87 2.5 Fuel Sending Unit Replacement and Pump Compatibility

[jamcomanche]

Looking for some help on compatibility with my 87 2.5.  My fuel pump is on it's death bed and I had ordered a replacement US MOTOR WORKS USEP7006 which did not fit in the existing sending unit at all.  The sending unit on my truck has an upper pump retainer bracket, and appears to use the EFPK-3210 pump.

Not only was the US Motor Works pump inlet shorter and wider, but the unit body was too short to be secured with the retainer. I've started a return for that and in the mean time ordered a complete JPSU-6P4 sending unit from ebay because I couldnt find the JPSU-6P2.5, but I'm trying to actually figure out what the best direct replacement would be. 

I have been thinking that the person who owned the truck previously may have used a Cherokee sending unit, which is not listed as compatible with the MJ anywhere...

Here is what I've found
 

JPSU-6

Notes: Does not have upper pump retainer
Listed Compatibility:

1.  87 MJ 2.5 using pump EFPK-3210 
2.  87 MJ 4.0 using pump EFPK-3204 

JPSU-6P2.5

Notes: Does not have upper pump retainer

Listed Compatibility:

1. 87 MJ 2.5 using pump EFPK-3210 

JPSU-6P4.0
Notes: Does not have upper pump retainer
Listed Compatibility:

1. 87 MJ 4.0 using pump EFPK-3204 

JCSU-8790
Notes: Has upper pump retainer
Listed Compatibility:

1. 87 XJ 2.5 using pump EFPK-3210 

JCSU-8790P2.5
Notes: Has upper pump retainer
Listed Compatibility:

1. 87 XJ 2.5 using pump EFPK-3210 

Does anybody out there know:
  1. if there is a reason the XJ units are not listed as being compatible with the MJ?
  2. if the JPSU-6P4.0 will fit and work in the 2.5?
  3. the best place to purchase one of these

Thanks guys!

[eaglescout526]

Pic of your original unit? 
 

I’ve got quite a few work arounds and info. 
 

23 and 18 gallon share the same sending unit. REGARDLESS! Of the engine. 
 

16 is unique. 
 

Pumps are pretty much the same between all. 
 

Now 86 is the odd ball year and has a completely different sending unit and partially because it was easy to have one model. It wasn’t until the 4.0 where AMC made one sending unit across the board for the MJ. 

[jamcomanche]

10 minutes ago, eaglescout526 said:

Pic of your original unit?

Thanks for the response eaglescout. Attached a photo (it's not my unit, but is the exact unit I have). Note it has the upper adjustable retainer bracket and EFPK-3210 pump. Mine is in much worse shape
 

[jamcomanche]

Also just noticed, the ebay listing for this unit says 13.5 Gal haha https://www.ebay.com/itm/184914035537

[eaglescout526]

Yeah thats an XJ one. I went through the same issue as I was running an 86 sending unit on my XJ. Theres a Bosch pump that will fit the early sending unit. I need to find the box that mine came in. 

[jamcomanche]

4 minutes ago, eaglescout526 said:

Yeah thats an XJ one. I went through the same issue as I was running an 86 sending unit on my XJ. Theres a Bosch pump that will fit the early sending unit. I need to find the box that mine came in. 

This truck has all kinds of mixed parts on it. I should have learned by now to pull the parts before I order new ones. 
Thanks for the help! No rush on the info. I appreciate it whenever you can get around to it.

[eaglescout526]

 

Amazon carry’s this. 

[jamcomanche]

13 minutes ago, eaglescout526 said:

 

Amazon carry’s this. 

Thanks! It was a direct replacement? The wiring and outlet look different, if this is the one you are talking about
The retainer bracket has a specific shape where it fits around the upper connections too.

[eaglescout526]

Yes it is. I have an NOS 86 unit in my 88. It fit just fine. If I can find pictures of it I’ll post it but I don’t remember too much since that was years ago. 

[eaglescout526]

Well it turns out I never took any pictures of the sending unit. But I swear it took the Bosch pump just fine with no modifications and looks like the one from my XJ. It also has the straight pipes like the XJ unit.