Fuel starvation. When removing hose from primary (see through plastic) filter, fuel runs out so the feed hose from the tank does not appear obstructed. Tank screen is clean.

Car runs fine when run off of a 1 gallon jug under the hood bypassing the car's hoses, lines and tank.

Any suggestions?

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__________________
'83 SD, 2x '85 SD
You are entitled to your own opinions, you are not entitled to your own facts.

Bad lift pump?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

If this happened after filling the fuel tank, suspect BAD fuel.

Warning ALL Diesel Owners
http://www.peachparts.com/shopforum/diesel-discussion/309367-warning-all-diesel-owners.html#post2841158

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Building Vacuum in the fuel tank will starve the injection pump...

Imploded fuel tank - so sad!
http://www.peachparts.com/shopforum/diesel-discussion/314457-imploded-fuel-tank-so-sad.html

What happens when a tank vent gets clogged.
What happens when a tank vent gets clogged. - PeachParts Mercedes ShopForum

Why do I have vacuum in my diesel tank.....................?
Why do I have vacuum in my diesel tank.....................? - PeachParts Mercedes ShopForum

What is this valve and why is it dripping diesel?
http://www.peachparts.com/shopforum/diesel-discussion/317902-what-valve-why-dripping-diesel.html

Fuel tank vent pictures + location
http://www.peachparts.com/shopforum/2878700-post39.html

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This is doubtful, but still possible.

Fuel injection pump starvation with a good lift pump
Fuel injection pump starvation with a good lift pump - PeachParts Mercedes ShopForum

Fuel pressure relief valve adjustment
Fuel pressure relief valve adjustment - PeachParts Mercedes ShopForum

lift pump test
1979 300td -- Can anybody walk me through a lift pump test? - PeachParts Mercedes ShopForum

fuel pressure
fuel pressure - PeachParts Mercedes ShopForum

Here's my payback! Diesel Primer Pump Replacement
Here's my payback! Diesel Primer Pump Replacement - PeachParts Mercedes ShopForum

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__________________
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1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

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More info would help.
When is the last time you changed the primary (spin on, not clear plastic) filter? Is the return hose to the tank clear?
It's just the beginning

__________________
'70 F100 shortbed
'82 Diesel Westy
'83 Euro 300TD
Curtlo Viper
Yeti ARC
Surly long haul trucker

"Torment" I think you found a fitting name for My Car!

__________________
84 300D, 82 Volvo 244Gl Diesel

Not only "fine", I can chirp the tires and it hums along at 80(+) until the jug runs dry.
Please correct me but wouldn't the above eliminate:

Fuel is known good fuel. I've been grappling with this issue for months, all the while running the car off of the gallon jug.

Also tried driving with fuel tank cap removed. I had replaced the hoses (one side shown rotted through) on either side of the Fuel Tank Vent Valve (part#1234700393) . I thought that might have cured it and tested driving with the tank again (only filling it with a gallon or 2 at a time). It seemed to work. Then put in 5 gallons. Drove fine. Then it started acting up again.

Looks like draining the tank (again) and sending compressed air through all the lines might be the next move.

"Daily drivers, except when they're not" or "own at least two so you can at least drive one" - ought to be our community's motto.


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Attached Thumbnails

 

__________________
'83 SD, 2x '85 SD
You are entitled to your own opinions, you are not entitled to your own facts.

In the interest of reducing confusion, the spin-on filter is the secondary filter, not the primary.

Fuel runs downhill easier than it runs uphill. I would further evaluate the fuel pump. When mine was going south, the car would feel like it gained 20 hp after filling a near-empty tank. ('83 300D.)

I installed a $4 fuel pump repair kit and got amazing results.

If the prefilter is clear enough. Have a look for a stream of bubbles going through it. With the proper fuel lines hooked up of course .The larger bubble observed is normal and should be pretty static. You could have a pinhole developed under a line retaining clip for example. you also do not want to see fuel surging back and forth in that prefilter.

Since at one time we dealt with a lot of gas tank feed issues. It was occassionally a situation of closing off the feed line in the engine compartment and pulling a vacuum on the tank end of the line. A normal system will hold the vaccum.

To verify the issue in your case although I am not particularrily happy about doing it. Reverse the feed and return lines in the engine compartment. If things normalise you know pretty well exactly where the issue is. You should have a half tank of fuel or more to do that test.

[QUOTE="Daily drivers, except when they're not" or "own at least two so you can at least drive one" - ought to be our community's motto. .[/QUOTE]

My sentiments exactly!!

__________________
Mine: 1987 MB 420 SEL - 62K (Dec 2019)
Mine:1991 MB 350SDL - 244K (Aug 2011)- Totalled 9/14/2016
Mine:1981 MB 300SD - 326K mi (July 1997)-sold
Wife's: 2008 MB C300 Sport - 92K mi (April 2009)

I know the spin on is second in line but I can't help myself in calling it the primary as it does the hard work

__________________
'70 F100 shortbed
'82 Diesel Westy
'83 Euro 300TD
Curtlo Viper
Yeti ARC
Surly long haul trucker

Did you pull the fuel tank strainer? Sounds like it might be partially plugged? Try swapping the feed and return lines near the primary filter (small plastic one). You stated you added five gallons and it was fine. How much of that was used before the problems returned?

Sounds like the two lines. Fuel supply and return may already be reversed. You have to have a decent amount of fuel in the tank for the return line to function as the main fuel feed. The last post on this thread plus re reading your post stirred this thought up..