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New tank filler neck gasket problems

RBCharger

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New AMD tank, correct sender (3/8") all ready to go. Warmed up the filler neck gasket in hot water, fitted it to the tank then tried to insert the new filler neck. No dice. The diameter (OD) of the filler neck is the same as the old one (2") and the id of the gasket is 1.83". The OD of the gasket is 2.32" so difference is about .49 on the ID so thickness of the gasket must be .25. Methinks this is not gonna fit with this gasket. Thoughts?
 
Why would you warm the seal up in hot water? I have done 100's and never heated one up.
 
They fit tight for sure. Heating /warming the gasket expands it making it worse.
Freeze / cold the neck then lube the **** out of it with clean engine oil. Should slide right in.

Where you at in NoCo?
 
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I had a hard time with it. I think I used light oil or wd 40 and kind of pushed it straight on . Really had to push with someone holding the tank . Finally got it on. But took awhile. Had the tank out while we did it
 
Make sure you have the beveled edge facing up. Sometimes it is hard to tell, but there is a difference.
 
Why would you warm the seal up in hot water? I have done 100's and never heated one up.

I was attempting to get the gasket to compress while I tried to shove the filler neck into the tank. This tank and gasket were new about 10 years ago so and weren't installed. The gasket it pretty hard in my opinion. Are those gaskets a harder rubber or more pliable?
 
Here is my thread again, where I had a filler tube grommet that was IMPOSSIBLE to use. Some are apparently manufactured wrong. I found one that worked after fighting the first one that didn't.... EDIT> The one that did work is this " Inline Tube # INL 14517".
https://www.forbbodiesonly.com/mopa...ommet-is-too-tight-to-insert-the-tube.227169/

This is very helpful - I think the gasket and tank are about 10 years old but weren't installed. This gasket looks the same from both sides and as I stated I think the thickness is wrong just like you experienced. Too bad there aren't more NOS parts for our mopars, because some of these parts are terrible for being "restoration" quality.
 
I had a hard time with it. I think I used light oil or wd 40 and kind of pushed it straight on . Really had to push with someone holding the tank . Finally got it on. But took awhile. Had the tank out while we did it

I was concerned about how grease or WD40 might degrade the gasket so I used plain old water. The tank is out of the car and I tried getting that thing shoved in for at least an hour with no luck.
 
They fit tight for sure. Heating /warming the gasket expands it making it worse.
Freeze / cold the neck then lube the **** out of it with clean engine oil. Should slide right in.

Where you at in NoCo?

Ok, I'll give that a try. I'll PM you on my location.
 
Well I looked for the part number on the gasket and I measured the tank hole - it's 2.25". The grommet number is MF296 by OER. That shows at the correct grommet for the filler neck. I tried again with some silicone spray and no dice. I just ordered a new one from DMT.
 
Try putting seal in a freezer before pushing it on. We really had to push it on. Tried twisting it . Had to really push and turn a bit to go on.pushed it flush with the hand but it should go.
 
Think about it. Freezing the gasket will shrink the outside diameter making it easier to put in the tank but make it harder to put the tube in the gasket. Freezing the gasket may make it brittle and it isn't really the problem.
Insert it into the the tank freeze the neck, oil the **** out of it and try to insert.
You have a chest freezer right? Should fit the neck easily. Leave it in there for a couple of days....or more.
Every Colorado boy has a chest freezer. Needed for Elk from the fall. :D

I have a DMT gasket on my Runner, worked fine.
 
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Think about it. Freezing the gasket will shrink the outside diameter making it easier to put in the tank but make it harder to put the tube in the gasket. Freezing the gasket may make it brittle and it isn't really the problem.
Insert it into the the tank freeze the neck, oil the **** out of it and try to insert.
You have a chest freezer right? Should fit the neck easily. Leave it in there for a couple of days....or more.
Every Colorado boy has a chest freezer. Needed for Elk from the fall. :D

I have a DMT gasket on my Runner, worked fine.

I just tried this with no luck. The tube will not insert into the tank/gasket no matter what I try to do. Froze tube overnight, used silicone spray...nada.
 
I put the gasket in first and then the tube. The tube goes in fairly easy once the gasket is in. I think we got a a start on the gasket and then pushed . But with no tube.
 
I just tried this with no luck. The tube will not insert into the tank/gasket no matter what I try to do. Froze tube overnight, used silicone spray...nada.
****, they definitely can be a pure bitch. I agree with 69 Runner above.... worth a shot.
If not then maybe the DMT gasket. I remember with my son's Duster we took a Dremel with a small sanding drum on it and scrubbed out the center a bit to get it to go. If I remember right a 2x4 block and dead blow was needed to help persuade it but we eventually got it in.

Keep us posted.
 
I've tried this silly gasket each way - doesn't make any difference. Hopefully the DMT gasket will be here by Friday then I may resort to BFH.
 
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