Dear friends:

I've just gotten a 1981 Mercedes 240D (Manual) and will receive a Haynes W123 repair manual next week. Since I'm a diesel newbie (even though I'm pretty familiar with gasoline cars), I really need your help in identifying the various parts in this diesel car.

Please take a look at the attached image and give a brief description of each part (numbered in the image) and its corresponding function.

Thank you in advance for all your precious help.

Best regards,

Eric

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Template (Number - Part Name - Description)

1 - Bush's personality: war-like
2 - Bush's interest: huge tax cuts for super rich people
3 - Bush's daughters: 2 drug addicts
4 - Bush's geography and history knowledge: none
etc.

Attached Thumbnails

 

1 fuel return hose
2 injector fuel line
3 injector
4 ALDA capsule
5 booster vacuum hose
6 main fuel filter
7 inline fuel filter
8 fuel feed hose
9 injection pump

#1 - Is improperly hosed fuel return from individual injectors. The fuel is used for lubrication of the moving parts in the nozzle and passes from the high pressure side past the pintle out of each injector.

#2 - Is one of the high pressure fuel lines running 1500-2000psi fuel pressure pulses to the injector. Fuel is pushed in one end by the injection pump #9 and comes out of the injector nozzle assy number 3 into the prechamber inside the head.

#3 - the injector nozzle holder assy. It breaks the fuel stream into an atomized pattern prepared for combustion in the prechamber.

#4 - This is the aneroid for the injection pump. It is an evacuated chamber attached to the governor mechanism for fuel control Its purpose is changing fuel mixture for altitude differences on non turbos and for boost enrichment on turbos.

#5 - The vacuum supply line from the vacuum pump to the vacuum assisted power brake booster.

#6 - The main fuel filter

#7 - The inline prefilter. It supplies fuel from the tank to the feed pump which it is attached to. It keeps the rocks out.

#8 - The return fuel line. This one looks like a piece of hose. The proper one is swollen in the middle to absorb pulses and dampen noise.

#9 - the injection pump

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

Dear stevebfl & WRM:

Thank you very much for your informative posts.

Special thanks to stevebfl for your very enlightening descriptions and explanations of these parts. BTW, I will have to replace all the 4 injector return lines (#1) and the diesel cigar hose (return fuel line #8) because they are not the proper hoses, right?

If someone has a 240D car, please take a digital picture of the same area (as in my attached image) and post it here. I would like to see the difference between my car and yours.

Thank you very much again.

Best regards.

Eric

"I will have to replace all the 4 injector return lines (#1) and the diesel cigar hose (return fuel line #8) because they are not the proper hoses, right?"

If it ain't broke don't fix it. I just pointed out points of interest about the items you listed. I have used bulk hose for the fuel return many times. I have never heard the noise that the hose is designed to reduce. Others have heard it though.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

Dear stevebfl:

Thank you so much for your precious help.

Best regards,

Eric

The PULSE KNOCK is REALLY noticeable COLD weather . . . kinda like an Idle Speed Control Cable without the bender clip on it . . .

Dear all:

I have another question: what is that black round piece that sits
between the numbers 7 (fuel prefilter) and 9 in the attached image?

Thank you.

Eric

That is the primer pump. If your car runs out of fuel, you'll unscrew it and pump it up and down to purge air from the fuel system.

I beleive the newer primer pumps are black at the top and do not require any unscrewing, just pushing down (it returns via a spring).

Haasman

__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

Correct. But what is shown in the picture is the older model with the plastic top and ribbed edges. Not really something that has to be done very often, unless you run the car dry.

Thanks haasman & speedy300Dturbo for your helpful replices.

speedy300Dturbo: You have a nice new house and great-looking cars :-)

Eric