Laparoscopic fuel vent hose repair without dropping tank

[PeteB]

Found this picture on here, ours has a clamp where I drew the red arrow, so
I'm going to assume that it is one or the other and ours uses the short one:
I bounced the back end of the car up and down and could not get any sign
of gas on the top, or any drips. When I filled it, it dripped a lot, and I only
drove it 2 miles home. It is slightly sloped with the front higher, which from
the picture might push the gas to the back away from the vent. I'll try to
level it or add a bit more fuel.

VENT-HOSE.JPG (92.83 KiB) Viewed 2529 times

[erikv11]

As far as finding the source of the leak: It's really not very hard to drop the tank, when empty it is surprisingly light.

Frankly now whenever I have a leaky fuel P80 tank I first shore up the fuel pump (epoxy the top at the wires if cracked, replace the rubber gasket with genuine Volvo part), and then if there is still a leak just drop the tank. Then you can eyeball exactly what the problem is, and fix it easily. Replace two hoses if you need to. Drive it down below 1/4 tank, siphon out the rest of the gas, and go to work. You just did rear brake lines under there, by comparison this will be a walk in the park.

[PeteB]

It has a very full tank right now, I could run it down but I'm just going to try to
do it from the top for now. Don't want to deal with the rusty bolts.
I've read that some have trouble getting the tank back up.

[PeteB]

I was just at FCP and to answer my own question, we entered our VIN into the
system, looked at the fuel system diagram, and sure enough there were two hoses,
the long one as pictured above and a short one that matches the red arrow in the
picture. Had to order the hose and it was not cheap at about $29.
The different parts were based on some number, not sure what it was so we went
by the pictures.

[PeteB]

Hose #3501350 is not correct, as kahl posted earlier in the thread, it is about 1/8" ID
and 2-3 inches long. I could not tell the scale size in the picture and thought it was the
short version.
Kahl wrote: "3501350 is fuel tank vent hose at roll over valve."

[PeteB]

I've not done anything more to the car, and walked past it today smelling gas,
looked in and it was completely wet on the top of the fuel pump. I do remember
having trouble tightening the ring and was able to turn it 1/4 turn by hand so I'll
get the tool out tomorrow and see if tightening it fixes the problem.

I'm rereading erikv11's advice and will probably do the epoxy fix and gasket also.

[PeteB]

Repair around fuel pump wires is covered in this thread:
viewtopic.php?t=24518

This picture from that thread shows the short version of the vent hose that we have:

SHORT-TANK-VENT-HOSE.JPG (151.51 KiB) Viewed 1997 times

[PeteB]

The material around the fuel pump wires was flaking and coming out.
I was going to use some JB Weld that I had, then read online that while okay
for gasoline, it softens with ethanol blended fuels.
I bought QuikSteel plastic tank patch from Autozone for about $13 and figured
pay a bit more and do it once. Going to let it dry, tighten the ring with a wrench
and test it tomorrow. We might not need the vent hose.

[erikv11]

An epoxy like that is a great way to go with that issue. Fast, easy, permanent. On mine, the wire surround was bad so I'm glad I fixed it but in the end problem ended up being the fuel pump gasket. Volvo only on that one.

[rspi]