gas leak from around left side sending unit Topic is solved

[abscate]

If you ever have to do repairs , BlackBart in Montana identified the actual plastic in use and successfully hot welded a leak on his in a recent thread, maybe 2019

[jonesg]

I think you just rolled the seal, it helps to lubricate it during install.
Can also leak if the locking ring isn't tight, I tapped mine home with a piece of wood and hammer.

[gnalan]

I borrowed the lock ring tool last time from AutoZone, and torqued it down after everything was put back together. I also used Vaseline when I installed the seal.

What do you mean by tapping it home with a piece of wood and a hammer?

[gnalan]

I rented the tool again, from AutoZone, and removed the plastic ring, and pulled the sending unit up. The seal's diameter was too big to fit into the groove, but one of the other two I had laying around fit perfectly.

I also noticed a lot of dirt under the seal, which I don't think I saw last time. I used Vaseline and qtips to pick up the loose dirt, without it falling into the tank. I used soapy water to clean the threads up on the plastic ring, and on the tank. Got it all cleaned up, lubed things up with some more Vaseline to help it all go back together ok, and tightened it all back up.

Rain started before I could check with VIDA to see if it still shows a large EVAP leak, using the fuel pressurizing feature. A lot cheaper than filling the tank at $2.70/gal just to see if the leak is gone.

If the pressurization feature in VIDA is still showing a large EVAP leak, like the leak around the sending unit, will using soapy water around the sending unit show if it's leaking still or not? Will anything work better than soapy water, or should I just fill the tank and hope for the best?

[volvolugnut]

Soapy water is a great leak detector if you have a couple PSI in the tank.

volvolugnut

[gnalan]

I ran the quick test with VIDA, and in the "status/DTC1" window it says "Large leak" and under that "Limit DTC 1 = 254". No actual DTC code to lookup. In the "status/DTC2" window it only has an equal sign.

Not much help from VIDA, unless someone knows what the above means.

I did use a piece of wood, and a hammer, to try to tighten the ring more. All that did was break 4 different tabs off, so I think it's as tight as it's going to get. I can still smell gas fumes coming from around the sending unit, so I'm pretty much lost on what to do now.

Anyone else have/had this problem, and have a working solution to fix it?

[cn90]

The O-ring PN is 9183708. Genuine Volvo is certainly the best but it is $25.
Aftermarket O-ring is about $8-$10, but it is a gamble.

Maybe you can take your O-ring and go to local parts store, but I doubt they carry this odd size.

This Video discussed all this stuff:

[gnalan]

9183708 was the one I ordered, and it was too big around to fit inside of the groove. I removed that one, and used on of the two used ones I took off when I replaced the fuel pump. It fit perfectly inside the groove.

VIDA wasn't much help in checking for leaks, so I guess I'll fill the tank up and hope for the best. If it still leaks I'll have to figure something else out to get it to stop.

91/93 octane isn't as cheap as 87 is, but my car doesn't run too well on 87. Only getting 135 miles out of 7/8ths of a tank isn't cheap either, so I really need to get the leak stopped if it isn't already. I'll find out when I fill the tank again.

[cn90]

Is the plastic top of the sender unit cracked?
If so, you may need an entirely new sender unit: Volvo ($110) vs aftermarket ($35).

[gnalan]

Nothing is cracked anywhere, I triple checked it all before I put it back together. Sending unit is smooth top and bottom, top of the tank is smooth, and the plastic ring is smooth. All of the dirt has been cleaned up, and I lubed it all up with Vaseline before putting it back together.

He showed in the video using the same tool that I used, but I didn't use a breaker bar on mine. All it took was a few taps from another wrench to loosen it up. After I tightened it down with my ratchet, as suggested above, I used a piece of wood and a hammer to try to fully tighten it. It didn't look like it turned any just by doing that, so I'm wondering if it's just not tightened down enough. He didn't show how he tightened his ring down. Should I put a long breaker bar on my ratchet and tighten it up more than I already have? I don't want to break/crack anything, but I also don't want to have to keep taking things apart if all I need to do is use more leverage to tighten it the rest of the way down. How do I know when it's tight enough, besides the old adage "wait until it breaks something, and then back it off a little"?