New sending unit leaks at lock ring

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4spdcuda66

4spdcuda66

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Just put a new fuel sending unit, gasket, and lock ring on my 67 Fury, and it leaks terribly at the lock ring. The ring is on as tight as it will go, and there is play in the sending unit when I grab the outlet tube and wiggle it. The gasket is sitting flush in its recess with no kinks or overlap, and the lock ring is turned to its limit. Any ideas what's going on here? Thanks.
 
Very common on repo lock rings. There was a guy on here selling some original lock rings....you could go original. What I did was take the lock ring off and bend the tabs in a way that made the ring fit tighter. Is the original lock ring still around?, use it. Two gaskets don't work as it makes it to tight to turn the lock ring.
That's my experience with this fun and enjoyable job of gas tank R&R, someone else may and will likely have some other idea :)
 
marksmopar1 said:
Very common on repo lock rings. There was a guy on here selling some original lock rings....you could go original. What I did was take the lock ring off and bend the tabs in a way that made the ring fit tighter. Is the original lock ring still around?, use it. Two gaskets don't work as it makes it to tight to turn the lock ring.
That's my experience with this fun and enjoyable job of gas tank R&R, someone else may and will likely have some other idea :)
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Yeah, I still have it. I'll try the old ring, and if that doesn't work, I'll try bending the tabs.
 
I had to replace the sending unit on my daughter's 74 Dart. The new gasket didn't seal properly so I went to a real hardware store and bought some sheet stock fuel-resistant rubber that was a little thicker than the replacement gasket. I used the old gasket as a template and cut my own gasket. I used the original locking ring as it was and it was very tight when it hit the stops. There were no leaks.
 
They all do it. You have to bend the tabs and tighten them up.
 
Thanks for the replies and info. You've all given me some solid options to check out. I'll let you know how it turns out when I get it right.
 
I put one in mine with the 1/2 inch pickup. The original wasn't working. The new one doesn't seem to be real accurate. Now it has quit working. I have to ohm it out now and see what the problem is
 
are you guys using the lock ring wrench or are you just hitting the tabs with a screwdriver and hammer? i dont have the wrench and i cant seem to get the snap ring on fully to the stoppers. it's about an 16th away from the stopper. as soon as i put gas in it's leaking. i did use the original snap ring with the new rubber gasket provided
 
insidegroove said:
are you guys using the lock ring wrench or are you just hitting the tabs with a screwdriver and hammer? i dont have the wrench and i cant seem to get the snap ring on fully to the stoppers. it's about an 16th away from the stopper. as soon as i put gas in it's leaking. i did use the original snap ring with the new rubber gasket provided
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Necro-thread revival! :)

I know what tool you're referring to. I don't think I've ever seen anyone use it. I have a spanner wrench that fits these, but I typically just use a punch and knock it home.

Not sure where you got your setup from, but those Chinese lock ring repops are hot garbage. I've never had one that didn't leak. There's a vendor on here that sells the NOS OEM ones. I think his name is Halifaxhops. I get mine from him
 
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Get the rubber gasket from DMT (I linked it in my previous post). Most of the repop gaskets are too thin.

You don’t need an OE lock ring either, although they’re easier since you usually don’t have to tweak anything. But even with the cheap repop lock rings you can bend that tabs on the lock ring to change the tension on the gasket.

I have used the spanner too, it can make things easier with the limited space available especially on the A-bodies. But most of them are pretty cheap and don’t fit all that well either. If they fit well it’s a good tool, but most don’t fit well enough to be worth it.
 
As noted you can make any lock ring work and make sure you have a good seal. I smear pst592 on the seal to help seal it and for the lock ring to rotate without dragging the seal along. Never had a leak.
 
Use a long screwdriver that "hits" 2 tabs and twist/pry. I put new seal in and it leaked like a ***** on payday. Put the 50+ yr old gasket back in, leak gone.
 
4spdcuda66 said:
Yeah, I still have it. I'll try the old ring, and if that doesn't work, I'll try bending the tabs.
Click to expand...
It should work. I had this most aggravating scenario happen to me also, leaked like a sieve using new parts, put old lock ring back on and problem instantly solved. When you make the swap, look at the two rings together, very evident what the problem is. Sad the aftermarket cant manufacture this stuff correctly, especially considering they only have to copy it, not invent the concept.
 
Sorry, just realized the vintage of this post! Lol
 
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