E300td starting issue (yes I know!)

[bluebeasty]

Hi there

Had my E300td for a while now, but since last week I have been unable to start the car. I am aware that there are a number of threads on this, but need some advice.
So, car cranks over fine, but never actually fires up. There are air bubbles in the clear fuel lines, so I am thinking it must be o-ring trouble? I have replaced the fuel filter, carefully putting it back on, so as not to ruin the seal. I have replaced the fuel filter pre-filter and o-ring, and also replaced the fuel filter to shut off valve fuel pipe. Next i think I should try to replace all of the o-rings that are accessible. The question is, I am having trouble finding out where to get them, and sizes. Can anyone help me out with this?!
Oh and I have heard that e300td's don't like starting uphill, so have jacked the back to be higher than the front.
Am I on the right track here?
Cheers

 

[jaymanek]

Hi,

Yes look at the O rings... available from the dealer.

 

[Dieselman]

+1.

 

[bluebeasty]

So, to clarify... is the dealer the most cost effective way of getting the o-rings?
Also are they all the same size?
Cheers

 

[toolman1954]

If you have not done the O rings and pipes before, then, IMHO and experience it is better to replace all the plastic pipes, complete with their new O rings as due to the age of your vehicle then they will almost certainly be brittle be and perhaps need replacing now. It will save replacing just the O rings and then wishing you had bought the pipes as well.
Also look carefully at the fuel delivery valves on top of the fuel pump, any weeping from that area and that will certainly mean that they will need doing also.
And yes the dealer is the place to get the new pipes from, and if you ask nicely they will give you a print out of the picture where all the pipes go.
Welcome to the ""Hard to start E300 club"" do not get too stressed,-----it is curable.

 

[SilverSaloon]

there is a good kit of oriings on eBay.

Also think about the in-tank strainer.

 

[Dichtung]

From MB, new pipes complete with ends,o rings etc. are about 8 quid each.
Not really worth faffing about with o rings if your pipes are old.

The one o ring to buy from MB is the one that fits behind the cut off valve, and can be easily replaced at the same time.

Whilst the three pipes are detached from the cut off valve, (2 on top and 1 underneath) remove the 2 tork screws, (1 top right and 1 in a groove just above the electric plug) and the valve will pull straight out. On the back is a short stub of a pipe, where the o ring is easily swapped.

 

[91dm]

So, to clarify... is the dealer the most cost effective way of getting the o-rings?
Also are they all the same size?
Cheers

From what I can remember there is two different size o-rings used.
It's worth checking the hose clips on the fuel pipes that come up to the engine bay, mine was letting air in there and causing fuel to drain back.

 

[Dieselman]

From what I can remember there is two different size o-rings used.

Four iirc, counting the one behind the stop solenoid and the one under the pre-filter.

 

[91dm]

Here's the link for the kit from eBay: LINK

 

[bluebeasty]

thankyou thankyou thankyou!
I think I will go with the o-ring kit first, as the bank account isn't looking too healthy atm!
Will let you know how I get on.
Cheers

 

[Olivier]

Did you fill up the fuel filter prior fitting? It contain half liter of fuel, this is a lot...
If you didn't refill it you might kill the battery trying to get the air out.

Also look at the tank strainer. You need an Oring for it too as once you displace it it's gone. If its clogged, it'll be very hard to start the car.

Olivier

 

[bluebeasty]

Cheers Olivier, I did fill the fuel filter. But still got loads of air bubbles in the clear pipes. How easy is it to get to the in tank strainer. And what size o-ring? Thanks

 

[Olivier]

For the Oring better go to the dealer, its about 2 quid but you'll get the proper size.
The access depend if its an estate or a saloon. Easier on the Estate. A bit more tedious on the saloon.

 

[bluebeasty]

Its a saloon! BTW, do you have any mods on your e300 to run on bio, e.g. additional fuel heating. I run my td6 Range Rover on 50:50 diesel to bio, so was thinking of running the merc on 100% bio. Any thoughts?

 

[Olivier]

Saloon are more tricky. You need to take the boot carpet out.
Then unscrew the tank, four bolts.
Go under, untie the rubber pipe (that goes from the strainer) at the metal pipe connection ( its a clip) as probably the rubber pipe will be seized onto the strainer making it impossible to remove.
Now you have the dangling rubber hose, go back in the boot, lift the tank up, you can hold it with some wood on that up position, from there you see the large screw/ strainer on the left ish side, and you can unscrew it.
Then once clean put it all back together.

No Mod on that car beside bypassing the pre-filter due to excess air in the pipes due to its design, the previous one had a heat exchanger and it was helping.
She's more then happy on 25% mix and less too
I run on WVO, I don't do bio, to complicated for my little set up.

Hope it help

 

[bluebeasty]

She's alive!!! Finally got the o-rings through the post. Changed the ones I could access, and after two batteries worth of cranking managed to start her up! I really wish there was a manual lift pump & bleed system in these e300's!
Pleased to hear you are running well on wvo olivier, I will gradually introduce her to the bio, but aim to get to 100%- oh, and thanks everyone for your help!