I have a E350 box van behind the fuel filter is a black thing that the fuel line connect to. Can anyone tell me what this is and if it contains a filter.

 

Do you have a single aft tank?? which is common on the cubers.

The only thing I can think of is a selector switch, for duel tanks, does it look kind of like this -

http://info.rockauto.com/Airtex/Detail.html?8F1312.jpg

If it is a selector switch, there will not be a filter in it.

There is the vapor trap, which is a large back box, but thats mounted on the right side, outside the frame, just behind the pass step.

 

I've had people tell me there is a filter in it, but here's what I had. 1988 E-350 and that thing started leaking. Went to a Ford dealer to get an oring for it. However they only sold the whole thing and the parts guy said it did not have a filter and to not open it up. However I could not get the 2 bolts out as the nuts, which were not accessible, were spinning free. So I did take the bottom off, it did unscrew, there was an oring, there was NOT a filter. From what I have read here, 86 was the only year there was a filter in there.

 

Here it is:

https://www.ford-trucks.com/forums/7...ve-source.html

However I do not think it's a fuel selector as it has no wires going to it from what I remember.

I believe it is a vapor canister purge valve and is demand operated. I am assuming that after reading about 20 pages of text online, at RockAuto.com, and some pages here.

 

Ya know, I got thinking today, and I have a '91 parked, so I climbed under there and saw what your talking about.

I remember that from long ago, but I can't think what it is for off hand. I know the tank lines go into it, and back out, it could have something to do with vapor.

2000Ford, if your just looking for an O-ring, I'm sure you can match up one at like Advance auto parts.

 

It was a long time ago, on my RV, traveling through Florida. I stopped at the dealer because I assumed (wrongly) that they could work on my RV as the main problem was a dragging caliper. After finding out that they wouldn't work on it right away, I talked to their Ford parts guy who said not to unscrew the cap, and I think he really didn't know as he showed me his microfiche of that part and it wasn't broke down to show any O-ring, so I figured it was just broken so I bought the whole deal. It wasn't until I stopped in Merritt Island Florida that I took some big slip ring pliers and actually found that it unscrewed. I expected a filter but it was just a cup of gas. So I took the new one apart and put the new O-ring and cap on the old mount and all was well.

 

From seeing close up, what it looked like, I figured it was some kind of buffer between the fuel pump in the tank and the one up by the engine. I could see no other reason to have a plastic cup full of gas on the fuel rail.

It was different than my 89 vans as they had 6 connections to it for the dual tanks. The 88 RV had a single 35 gallon tank, which was really dumb since it only got 5.5 mpg and the generator would only pull the tank down to 33% so I had to stop every 100-120 miles if I wanted overhead AC.

 

Thanks it is a single rear tank. The unit has tank line from tank to fuel pump then return line from engine to tank. What I was wondering is if the cap that threads off can get full of dirt as my filter was plug tight. and this unit is before the filter.

 

If it did get dirt in it, it would be sucked right out onto the engine. Unless it stuck to the plastic, it would not stay in that cap.

You can check but you may ruin the O-ring. I was able to get mine off with a large set of channel locks and it was really tight.