Got the new filter today, and after working on my wave maker project I set about putting it in.

Installed into bracket.

Tucked behind spring tower, fuel line outlet attached first.

Then filter pulled forward towards front of van and inlet line attached. The the bracket moved into place and attached to tower with the screws. Do the rear screw first, then the front screw. Rear is towards rear of van, front is towards front of van.

Next is reinstalling carbon filter/canister bracket.

And finally the canister itself. I think I installed it higher on the bracket than before, but I don’t think I have crimped any of the lines at the top of the canister.

Overview shot of area.

In hindsight, I guess its not that bad of a job. But I can imagine it being hell with a van that has seen more salty winters. While I was in there, I removed an A/C line and the A/C drier that sat behind the charcoal canister, I’m stripping all the A/C stuff from the van.

The design team responsible for the fuel supply system in the Vanagon Syncro was led by a descendant of Leopold von Sacher-Masoch. No? Well how do you explain the location of the fuel filter then?

In camperizing the syncro I came upon the problem of screwing down the folding bed/rear bench brackets to the rear deck. I mentioned in a previous post how I drilled and tapped holes, but the rear deck is not thick enough to get more than one complete thread in it, so I went about making some little backing plates to build it up. On the passenger side it is no problem, the area is in the wheel well. But on the drivers side you have to reach up in wheel well, past the carbon filter and behind/above the gas tank. While doing that I decided to change the fuel filter which is located in that region.

Actually the fuel filter is attached to the inboard side of the spring tower. But you wouldn’t know it from this diagram (its #25, oh and the charcoal filter which is part of the emission control system is not shown here).

I did not take an “establishing shot” type pic, but here is a close up of the front side of the spring tower and the charcoal canister (I had removed the gear clamp that holds the canister to its bracket, which in turn is screwed to spring tower).

With the canister moved out the way a bit, you can see the filter, inlet end.

And if you peer around the rear of the spring tower, you can see the filter outlet end.

See that screw end sticking out? its one of two 10 mm hex headed screws that holds the filter bracket to the spring tower. I took both out, the “other one” near the front side of the tower is a bit awkward to get at, but I was lucky in that they were not rusted in. By the way, I did squirt all the fasteners with some rust busting stuff before starting. Hello bracket end!

I clamped the inlet and outlet fuel lines at this point too. I could get at the gear clamp at the outlet side so I removed that hose from the filter.

Then I struggled with pulling the filter forward, towards front of van, and down to get it out.

The above picture shows how it doesn’t come out. The charcoal canister, like an annoying relative, kept getting in the way, and the canister’s bracket to the right prevented the filter from coming out… oh wait, why not remove that dammed bracket, doh. Again, two 10 mm hex head screws, and the bracket is off and the filter and its bracket comes out.

I removed the filter from the bracket, sent the bracket and the charcoal canister bracket into a wash of naval jelly in preparation for painting. Here is the filter still in its bracket and beside it, the charcoal canister bracket.

Part number for the fuel filter is 450 905 030. Its used an a number of VW vehicles from the 80’s/90’s, should cost around 10 – 15 bucks.

Freed from its bracket, the filter underwent surgery.

The exposed paper filter elements were incised then retracted.

Yuck. I bet its the original filter.

The brackets are painted and now drying, tomorrow the new filter goes in. See that in Part II

Whereas I just poke around the fringes of syncro repair, Ed In Vancouver goes deep with rust repair and a Ford Zetec engine swap. His website is here.

I had time today to do a quick check of the alignment of my  prop shaft, or rather where the prop shaft goes, as I have it out right now…

I have to reiterate, this was a quick test, approximate measurements only. I attached my laser alignment jig to, in turn, the transmission output flange, then the front diff. input flange. Each time I measured down from the centre of the opposite flange to where the laser dot was. I also measured the distance between the centres of both flanges.

I did not measure any lateral alignment this go round.

What I found was the front diff was pointing down at a lesser angle then the rear transmission, 2.45 degrees vs 4.45 degrees. Ideally the angles should be equal and less than 4 degrees (but not zero degrees).

Here is a diagram of my results:

If you slept through trig, what you need to know is the TOA part of  SOHCAHTOA. TOA means tangent = opposite over adjacent. For example in diagram above, for transmission flange, the tangent of the angle is 100/1285 -> 4.45 degrees. Just do the 100/1285 bit on your calculator then hit the tan-1 button.

Here is a diagram of how U-joints can be oriented:

You can see how my syncro is in the “W” bend form, but the 2 angles are not equal. The angles must be equal, or damn close, to eliminate vibrations. This means I have to adjust the angle that the front diff. sits by shimming the front mount.

Look, its cold and windy today, hail at times. I don’t want to freeze in my cold workshop so I am sitting at the computer, ok?

Courtesy of Kafer and Co., Homburg/Einöd is this pdf file showing how to remove your syncro front differential when you want to swap in that new or rebuilt viscous coupling. PDF with pictures, about 800 kb.

front diff removal

This last summer I replaced the original u-joints in the syncro prop. shaft. The previous owner had removed the shaft for the summer, but told me there was some drive line vibrations. There are a lots of tales of woe and intrigue on the net about prop. shaft vibrations, causes and cures, so I decided to have a go at fixing mine. First thing was to replace u-joints. Stock VW joints are expensive, so I used the same replacement joints as Herman did on his syncro project (Precision brand, part #813). The bronze bushings that the yoke assembly and shaft fits into at the guibo end of the shaft seemed ok, the shaft fit in snugly. I just re-greased that, installed the new joints (blanking off the grease nipple fitting holes – I couldn’t get a nipple to fit in the tight spot, you’ll see what I mean if you ever do this job), and then painted the shaft. I re-installed the shaft and still had drive line vibrations at around 50-60 kph. I tried the trick of loosening the front differential mounting bolts and driving the van to let the drive line “find its sweet spot”, but that did not work. I removed the prop. shaft and re-examined it, and noticed some play in one of the joints. I removed that play by installing a thicker circlip (new joints came with two sets of circlips, differing in thickness).
That seemed to have removed the play. I double checked the fit of the yoke shaft into the bronze bushing, was ok.
The next step is to make sure transmission output flange and front differential input shaft are aligned to specifications. They are supposed to be aligned longitudinally, but each flange can be pointing down slightly, 4 degrees or so. I have made a laser alignment tool and I need to get under van and do the deed. One thing that has slowed me down is my suspicion that my viscous coupling is weak, but that’s a story for another blog entry.

Meanwhile have a look at the old u-joints. Notice the pounded marks on one of the bearing surfaces! (apologies for the blurry pic).