I agree with Crazy Nate here: purge the air through the hard metal injector lines. If I work on the fuel system, I purge it every time. IIRC, I use a 14mm crows foot wrench + 12" socket extension + socket wrench to loose the lines. I loosen the lines at the top of the intake.

So run the engine and then very slowly loose one of the injector nuts. As you loosen, it will weep fuel where the hole is. Loosen a little more and you will probably see bubbles. Loosen more and then your engine will shake and chatter. You want to purge the air at the point where you see bubbles.

This always works for me, so give it a go.

Also, search my posts as i had fuel delivery issues big time on my engine. I changed out the delivery valve seals, the fuel thermostat, changed out the rubber fuel lines up top, etc. Those three made the most change and *not* changing out the primary and secondary fuel filters.

Just crack it...........you're just trying to purge the hard line of air without the resistance of the injector.

i will try to do that today.

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hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

The problem still Arrives... If I leave the car sit for more then a day it's a right PITA to get running again...I've checked and Rechecked the main filter and it's always full of fuel.. it has to be either the Pre filter or the main...can the pre filter crack?

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hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

Do I remember reading about a seal at the fuel thermostat that can fail, causing these symptoms?

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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

Let's define "full of fuel".

My definition of "full of fuel" is that the fuel actually spills out the top of the filter when you release the bolt. There is not 1/16" of air space between the level of the fuel and the top of the filter housing.

If you drop the secondary and there is the slightest bit of air on the surface of the filter..........the filter is leaking fuel.

The reason that I suspect the secondary is the fact that the engine will immediately start if the primary is leaking..........fuel comes from the secondary. It might hesitate after 10 seconds or so.........but it will always start.

Your situation points to a leak high in the system that is very close to the IP...........air enters and fuel bleeds back toward the tank. The fact that the secondary was changed by the shop clearly points to "maintenance induced failure."

Did you notice if the aluminum washer is in place beneath the head of the bolt?

i did not see an aluminum Washer

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hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

The manual shows one o-ring and one aluminum washer.

But, I'm almost positive the '86 has two o-rings and no aluminum washer. But, I can check it in the morning.

Here's the schematic (for the 124.193). 607 and 610 are "seal rings", and if I remember correctly they're just the two o-rings on the bolt. I changed both out when I did my secondary filter a little while ago (I guess I would expect trouble if either is missing). I don't remember any aluminum washers

Attached Thumbnails

 

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1982 240D, sold 9/17/2008
1987 300D TurboW124.133 - 603.960, 722.317 - Smoke Silver Metallic / Medium Red (702/177), acquired 8/15/2009
262,715 and counting

Yep, that's the setup on the '86. There must have been a change somewhere along the way.........went to the double o-ring setup.

OK........another thought..........what's the chance that they used the wrong fuel filter.........??

For whatever it's worth, I have a 1987 300TD that became very difficult to keep runnning when the outside temperature dropped below 50 degrees F. I'd usually have to restart it 5-10 times before I could keep it running steady. I'd start it, it would run 5-10 seconds and then die out and I'd have to keep starting it again and again. The problem was a tiny leak at the fuel thermostat inlet fitting where it connects to the fuel thermostat.

Since I couldn't easily repair it, I bypassed the fuel thermostat and ran the fuel line directly to the fuel pump and that solved the starting problem. Yesterday the car started right up at 25 degrees F. I do not use the car in winter, so not sure if the fuel thermostat is needed in colder weather.

The leak was so small, there was no noticable fuel dripping below the engine but I saw a bit of fuel at the fuel thermostat connection when I was checking all the fuel fittings for air leaks.

You were given good advice regarding filling the fuel filter with diesel. That's a common problem.

Good luck

Rick

So, my filter went from sucking air to seeping fuel (can smell a strong diesel Smell after I turn the car off. It's a pain to start which tells me that it's sucking more and more air, and when it's running Diesel is seeping. I talked with the mechanic who said they did it right and something else is wrong. So, Does anyone have a picture or a breakdown of the Secondary filter and what goes betwixt the bolt, and filter. I was told there was supposed to be a aluminum washer in there but there's a rubberized one in there instead... Any ideas?

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hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

Try looking in these sites:
http://www.ps2cho.net/downloads/MB%20CD/W124/Main.html
Russian parts site in english
http://www.detali.ru/cat/oem_mb0.asp?TP=1

Part search narrowed some (It shows 2 seal rings on the Filter Bolt but does not tell what they are made of.)
http://www.detali.ru/cat/oem_mb1.asp?TP=1&F=124133&M=603%2E960&GA=722%2E317357&CT=M&Cat=503&SID=07

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84 300D, 82 Volvo 244Gl Diesel

the 2 last links wouldn't open for me... I know there's 2 o rings on the bolt, but is there any washer etc that goes between the filter and housing

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hum.....
1987 300TD 311,000M Stolen. Presumed destroyed