Hello all.

I have an 82 300d with a diesel leak near the drivers side rear wheel well. I am attaching a pic because I am not sure what the bell looking part is. This is the area where the leak is at but I cant tell just where. Any help is appreciated. Would it be easier to run a new rubber line from the tank to beyond the leak area? Thanks

Attached Thumbnails

 

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96 F350 CC, LB, 4x4. 290,000 with around 90,000 on wvo.

82 Mercedes 300d. New to me. 211,000 soon to be on wvo.

Fuel tank vent valve.


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That is the fuel tank vent. That is not leaking fuel as that allows air to replace the fuel that has been consumed while running and should not have any fuel in it. What you do have is a corroded fuel supply or return line. IIRC there are three lines running along the floor board. One of the lines is the supply from tank to engine, one is the return from engine to tank, and one is a brake line. that is an easy fix but mine did not look as neat as factory when done. If anyone knows of a great tubing bending tool or method please start a new thread or PM me as I did mine in two pieces ( rubber hose at center in feed and return line)

Thanks. I believe it is probably the feed line. Would it be easier to replace from the tank to that tricky spot or just splice some line in? I don't think its under much pressure, wouldn't some rubber fuel line work just fine? I have spliced it on my powerstroke pushing 80psi through it with no issues at 130,000 miles.

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96 F350 CC, LB, 4x4. 290,000 with around 90,000 on wvo.

82 Mercedes 300d. New to me. 211,000 soon to be on wvo.

I replaced mine from the tank to about under the rear door pillar with pipe and a rubber/viton hose about two inch section connecting old to new. You must run down some lime stone roads as that is what I suspect did mine in along with some salted roads.

Thanks again. Where will I find the fuel tank ports? Is this something that can be done with a jack in a sandy driveway? Does it require dropping the tank? I also have a trans and oil leak. What I would give for a garage and and a lift. What I got is a sandy driveway and a jack.

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96 F350 CC, LB, 4x4. 290,000 with around 90,000 on wvo.

82 Mercedes 300d. New to me. 211,000 soon to be on wvo.

I backed mine up on ramps (should have put it on stands) but all acme out well in the end. The hardest part was fishing the new hard lines over the rear suspension keeping it near the underbody. The clamps/braces that hold the lines to the underbody were a testimony to Mercedes engineering as easy to remove and replace. The ports are at the tank drain first or run it down to near empty.

I cut out the rusted line and used rubber fuel hose and circle clamps to fix it. You want to siphon empty your tank or you will have quite a mess on your hands. You can search my name for detailed pics on the fix.

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85 300CD Signal Red/Tan sold
83 300D Manganese Brown 109K
97 E420 Midnight Blue 197K sold
98 BMW 328i Vert White 100K, sold
95 BMW 525i White 125K, sold
93 BMW 525iT Red 193K, sold
95 E320 Green Wagon 125K, sold
94 E320 White 127K, sold
85 300SD 156K Grey (Annie), sold
84 300D Lapis Blue 170K (Judy), sold
99 ML 320 Black (lease), 1998 C230 White (lease)
00 Honda S2000 Red (lease)
86 Mercedes 300E (sold)
84 Porsche 911 Red (sold), 1965 Porsche 911 White (sold)

I fixed mine the same way - needed about a foot or so of rubber hose. Had to drop the trailing arm to make sure I had good solid pipe. Been good to go for at least five years.

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Len
'59 220S Cabriolet-SOLD and living happily in Malta
'83 240D 351,500 miles original owner-SOLD
'88 560SL 41,000 miles - totaled and parted out
https://sites.google.com/site/mercedesstuff/home
'99 E300 turbo 227,500 miles
'03 SLK320 40,000 miles - gave to my daughter
'14 Smart electric coupe 28,500 miles
'14 Smart electric cabriolet 28,500 miles
'15 Smart electric coupe 28,000 miles