2010 Jetta fuel filter bleed screw

Can someone with a Bentley manual tell me what the procedure is for using the bleed screw on top of the fuel filter canister. Or, if nothing is mentioned on the use of this screw, what is the proper procedure for replacing the fuel filter and checking for water?

When I asked if any water was found, I got quite a run around from a dealer before they finally said, "there was some, but it isn't a problem". The bleed screw has never been touched, so I'm not sure how one is expected to check for water.

The "official" procedure is to remove the screw and use a syringe or suction device and draw out a few ounces of fuel/water (the manual says to remove about 100ml (3.4 oz) of fuel). Most of the people who have reported anything have stated that they found no water. Most newer TDIs do not even have this screw. New filters come with a new crush washer to re-seal this screw after removing. Probably the best way to do this would be to use a large syringe with about a 10" plastic tube on it. Stick the tube down the hole until it hits bottom and suck out whatever is in the bottom of the filter housing. Then let it sit for a while and see if there is any oil/water separation. I live in the middle of a desert where water (in any form) is rare, so I have never bothered to even remove this screw. IMHO, the biggest advantage to removing this screw and sucking out some fuel is that the filter housing is not so full and you are less likely to slop fuel out of the filter housing.

Have Fun!

Don

You're better off removing the filter base and dumping the contents into a jar to see what's going on in there rather than messing with that screw.

El Dobro said:

You're better off removing the filter base and dumping the contents into a jar to see what's going on in there rather than messing with that screw.

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Why's that? Using the screw seems logical. Why remove the whole thing? Why not either use the screw or sipphon out the fuel with the top off? If the procedurr is to use the screw..... Otherwise, why on Earth is there a screw there in the first place?

pleopard said:

Why's that? Using the screw seems logical. Why remove the whole thing? Why not either use the screw or sipphon out the fuel with the top off? If the procedurr is to use the screw..... Otherwise, why on Earth is there a screw there in the first place?

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When that fuel filter assy first came out, they used a different filter element inside that separated the water. Not too soon after that the element and the lid were changed and the screw was eliminated. This was all when they first came out with the MkV body with the PD engine. When VW brought the CR engines out, they brought back the original filter assy with the screw, but they still used the second design element that doesn't separate water from the fuel.

If you remove the body, which only takes a few minutes, you can pour out stuff that settled to the bottom that may or may not come out by siphoning. There's a thread around here somewhere that covered the different fuel filter assemblies that VW used on the MkV bodies.

Changing the filter on schedule is really all that is needed. Water in there is a rare event now days. The older A5's had bayonet mounts on the canister and it could easily be slid out when changing the filter. The contents could be dumped into a container and settled/examined. If nothing found added back to the tank.

So, if I'm understanding correctly, there's no point to even using the screw as no water separation even occurs with the new filter? Color me confused.

pleopard said:

So, if I'm understanding correctly, there's no point to even using the screw as no water separation even occurs with the new filter? Color me confused.

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Yep, the filter assy. with the screw was dropped in late 2005/early 2006. They brought it back in 2009, but there was no need to use it. I believe that's why there's a drop of sealer in the head of the screw.