fuel leak, PLEASE help - PeachParts Mercedes-Benz Forum

Biglex · #1 03-09-2007, 05:41 PM

If someone can tell me what this part is, I would REALLY appreciate it. There is a fuel leak where the fuel line comes out of this and leads to the primary fuel filter. I have pretty well ruined the street with this leak so I need to get it fixed.

It is on my 92 300D.

All kinda thanks.

jaoneill · #2 03-09-2007, 06:08 PM

Can't tell you the correct name for it, but I can tell you that it is a very simple , 20 minute fix to replace the o-ring that seals around the hose barb where it enters the housing. I had the same issue a few months ago.

Jim

Biglex · #3 03-09-2007, 07:03 PM

So did you have to take the whole unit off and unhook all of the fuel lines, or just the one on the end?

vstech · #4 03-09-2007, 10:01 PM

I've never had a problem there, but it sounds simple to fix. I would spray some degreaser on the thing and rinse it off real good, and see how it comes apart.
are you sure it's leaking from the part, not the short hose?
John

cgunderm · #5 03-09-2007, 10:46 PM

Quote:

Originally Posted by jaoneill

Can't tell you the correct name for it, but I can tell you that it is a very simple , 20 minute fix to replace the o-ring that seals around the hose barb where it enters the housing. I had the same issue a few months ago.

Jim

It looks like it's the thermostat for the fuel heater that these models have. You might first want to check, as someone else suggested, if it isn't the fuel line between the pre-filter and this thermostat that's leaking. How bad a leak is it? (you say you ruined the road?? is it so massive?)

Biodiesel300TD · #6 03-09-2007, 11:18 PM

That's your lift pump isn't it? I would wipe it down real well and see what is really leaking. The hose or the connection. Looks like you can take apart the connection and replace an o-ring or crush washer. Or the hose if it's leaking.

Biglex · #7 03-10-2007, 12:35 AM

It is leaking bad to the point that when I park and come back in the morning, there is a puddle of standing fuel on the ground. It isnt the fuel line leaking, I have degreased it and dried it off. I actually saw the fuel coming out of the front side of it today. Getting o rings tomorrow.

jaoneill · #8 03-10-2007, 11:12 AM

Quote:

Originally Posted by Biglex

So did you have to take the whole unit off and unhook all of the fuel lines, or just the one on the end?

As someone commented it is the T-stat/distribution valve for the fuel heater. I took the whole unit off (2 bolts plus fuel lines - 5 minutes) for ease of access (it is under intake manifold and difficult to get at on my 190D). Once on the bench it took longer to clean it up than it did to change the o-ring.

Jim

Biglex · #9 03-19-2007, 07:18 PM

Well, I got it changed. It wasnt easy to get to all the hoses, but its done. The o-ring didnt seem to be in any kinda bad shape, just seemed to be really flat along the outside. I put a nice big fat one in so hopefully the problem is solved. Thanks guys.

benzforlife · #10 03-19-2007, 07:20 PM

just out of curiosity is that bio diesel, it looks like a rich golden brown color. pump fuel is usually greenish blue around here?

pawoSD · #11 03-19-2007, 07:23 PM

Quote:

Originally Posted by benzforlife

just out of curiosity is that bio diesel, it looks like a rich golden brown color. pump fuel is usually greenish blue around here?

I was also wondering that....the fuel in the prefilter looks like fry oil to me...

Biglex · #12 03-20-2007, 03:16 AM

yep, im a wvo user. This was the first problem I have had with it, but I am sure I will come across more. I am just wondering what I can do now to dye it the color of regular diesel.