1998 V70 Gas Leak From Tank

Post by **SonicAdventure** » 23 Sep 2015, 14:25

I have a 1998 base V70 with a newly discovered fuel leak.

Prior owner put a fuel pump in about 6 months ago, I have not noticed any error lights or fuel puddles till the other day.

I filled the tank up all the way, and I drove it to my mechanic for an oil change. Parked the car on a compound, slight incline where the rear passenger corner was the lowest point in the car. After about 10 minutes of being parked, a Frisbee sized puddle of gas appeared right below the fuel door on the ground. It was still dripping fuel, but I could tell from where. Mechanic wants 3 hrs labor to drop tank, but I don’t have the money to do that now. Isn’t there a fuel pump access panel in the rear hatch?

Since I’ve owned the car for 3 months and this has never been an issue I assume that it’s a loose filler neck or fitting on the fuel pump, but it seems to be aggravated by the fact that it was on such an incline and totally topped off. Granted I know a fuel leak must be addressed, but what should I check first?

Post by **oragex** » 23 Sep 2015, 14:35

Don't think the tank itself is rusted. If budget is tight, I would just keep from fully filling the tank.

If there is a more severe issue, it will easily get noticed by a constant gasoline smell.

Post by **cn90** » 23 Sep 2015, 15:02

I summarized all the causes of fuel leak in one thread. the good news is all of them are cheap fix.
See the post from 27 Nov 2013:

https://www.matthewsvolvosite.com/forums ... =1&t=60269

Post by **scot850** » 23 Sep 2015, 15:02

The AWD tanks are plastic, are the FWD ones not also? If that is the case, then a rusted tank should not be the issue. If the PO replaced the fuel pump, one of the mistakes many do is not replacing the pimp to tank seal and the plastic nut that holds the pump in. There should also be a large ring clamp around the plastic ring to prevent it cracking and breaking with age. Most cars I have seen in PnP that presumably have had the pump replaced are missing the clamp.

So remove the cover for the fuel pump and see if there are signs of fuel leaks around the pump. It could also be a leaking fuel pipe connection. All-in-all, I have doubts that that would be the issue if it only appears to leak when full as the pump is lowest point is about a 1/4 of the way up the tank.

Neil.

Post by **erikv11** » 23 Sep 2015, 17:18

Yes, the FWD tanks are plastic. They are super light when empty or partially empty!

I have ever seen anything around the plastic nut on any FWD cars, and I have looked at a lot of their fuel pumps. Maybe Neil is referring to an AWD thing?

Anyway, all of the leak types for a FWD are indeed clearly spelled out in the link from cn90, check it out.

Post by **dosbricks** » 23 Sep 2015, 18:51

I just removed the vent hose on my 850 because I thought it was leaking. Not finding any cracks, I plugged it and pressured it up with 20 psi air and placed it underwater--no leak. I put it back on, and being disgusted

by all the places the top of this tank can leak, decided to just not deal with it and continue to not fill the tank to the top.