Fuel filters - e300td

[johnsco]

I did a job over the weekend - Changed the main fuel filter and the pre-filter on the E300TD.
Not difficult.
I had the parts, including the replacement O-ring seal for the pre-filter housing.

In the box with the main filter cartridge, were two O rings ... One slightly larger than the other.
I used the larger O-ring to replace the one on the hollow bolt.
The other one appeared not to be required, so I refitted the parts in the same way they came apart.
The engine required a fair bit of cranking to get it to bleed the air out of the injectors.
It gave me a few rude messages on the dash.
But, eventually, it fired up and all is running well.

Except .........
Looking at the diagram on the Russian site suggests that both O-rings should have been fitted.
I don't know where the small one would go.
I didn't see it during dis-assembly.

Can anyone advise me please.
I've got the same job to do on the other E300TD in the next few days.

Thanks in advance.

 

[AANDYY]

Fill the next filter with fuel, so little cranking is then required on start up.

Dunno about the O ring question.

 

[johnsco]

Thanks Andy
I'll sure remember to fill the filter before fitting.
I didn't have a spare can of diesel this time, or I would have done so.
Cheers.
Johnsco

 

[Olivier]

Defo as Andy said you need to fill up the filter or you might kill the battery with all the cranking needed.
The second O-ring ( small) is not needed. It just come with some filters as some cars needed but not on the E300TD

 

[johnsco]

Many Thanks Olivier.
That's what I thought.
My doubts arose when I looked at the diagram on the Russian site and it actually shows 2 O-rings.
Thanks for your help.

 

[SilverSaloon]

Yes both o-rings are required on the models that have the fuel shut off on the filter bolt itself. (ie 606 W124 models).... later W210 606 ones have just a bolt there and require just the larger oring. i think anyway - i use both orings on mine as its a W124

hope this helps

derek

 

[johnsco]

Thanks Derek.
That explains it.
I just had that horrible feeling that I'd missed the trick somewhere.
But all is OK.
Cheers.
Johnsco

 

[krimat2005]

the second o-ring is for oil drain plug, should be changed at oil change.

 

[SilverSaloon]

the second o-ring is for oil drain plug, should be changed at oil change.

He's talking about the fuel filter, not the oil filter.

the oil filter comes with the relevant orings/washers for oil change only... the fuel filter comes with whats needed for that and nothing else.... as far as all the filters i've purchased before are concerned (genuine MB filters)