240d primary fuel filter - PeachParts Mercedes-Benz Forum

byronspenc · #1 10-05-2003, 03:56 PM

Can i use any see-thru plastic filter? Or do i need a MB one. Where is the bleed screw for the fuel system? Am i correct, all i need to do to bleed the lines is crack the screw and pump the red handle untill no air comes out? Thanks for your help, the car is new to me and the filter looks pretty dirty, dont want to get stuck anywhere.
Byron

P.E.Haiges · #2 10-05-2003, 06:33 PM

byron,

There is no bleed serew. There is a tiny hole in the top of the secondary filter which bleeds it automatically. The injection pump also bleeds itself thru its overflow valve. Just pump the hand pump vigorously about 25 times.

I suppose any filter would work that fits the hoses. The primary filter mostly protects the fuel pump. The secondary filter protects the injection pump.

P E H

byronspenc · #3 10-05-2003, 06:47 PM

Basicly thats it, there are 2 knobs. One on the injection pump (red marked OEL with an arrow) and another on the fuel (?) pump(white, serrated edge and indented center). Which is the real piming pump?
Thanks again,
Byron

300SDog · #4 10-05-2003, 07:38 PM

You probably want a clear primary filter that lets you look at the fuel..... and it doesnt hurt to have an air pocket in their too. The way my primary filter is set up it points down - so the air pocket is on the back end, not the front.

The round knob with serated edges is the real priming pump. There's an upgrade available for the priming pump that wont leak when pumped.

byronspenc · #5 10-05-2003, 08:23 PM

Thank you all for the help. One last question(for today), Where can i get the upgrade?
Byron

#6 10-05-2003, 08:26 PM

Quote:

Originally posted by byronspenc
TWhere can i get the upgrade?
Byron

Any MB dealer. Or Fastlane. Or Rusty.

Palangi · #7 10-05-2003, 08:51 PM

Sounds like a 115 chassis 240D. The red cap marked OEL is a port for adding oil to the injection pump. The primer pump is the white handle. This car probably has the old type fuel filter, in which case the screw on top of the main filter is the bleed screw. For the pre-filter, it's probably not that critical to use the official MB one. Most people just buy the aftermarket one at the local autoparts chain store. Actually, the proper MB prefilter for that model is straight thru, not the 90 degree one we are used to from the 123's. As to the updated primer pump, it's pretty tight quarters down there. I'm not 100% sure the updated one will even fit in there.

P.E.Haiges · #8 10-05-2003, 11:21 PM

Byron,

Which type fuel filter do you have? The old type where a filter cartridge goes inside a metal can or the newer type that is a canister (similar but smaller than American car oil filters)?

I told you earlier that there was no bleed screw because I was thinking of the new type filter, but there may be one on the old style filters. I think it is in the center of the top on the secondary filter.

P E H

P.E.Haiges · #9 10-06-2003, 10:52 PM

Byron,

I looked at the secondary fuel filter on my '74 240D today and it has the later canister type filter. I was told by the PO that it had a factory replacement engine so its possible it got the newer filter with that engine. So the filter on your engine could be either type.

I had the older style filter on my 220D and 190D engines. Actually I liked the older filter better. It has a drain that can be used to get out any water and some dirt too.

P E H

leathermang · #10 10-07-2003, 08:57 AM

PEH,,, I think you may have gotten foggy on the nomenclature of the two types of filters and muddied the water in terms of your answers as a result.... usually the terms ' spin on ' and ' cannister' would be the choices...if you want to revise your answers I will delete this one...

P.E.Haiges · #11 10-07-2003, 11:49 AM

Leather,

Like I said in answer to your other post, I agree with the "spin on" nomenclature for the new type filter, but I think the old type filter should be called a "cartridge" filter since it goes into the body of the filter housing.

P E H

leathermang · #12 10-07-2003, 12:21 PM

Close, but I can't give out a cigar yet...
I think a cartridge is the type which most of us have on the oil filter arrangement on our diesels... where you put it totally into another container... like with a cartridge into the breech of a gun...
Whereas a canister provides its own sides.... but not the bottom...
And a spin on is like the normal American car oil filter... a complete case with theads which is discarded whole and replaced.
This is the same nomenclature which my Ford tractor dealer used when asking me about the fuel filter on my tractor....canister/spin on...