Fuel Pump rebulding

Cacti_Ken · Post by **Cacti_Ken** » Sat May 30, 2015 8:16 pm

Has anyone rebuilt an AC 4260 which has a primer lever and replace the middle body with a body without the primer lever like my photos show.

I want to order a rebuild kit, but I don't know what the AC pump number is for the duel action pump used on the M38

Post by **wesk** » Sat May 30, 2015 11:46 pm

The original M38 pumps (AC #'s) were:

1539917 - After eng serial 74419

1539585 - Eng serials up thru 74419

The service replacements for these were:

5592659 - Eng serials after 74419

5592147 - Eng serials up thru 74419

M38A1 pumps in order of appearance:

1539810

5594069

5594260

All you need to do is build the pump either way using the parts list in the two ORD 9's to make sure you use the right parts with the pump you are building.

OKCM38CDN · Post by **OKCM38CDN** » Sun May 31, 2015 6:21 am

If I remember correctly - you can contact "Then And Now" and they can tell you how to identify the body and then they can get you the correct rebuild kit fir it... That was what I did years ago...

There is a number 4 digit stamped into the body along one of the edges that tells them which kit to use...

Hope this helps...

Post by **wesk** » Sun May 31, 2015 8:53 am

Ken,

As you can see from my pump list you have the last M38A1 pump I listed PN 5594260 . As I have already said above you will need to use all the pump parts required for one of the four M38 pumps I listed and just order a kit for the last two M38 pumps. Or use the number off the mounting flange on your new center body.

Then & Now will assume you want a kit for whatever number you give them.

Do you have the fuel pump parts list breakdowns from both the M38 and M38A1 ORD 9's? If not download the two ORD 9's from our downloads page and print out pages:

M38 ORD 9 pages: 60, 70, 71, 72, & 73.

M38A1 ORD 9 pages: 64, 65, 66, 67, 80, 81, 82, 83, & 84.

Then select parts to match the pump with your middle body.

Cacti_Ken · Post by **Cacti_Ken** » Sun May 31, 2015 1:33 pm

A little more info:
The problem with the new center body is, that there is not a number stamped on the flange.
The box that it was packed in has a Part No. 1143735, and it came from
27 Central Ordnance Depot, London. Ontario.
The date on the box is 5-68

I got it off ebay thinking I could just swapped it out with the center body of the 4260 M38A1 pump and end up with a pump replica of a M38 pump.

Hoping the top and bottom sections of the 4260 were compatible as a what would be in a M38 pump.

I don't want it to seem like I am over explaining myself, but I probably am, so please over look that.

And so as you see I'm trying to convert the M38A1 pump to a M38 pump.
However I didn't know which kit number to order. Even if it is possible to make the conversion with the pieces I have here.

But I believe with the info you gave I should hopefully be able to now. Hopefully a big word.

Thanks Wes for the pump numbers associated with the M38 pumps.
To clear one thing up that you wrote,

" just order a kit for the last two M38 pumps"
I'm taking it you mean, to order only one kit not two kits.
A kit for either the 5592659 pump or the 5592147 pump. please concur.

I may have the pump break downs somewhere in the shop. But I think it might be easier to download another copy.

Thanks
ken

Post by **wesk** » Sun May 31, 2015 9:31 pm

Yes, I meant a single kit for either of those late service replacement pump part numbers.

I couldn't find that 1143735 part number in any of my manuals.

Cacti_Ken · Post by **Cacti_Ken** » Mon Jun 01, 2015 6:50 am

Ok, thanks

I have had this part for a few years now meaning to convert this pump. I found it sort of odd that this body be drilled and tapped for a vent fitting, would be made in 1968 and work with the M38 pump. But maybe it was really made for some other later model pumps?

Post by **wesk** » Mon Jun 01, 2015 9:49 am

I just looked at the larger file of your first photo and see where you got that part number from. It is part of the complete NSN (National Stock Number or also called NATO Stock Number). Our system does not break the full NSN down on part's tags like the Canadians did. In that NSN on your box the breakdown is:

2910 = Federal Stock Class

Country of Origin: 00, 01 would be US made, 21 = Canada

NIIN = National Identification Item Number = 1143735

The 1143735 is used to find the item in the supply system. The supply clerks will have a cross ref manual that will give them the actual manufacturer's part number for that NIIN.

Usually doing a google search using the NSN will get you a few hits but with small parts for carbs and fuel pumps you very rarely get any hits. These parts, when surplussed out,were quickly gobbled up by rebuilders to keep their shelves fully stocked. Therefore very few web sites list any info on their NSN's.

Cacti_Ken · Post by **Cacti_Ken** » Mon Jun 01, 2015 2:24 pm

I am surprised you were able to see all that from the box. Here is the close up of the box tag and the cover tag that was with it. Appreciate the help. I'm going to try my luck on rebuild and converting it. Oh, by the way the body already had valve and seals in it. But I don't know how good the seals would at their age.
Also I found these numbers inside casting, 5590450

Post by **wesk** » Mon Jun 01, 2015 8:41 pm

It would have been nice if they had at least ink stamped the machined part number on the housing.

Cacti_Ken · Post by **Cacti_Ken** » Tue Jun 02, 2015 9:51 am

I didn't know if they would be any additional help, Since they have the same prefix as the numbers 5592659 and 5592147.

BCA · Post by **BCA** » Wed Jun 03, 2015 9:13 am

Details for the parts numbers on the Canadian packaged items are:
2910-701-6403: (easy to check in ORD9 for m38 or m38A1) 1538355.
2910-21-114-3735 = 5592293, WO 118474, body assy, fuel section, w/oil seal.
Many parts shown in the American Ord 7, 8 and 9 parts books were not issued a G#, usually because they were low-demand or non-serviced items. This caused a problem when the switch to Nato Stock Numbers occurred because the NSN usually used the last 7 digits of the "G" number. Therefore the Canadian parts books generated a NSN for these parts, using the "21" Canadian country code. This allowed for all Canadian inventory to be identified by a NSN.

Post by **wesk** » Wed Jun 03, 2015 9:26 pm

Brian,

Just a couple of little things here. The number listed in the US ORD 9 for the 1538355 is not the NSN 2910-00-701-6403 but is actually the older FSN 2910-701-6403.

The correct WO # for the 5592293 is 118474. The "for service use" part which would normally replace 5592293 is 5592953 and the WO # for it is 120005.

BCA · Post by **BCA** » Thu Jun 04, 2015 9:37 am

Thanks Wes: corrections made.

Cacti_Ken · Post by **Cacti_Ken** » Fri Jun 05, 2015 1:43 pm

Then and now told me they didn't have info on these numbers 5592695 and 5592147.
I gave this number 1539917, and the lady I was talking with said it sounded more familiar. She gave me a price and for me to send a photo of the diaphragm pull rods for correct diaphragms to send in the kit.

She emailed this photo of kit to compare if it would work with mine.
To me it looks like it will. The only difference is, that there is only one pulsator diaphragm in the kit.

She will have to change the vacuum diaphragm to one with the same pull rod as I have removed from the pump.

My question here is, will this one diaphragm replace the three original pulsator diaphragms removed from the pump?
Is the diaphragm in the kit made of modern material for today's gasoline and only one is needed for replacing the three?