1998 V aWd fuel leak above drivers tank

h20ham · Post by **h20ham** » 10 Oct 2018, 19:39

Great day
Out 98 has some fuel dripping while running, coming from above the drivers side fuel tank. Not much fuel, but...its fuel.
My guess is, that because the pump and sender are on opposite side (passenger). And as the crossover and return line is below where the fuel is coming from. Is, fuel is squirting up from the either the return line, or crossover. Finding a Chanel to leak down from the top, along the side.

Any and all comments appreciated

Hope y’all are having fun
James

Post by **scot850** » 10 Oct 2018, 20:13

I'd start praying! There is no real way of checking the tank short of dropping the rear sub-frame and fuel tank to see where the leak is. There are several pipes up there that have rubber connectors and the metal sections that connect to the fuel pump (RHS front of tank) and the ejector 'pump' on the LHS front of the tank. The ejector is not an actual pump but a king of fuel system pressure regulator that helps to transfer the fuel from one side to the other on the saddle fuel tank.

It is not an easy job and if you have a lot of salt on the roads where you live, the sub-frame and mounting bolts could be totally rusted in.

Neil.

Post by **jimmy57** » 10 Oct 2018, 20:20

The fuel pump is on passenger side with a venturi "pump" (volvo calls it an ejector pump, a name they use in the water well biz too) on the LH side to push fuel on that side to the RH side when the tank gets lower. There is a fuel line that leaves the RH side and goes over to the LH side sender/ejector pump device and a line that comes back to dump the fuel in RH side fuel pump "cup". The fuel pump goes in tank on front of RH side. If the fuel is coming off the top rear then it can be one of those lines. At this age in an area where they use salt or mag chloride in winter you could have rusted pieces.

h20ham · Post by **h20ham** » 11 Oct 2018, 00:00

Most likely I will cut a hole in the passenger side in front of the ejector
Thanks

Post by **scot850** » 11 Oct 2018, 08:01

Naturally if you do this be very careful of sparks!

Neil.

h20ham · Post by **h20ham** » 11 Oct 2018, 08:19

For sure, thanks. I have a air powered nibbler

Post by **jimmy57** » 11 Oct 2018, 12:45

Cutting the floor is WAY not cool. You end up with a weak point not sealed well and any fuel leakage and fire in accident is going to have entry into car quickly. If you find that the leak is not at the sender then the tank has to come down partially to do anything about that. The vertical parts of the floor are structural as stiffeners for the otherwise flat floor.
The tank will come down if you remove the forward bolt on the diff extension housing. The exhaust pipe over LH axle will need to come off. The trailing arm on RH side is detached at lower control arm and then the bracket that holds the trailing arm at front is removed. When the tank straps are removed the tank will be resting on diff ext housing and you can pull the RH side down and you will be looking at the RH sender.

Post by **wizechatmgr** » 12 Oct 2018, 19:29

If you can find someone that has a borescope with a flex cable you may be able to push into one of the access points on top of the tank and look around without dropping the tank. This will at least allow you to better pinpoint the location of the issue, possibly even identify the actual issue.

h20ham · Post by **h20ham** » 25 Oct 2018, 19:56

Hello
I haven’t cut the floor yet, as one of the leaks appears to be a metal section of fuel return line.
Outside drivers side of fuel tank. Is this the return line?
I suspect it is, as it drips every 30 or so minutes. And has been for days!
It is worse when running.
But...The consistent drip could be from the crossover pickup Venturi hose. Or, more likely. The “O” ring which seals the Venturi/return/crossover unit.
If so and I believe this to be the case. What other systems within the rear fuel are compromised. I would guess them all. So, i need to order all new hoses..that sucks, as the return is most likely long ( i can t find the part number or description (help there please))
New O rings and fuel tank nuts.

Looks like I am dropping subframe enough to fit new clamps to clear tank

Post by **scot850** » 25 Oct 2018, 21:20

Your 98 will be a a little different to my 2000 R, but look for my rear sub-frame replacement thread. In there are a lot of pictures of the top of the fuel tank and most of the pipes. That may help you identify which one you are looking for. I know what most of the pipes do on my car, but there are a few small variations on the older AWD cars.

Neil.