Hello to the forum's experts.
Well I read a lot on this forum for the last few months and learned so much.

I'm working on my new 300TD (first Diesel ever) to bring it to perfect condition.
During this process I do take lots of pictures as I have the intention to post a picture documented web site how to fix things.

When I moved the spare tire I found a small plastic tank (almost shaped like a kidney) that has three fuel hoses connected to it (the hoses are not the same size).
What I saw which I didn’t like was that only 2 hoses where connected and the third was plugged and on top of it all the 3 were leaking diesel.
When I pulled the tank out I discovered:
1) It was cracked on top and bottom.
2) That there is a hole where the (I assume) the third hose was connected.

As I explore my options:
1) Fix the cracked tank
2) Buy used one
3) Build a new one from stainless steel

I don't like #1 as it will be tricky to fix the broken hose part.
#2 where is a good place to find one (I live in San Francisco area, Marin county) I searched on line different options and none offered the fuel expansion tank option
#3. I would like to know how is the internal of the tank is.
I.e. are there different heights in the tank for the tube that connect to the hoses?

If there is a kind sole who knows what is the diameter of the hoses it will be great. I bought a part online and the ID it to big to fit anywhere.

Thanks in advance.

PS. Attached are the pictures of the seeping hoses and the tank.

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The part number is there in your picture.
Call Phil, he can get it.

Questions about Parts?
Call Phil for help at
1-888-333-4642
Mon-Fri 10:30a-8:00p ET
(NOT for technical support)

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1985 300SD
1983 300D
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did mercedes do this in other cars? this aux tank? i have a 300SD, im just curious..

I had a cracked expansion tank in my '85 300TD. I tried using heat from a soldering iron to melt the plastic, then I tried using silicone rubber to no avail.
I continued to have diesel fuel smell in the car from the small amount that leaked from this tank. I checked out the tank in my '79 TD and discovered it was made of metal!
I lived with that for many months, and when I filled up I would only fill to 75% full or less to prevent some fuel from going into the expansion tank (that is what it's for, fuel expands when hot! Gassers use this too, its necessary in all "modern" vehicles.)
I finally spoke with a fellow that was parting out an early wagon and he sold me the metal exp. tank which fit perfectly. Why do you think MB started using plastic in a critical area like this?

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'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!

Thanks for the lead. I'll call him tomorrow morning. Just in case it is expensive part. Do you know by any chance how this tank works ?
There are 3 lines to it. Mine had two connected and the bottom one plugged as the conncetion was broken. Again I appreciate any advice

Yossi

Trying to save money I will first try to fix the cracked tank with JB weld or something like that. Anyone care to comment if it will work.
If it will not work what do you think about this tank ?

Please let me know what do you think
Thanks,
Yossi

I make small tanks; but only for myself, liability is bad news.

$100.00 USD is not bad.

Well 3$ is better when it comes out of my pocket :-). I sealed it with JB weld. Attached a hose connector to the missing port. allowed it to dry for 24 hours, replaced the oozing hoses and for time being it works well. I wil monitor it closely in the next few months.

Yossi

JB weld is not going to work for that sort of plastic.....have you talked to a large well respected body repair shop....many of them are familiar with plastic welding and repair.....its best to do it right. Cracked bumpers can be and are repaired every day.....and thats likely a simular if not identical material.

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
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Section 609 MVAC Certified
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"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

I love JB Weld

There is about a pound of it thought my car.

I am always amassed by the stuff.

Like the time I used it to patch a hole in a radiator, and to fill and retap stripped out aluminum bolt holes.

Once I win the lottery, I will buy the company and spend the rest of my life making sculptures out of JB-Weld.

Duct Tape.

I took my out a cleaned it really well with alcohol, it had a couple of cracks in the center and on the sides, that created that diesel smell in the back.

So I duct taped it. And it's been about a year with no smell...Not perfect but better than speeding a hundred bucks...

Oh and don't even bother going to a junkyard to find one of these things...I check atleast three car and all have been cracked.

Jason

Well JB weld is the best I could figure on my own :-). I intend to check it out once a week or so for the next few months. If it won't hold I intend to build something from Stainless Steel. I'm in the process of building a tank for the WVO in the trunk area of the car. So welding is available at this time.

Yossi

Why didn't I think of it? LOL
If I had to guess if it will hold I would have guessed NO as the diesel will desolve the glue. I'm happy to learn at least one new thing a day :-)

the problem is not the diesel desolving the glue...its the mechanical connection between the glue and the tank....you should enquire with a body shop about if they can repair it...those guys have stuff joe average can't buy....and if they are able it would be permanent and cheap

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
---------------------
"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

I'll file this information in case the JB weld will fail. Just FYI I tested the tank with my bike pump it held 30 PSI without any problem.
I don't think that the pressure in the tank will be higher. Only time will tell though.