1984 300D total fuel capacity - PeachParts Mercedes-Benz Forum

WMO Madness · #1 10-17-2012, 08:01 AM

I had some business in PA yesterday, I thought it would be good to test my 1984 300D on long range driving. 289 mile was showing on the odo and the gas gauge was showing just over the half tank mark. So I thought to myself I should make it home on that. About five miles later I felt a major lost of power, and I couldn't not accel. I fulled over and parked, the car died and wouldn't not start.

Everything looked normal under the hood, so I decided to pump the prime bottom. It was weak, since I am running 100% on WMO, I had 10 gal with me. I poured in five gal and pump the prime bottom again. It started to pump in fuel. The car started after first attempt but died, pump the bottom again.. This time it started and with me pumping the gas it kept running.

I drove to the fisrt rest area and poured in the second 5 gal I had with me, then topped it off. To my surprise it only took 1.5 gal, I kept filling until I saw fuel.

The two five gal gas can I had might had more than 5 gal, maybe total for both can was 11-12 gal plus the 1.5 I pumped in. That would make the tank total capacity of 12-13 gal. Is this correct? Oh yeah, with this adventure I can honestly say the gas gauge is not working properly.

Skippy · #2 10-17-2012, 08:07 AM

If your fuel supply and return hoses are reversed, that would only get you access to about half of the tank's capacity. The thing should hold something over 20 gallons including reserve. I just filled my '83 up tonight and it took 17.8 gallons from having the reserve light on for a few miles.

I wouldn't run straight WMO in any diesel engine, but that's a topic for a different thread.

WMO Madness · #3 10-17-2012, 08:13 AM

Quote:

Originally Posted by Skippy

If your fuel supply and return hoses are reversed, that would only get you access to about half of the tank's capacity. The thing should hold something over 20 gallons including reserve. I just filled my '83 up tonight and it took 17.8 gallons from having the reserve light on for a few miles.

I wouldn't run straight WMO in any diesel engine, but that's a topic for a different thread.

I can I determined if the fuel line are reverese? Do you have photo which line should where? Thank you.

Skippy · #4 10-17-2012, 08:40 AM

I don't have pics, and it's dark out right now. It's fairly common to reverse the lines under the hood on the left side of the engine as a test to see if the fuel strainer in the tank is plugged. It's not unlikely that a previous owner switched the lines for this purpose at some point and forgot to put them back.

Edit: I'll bet someone on this forum will come up with pics within the next 24 hours.

vstech · #5 10-17-2012, 08:49 AM

top steel line from tank should be the return.

vstech · #6 10-17-2012, 08:50 AM

you could also have a collapsed tank, pull the carpet from the trunk liner, then pull the bulkhead, then look at the tank, if it's collapsed, you'll see it.

WMO Madness · #7 10-17-2012, 09:48 AM

Quote:

Originally Posted by vstech

you could also have a collapsed tank, pull the carpet from the trunk liner, then pull the bulkhead, then look at the tank, if it's collapsed, you'll see it.

I pulled the bulkhead out and verify the tank, it is not callapsed. I also verified the return liine, it is hooked to the top steel tube. I went ahead and looked at the 300SD, my is hooker the same.

I know this is probably belong to another discussion, but when I was pumping the prime bottom after it got hard and pumped it one more time. some fuel leaked out along the shaft of the plastice tube. Is this normal? Is there somekind of pump (elecetric or mechanical) in the tank or outside the tank that prevent fuel from making it to the engine bay? Thank you for your quick reponse.

junqueyardjim · #8 10-17-2012, 09:48 AM

Darn, it about makes me barf to just think about poring 100% used motor oil in the fuel tank. But it will probably run on it for a while. I have about 15 gallons to give you if you ever come by Indy. I think it is a good fuel for some types of shop heating, not for a good diesel. But it is your vehicle.

Simpler=Better · #9 10-17-2012, 04:36 PM

Quote:

Originally Posted by WMO Madness

I pulled the bulkhead out and verify the tank, it is not callapsed. I also verified the return liine, it is hooked to the top steel tube. I went ahead and looked at the 300SD, my is hooker the same.

I know this is probably belong to another discussion, but when I was pumping the prime bottom after it got hard and pumped it one more time. some fuel leaked out along the shaft of the plastice tube. Is this normal? Is there somekind of pump (elecetric or mechanical) in the tank or outside the tank that prevent fuel from making it to the engine bay? Thank you for your quick reponse.

You want the updated pump:

They're like $20 here on the forums.

WMO Madness · #10 10-17-2012, 08:50 PM

Quote:

Originally Posted by Simpler=Better

You want the updated pump:

They're like $20 here on the forums.

Thank you, the 1985 300SD I got from a buddy has one. I'll remove it and replace mine.

vstech · #11 10-17-2012, 09:18 PM

if you begin running out of fuel at the 1/2 to 1/4 mark, you could easily have a plugged up tank strainer. pull yours and verify.

WMO Madness · #12 10-17-2012, 09:34 PM

Quote:

Originally Posted by vstech

if you begin running out of fuel at the 1/2 to 1/4 mark, you could easily have a plugged up tank strainer. pull yours and verify.

Where is that located?

Merica · #13 10-17-2012, 09:54 PM

The strainer is located on the underside of the fuel tank. You'll see where the metal fuel lines end and a small section of rubber hose joins the strainer to the metal line. It is threaded and requires very large socket, although I think channel locks might work to get it off.

charmalu · #14 10-17-2012, 11:02 PM

1 13/16" 46mm socket is what you need. I have removed these and using a pair of Channel lockk pliers looks like it would be difficult to get it up in the space.

This thread has all your answers.

46 MM socket for fuel tank strainer removal

If your strainer is partically plugged. when you remove it, you will get a bath of fuel of whatever type you are using.

I removed one on a 240D after draining the tank with the supply hose. had some large pans under to catch what ever came out, and still got a bath as it came gushing out quickly. be a good idea to raise up the right side of the car to get the fuel to flow to the other side before removing the strainer.

Charlie

charmalu · #15 10-17-2012, 11:12 PM

I have one like the above picture. note how the edge bevels in? mine is like that and doesn`t grab the strainer very well. I need to have a guy with a lathe to cut it in 1/2, then slope the outside edge a bit.

Most of thse sockets are 3/4 drive, and by the time it is reduced to say 3/8, then it crowds the small space you have to turn the socket. was thinking of having 3/8 adaptor welded in.

Charlie