850 fuel tank lock ring

Teddy1975 · Post by **Teddy1975** » 15 May 2017, 08:43

What does one do if the locking ring on the fuel tank which holds the fuel pump in place has been left off for more than the Volvo recommended one hour only?

In my case it was a broken ring that has sat on the fuel tank for more than 1.5 years, making the part with the threads too swollen for me to screw on the ring.

Post by **Ozark Lee** » 15 May 2017, 14:30

That ring is very difficult to get lined up without it trying to cross thread. I don't think leaving the ring off for a period of time will cause the tank to swell.

...Lee

Post by **tryingbe** » 15 May 2017, 17:30

Buy a new ring.

Post by **erikv11** » 15 May 2017, 20:14

He got a used (but working just fine when removed) ring. Seems like it should work fine? Hmmmm.

Post by **abscate** » 15 May 2017, 21:13

Whats up with the one hour recommendation for the lock ring? Can someone give me the third grade version of that please?

Post by **rspi** » 15 May 2017, 22:48

I wouldn't worry about it. Just put the replacement ring on.

Teddy1975 · Post by **Teddy1975** » 15 May 2017, 23:42

The new used ring itself is fine Erik and tryingbe, it's exactly the same size as the cracked one I've had to put on again with a zip tie holding it somewhat in place like a PO had done.

The one hour recommendation is from VADIS, to prevent swelling of the lip with the thread on the tank, do not leave the ring off for longer than max an hour, but no info as to what has to be done if it's left off for more. I'll give it another try later as the broken ring just isn't tight.

Thanks for your input,
Teddy

Post by **JimBee** » 16 May 2017, 12:09

Last time I changed a fuel pump the ring, which had apparently never been off since the car was new, came hard all the way. To make it easier to screw back on I sprayed the ring's threads with silicone as well as the threads on the tank neck. It spun back on quite easily.

Teddy1975 · Post by **Teddy1975** » 16 May 2017, 13:12

My problem yesterday was the ring would catch the start of the thread then twist and pop off on the opposite side. The only other time I've had to do this was on my 740, which was a breeze compared to this.

I raised the car and was about to drop the tank just to get more space to work in, but even the simplest things on this car has been made nearly impossible by previous owners shearing bolts, epoxy gluing things back together and whatnot.

Anyway, I'm considering fabricating a tool, but both my angle grinders are lent out to friends and all I have available for cutting anything is a dremel. Would something like this for an oil filter work instead? It can extend to 13.6 cm.

Post by **Ozark Lee** » 16 May 2017, 14:23

The problem with the oil filter wrench is that it tries to deform the ring as you torque down on it and then it wants to bind. There actually is a specially made wrench to do the job that sells for about $35.00. Google "Schley SL 69800" and you can see what they are doing.

...Lee