the stop solenoid, I had the inlet manifold off at this stage and replaced all the o-rings on that as well (I know this wouldn't directly affect my problem but I replaced anyway as they were hard as plastic). These were all genuine MB parts as well.

Success! Car started on the button everytime,,,, for a couple of days

It really was like a lotterry every morning wether the car would start or not, the i found out that if i parked downhill the car would start every morning, so I fitted an in-line pump that also acted as a non return valve.

This pump was wired into the heater plugs, my thinking was the pump would pressurise the system and force the air out only when it needed it then knock off with the plugs.

Still cant park uphill lol,, what a car If I park uphill she wont start so It was always downhill.

This practice was alright until 2 weeks ago, I left my girlfriend to work at 6.30am then parked up and jumped in again at 9.30, car started but drove 50 mtrs then died completely but it showed the e.p.c light before her last breath.

I sent the car to my mechanic and got it back on Saturday past, and it run fine then wouldn't start again on sunday leaving work

I am utterly frustrated with this car now and I really don't want the hassle that comes with owning it, I've spent so many hours nursing this thing to life I feel like scrapping it!!

Sorry for the long essay, but I've tried to include everything, If anybody has any input at all I would very greatfull indeed

Ryan

 

[monoblock202]

Sorry I forgot to mention that there was diesel dripping from the stop solenoid and that the 4 pin electrical socket was soaking inside, if I dried that then opened an injector the car would eventually start if the battery held out. I replaced the o-ring behind the solenoid as I thought that I might have damaged it installing it but it was fine and there is still a slight seeping.
Ryan

 

[Dieselman]

Look for air bubbles when revving hard from idle. Wherever they appear first is after the leak. Suspect either the fuel heater or the rubber to plastic pipe unions at the rear of the engine bay.

Is the seeping from the stop solenoid or from above? If above suspect the delivery valve seals.

 

[monoblock202]

Thanks for the reply! It seems to be seeping from the solenoid itself, as if through it like the o-ring is damaged but twice I have replaced it and twice it looks like I didn't need to.

Would it be wise to replace the delivery seals and see how it performs?

Car still wont start now, even with a portable booster pack, she run that flat too lol.

Ryan

 

[a111r]

I would leave the delivery valve seals alone as it sounds like the stop solenoid, if you can be sure that's the actual leak site.
The O ring usually fails by going 'square' over time, i.e. 14 years.
Did they sell you the right size?

 

[monoblock202]

started

Got the car started tonight with a tow, funny thing is, it always starts with a tow but as you can imagine, thats not really practical.

The pipes below the solenoid are soaking with diesel when i checked, is it unheard of for the actual solenoid to crack or leak?

a111r, I'm assuming that they are the right size, they were both identical and I had to quote my chassis no when ordering them (Charles Hurst Mercedes Belfast) I don't have the part no anymore though as I binned the packaging a while ago.

Ryan

 

[guydewdney]

replace the pipe under the stop solenoid?

 

[monoblock202]

c250

Hi Guydewdney, I have replaced all the pipes maybe 5000 miles ago, it seems like it is leaking from the solenoid itself even though the seal seems good I'm stumped.

Ryan

 

[Dieselman]

It probably is the solenoid, then.

 

[monoblock202]

Part no's

Just another question, does anybody know the part no's of the two o-rings at the ends of the solenoid? I stripped the solenoid and found that these two o-rings seem hard and one a little cracked, could be the problem, car is currently parked on my drive and I'm seriously starting to like the missus xsara even though it just split the exhaust just back from the manifold

 

[monoblock202]

solved

problem solved! Piece of ****e is now swapped and wrecking somebody else's head, swapped it for a proper mercedes, an '89' 190d with 186,000 on the clock, thanks everyone for your input and help but I've admitted defeat lol

 

[trapperjohn]

Better luck with this one. On of my very best Mercedes was my K Reg 2.5 190D. Only sold it as I just could not get comfy in the divers seat due to a hernia op.

Wish I'd kept it? Nah I have had a wonderful assortment of Mercs since.