Fitment issue #1 with DMCH fuel pump/sender module #107000

[Henrik]

I am having an issue with the fitment of my new fuel pump/sender module part #107000 from DMCH.

The pump works great, the fuel meter seems OK - no issues with the product itself. The issues I am having are:

ISSUE #1:
1) The pump is not seated all the way down into the hole. As you can see in this video, the O-ring is not in compression (yes, this video is shot with the clamp removed but the pump did not move after I had loosened the clamp.) While re-installing the clamp I pushed down on it with my full body weight on a 2 x 4. Still, with the O-ring not being in compression, will it leak if I fill up the tank? Would a second O-ring help?

http://www.youtube.com/watch?v=RCj9BEi02r8

IN CASE YOU'RE WONDERING: YES, THAT IS NPR'S CAR-TALK YOU ARE HEARING IN THE BACKGROUND :)

[Henrik]

ISSUE #2:
2) No matter how I index the pump, it interferes BIG TIME with the "Tank Inspection Cover" #105168. Check out this video.

http://www.youtube.com/watch?v=Bm8WrhVHwFk

Here is also a picture showing how the top of the pump pretty much lines up with the bottom of the tub where the spares wheel sits. Is my fuel tank sitting to high up?
25645

[kings1527]

Henrik,

I don't remember having this problem, particularly with getting the pump to seat properly and seal. I'm sure you have everything properly seated inside the tank and the spring system inside is compressing properly. You definitely have to have a good seal there in order to maintain rest pressure. That pump should be able to compress completely in order to get the firm seal you need.

On the second video, my cover is definitely a tight fit but it wasn't easy to tell in your video how tight it was. With mine, I had to use very mild 'force' to get all of the screws to fit but it was never an issue. It was just a very tight fit.

[Henrik]

Thanks Alex. Right below my second video: Look at that picture where you can see the relative difference in height between the fuel pump and the tub. Is my fuel tank sitting to high up?

[Bitsyncmaster]

Try using a ruler to measure your tank and compare to the pump height.

[DeLorean03]

ISSUE #2:
2) No matter how I index the pump, it interferes BIG TIME with the "Tank Inspection Cover" #105168. Check out this video.

http://www.youtube.com/watch?v=Bm8WrhVHwFk

Here is also a picture showing how the top of the pump pretty much lines up with the bottom of the tub where the spares wheel sits. Is my fuel tank sitting to high up?
25645


Yep, I remember having this issue. Drove me nuts at first; you are only the second person I know other than myself to have run into this problem.

Quick solution: put in the top middle bolt of the cover into place, then do the corner bottom ones and slowly put in all the rest. It is tough, but it is doable.

Full solution, the fuel tank is mounted too far forward. It needs to be inched back a lil' bit. That means taking out the fuel tank shield (preferably with an empty tank and moving the tank back towards the windshield.

[Henrik]

Try using a ruler to measure your tank and compare to the pump height. So.... measure between what two points?

[Silverbullet]

I can see you got the band clamp on top of the White flange... but is the bottom side if the White flange resting on top of the Fuel Tank nipple... needs to be all the way down...

Craig

[Henrik]

I can see you got the band clamp on top of the White flange... but is the bottom side if the White flange resting on top of the Fuel Tank nipple... needs to be all the way down...

Craig

Agreed, but that's just the crux: The pump won't go all the way down/in. It's like the ID of the fuel tank nipple is too small....

[jawn101]

When I did mine, I had to really lay into the top of the pump to get it to seat into the hole properly. The assembly compresses on installation and the gap you are seeing between the top of the tank hole and the bottom of the pump body (where the gasket is not being compressed) is not normal. If you really put your weight into it (carefully, of course...) it should compress down and allow you to install the clamp properly. Everything otherwise looks OK to me from what you've provided.

[Henrik]

Yeah, Jon, I did just that. I pushed down on the pump with a 2 x 4 propped against my shoulder. Oh well....

[jawn101]

Yeah, Jon, I did just that. I pushed down on the pump with a 2 x 4 propped against my shoulder. Oh well....

Oh, jeez. I wonder if there could be some kind of misalignment between the upper pump and lower baffle half that's preventing full compression. Or maybe some kind of fuel safe lubricant on that gasket would help things slide together (no idea what one would use though)

[NightFlyer]

Are you sure you're not bottoming out the baffle against the stock/OEM baffle stud? Although, the compressability of the assembly shouldn't make that a factor, it can't hurt to check.

I'd pull it, make sure that the assembly is freely compressing and retracting as it should, and try re-installation, following the supplied directions to the proverbial 't'.

Absent that, not sure what I could say that would help any...

[Silverbullet]

Ok, you have a early car... and I think I remember reading that the nipple on the early tanks was SMALLER, maybe you should remove the pump and measure it against a later stock size.... You may need a new fuel tank...

Craig

[NightFlyer]

You may need a new fuel tank...

Or he could just carefully trim some plastic off the mounting flange of the pump with a razor blade so as to make it fit the smaller opening of his tank...

[Rich_NYS]

If you disassemble it, you should be able to measure everything and find where it's going wrong. Especially measure where Josh mentioned to see if it's bottoming out.

[DMCH James]

If you disassemble it, you should be able to measure everything and find where it's going wrong. Especially measure where Josh mentioned to see if it's bottoming out.

Tank opening on the later tanks is 3.875"