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roving sprinter
07-03-2011, 09:05 PM
I just changed the fuel filter for the very first time as I've just purchased my Sprinter over a month ago now, a 2003 T1N 118". From the service history I got with the van, I haven't seen a diesel fuel filter change for many many miles so I'm afraid it might not have been done for a few years. I had a very hard time removing the middle hose, the one with the plastic retaining "c" clip and oops... I cracked the black ring which the retaining clip snaps into. After filling the filter with diesel and re-installing it, I had to crank the van over quite a few times as expected, but then it finally started around the 4th try. I don't see any fuel seeping from the hose retaining clip which I cracked but do see some air bubbles going through the clear fuel line. My question is this; could the air bubbles be coming from that hose fitting even if I am not getting seepage, or is this simply air clearing itself from the new filter? I only ran it about 5 minutes and it idled just fine, the bubbles seemed to diminish but I do still see some tinny bubbles going through the line towards the injection pump. Is there enough pressure in the filter, if any, which cause the fuel line to pop out since the clip isn't really retaining anymore? Should I not worry about it if it runs fine and don't see any leaks? I just don't want to be driving and have that hose pop off the filter and suck up some major air, that would be a bad day indeed!

Aqua Puttana
07-04-2011, 02:16 PM
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Is there enough pressure in the filter, if any, which cause the fuel line to pop out since the clip isn't really retaining anymore? Should I not worry about it if it runs fine and don't see any leaks? I just don't want to be driving and have that hose pop off the filter and suck up some major air, that would be a bad day indeed!
As nobody else has stepped forward, I'll add what I can. I don't have an OM612 engine with your type fuel system so I can't go by experience. I'd think a bit of air bubbles after a filter change is not unusual. There is going to be air in the system from opening it up even if you filled the filter as much as possible. 5 minutes running might not be enough to move that entrained air out.

The fuel filter is under a negative pressure during operation because the mechanical low pressure pump mounted on the engine pulls fuel from the tank via the filter. That said, at shutdown the filter may see some positive pressure (not much) just from the static head of any fuel in the system although normally the fuel is locked in the closed system.

Plastic clips are made for ease of factory assembly and cost savings. If you can devise a method of retaining the parts in their proper place using cable ties, wire, or other parts you should not have any problems. I believe that there are threads here which show some retainer methods. They can be found using the search tool in the blue bar above. I may have even highlighted some of the threads in my Cheap Tricks or Stoopid Things threads. Sorry I can't offer more. vic

NelsonSprinter
07-04-2011, 08:31 PM
I just had a dealer replace that fuel line to fuel filter with clip which was broken for $65L + $26P OEM, part #6120700532. They said they were surprised it hadn't fallen off with just a zip tie strip holding it on.
The little bubbles, if they continue, may be due to a small amount of air being sucked in where the clip would have sealed it tighter. By the way, I now can see how clear the diesel is going out the filter where the old tube was stained brown.
For DIY maintenance, the least problems will occur if you research on the proper procedures here before you start.

Aqua Puttana
07-05-2011, 03:51 AM
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They said they were surprised it hadn't fallen off with just a zip tie strip holding it on.
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Just because the method isn't OEM doesn't mean it is destined for failure. Not all mechanics understand the principles of o-ring seals and alternate retainers. The easy thing for them to do is just criticize the other guy's method. Even if they do understand they are often required to stick with OEM parts. If the jury rigged method held the parts aligned properly in place, the o-ring seal should have done its job. Maybe the o-ring seal itself was bad? That would have been replaced with the new parts so the problem went away even though the retaining method could have been fine. That said, I never saw the alternate method that was used to secure the parts in place on your Sprinter.


For DIY maintenance, the least problems will occur if you research on the proper procedures here before you start.
Good point. There's a bunch of good information here at Sprinter-source, Yahoo Sprintervan, and other forums. Have fun. vic

roving sprinter
07-05-2011, 03:47 PM
Thank you for your valued input on my filter change. I put some heavy duty plastic ties to hold the fuel hose in place although it was on very tight without the ties, perhaps the hose fitting is still functioning even with the break in the retaining ring. I drove the van yesterday and see no issues nor leaks and since my fuel line is still very clear, I can see the bubbles have diminished. Anyway thanks for helping out a Sprinter newbie, love the van!

surlyoldbill
07-05-2011, 05:25 PM
I broke the plastic retaining clip the first time I changed fuel filter, too.

mawsea
07-06-2011, 12:40 AM
I just went thru the same thing this weekend! Besides breaking the retainer clip, it turns out the O ring had a nick that was lettin air in. After replacing that I was still getting air in the lines, turns out the O'ring on the water bleed valve on the bottom of the filter was also bad. Problem solved!

Dent Head
07-06-2011, 03:38 PM
After changing the FF, attempt start only once. If no go , wait fifteen minutes for pressure to fill empty space with fuel. Multiple immediate attempts to start are a waste. Avid DIYer.:professor:

hkpierce
07-06-2011, 08:06 PM
After changing the FF, attempt start only once. If no go , wait fifteen minutes for pressure to fill empty space with fuel. Multiple immediate attempts to start are a waste. Avid DIYer.:professor:

?????? Pressure from where? For OM612s, sitting for 15 minutes is not going to result in any change, and for OM647s the key must be on for the electric fuel pump to operate (and even then the air has to go someplace).

Among several fuel filter threads for 612s:
http://www.sprinter-source.com/forum/showthread.php?t=169&highlight=fuel+filter


http://www.sprinter-source.com/forum/showthread.php?t=170&highlight=reprime