Fuel pump

Gents,

The fuel pump on the 56 cj5 has a bad diaphragm. Is it dumb to look for a rebuild kit or do I just need to sack up for the new replacement!?

 

Personally, I like rebuilding them.

 

I needed one in a hurry 2 weeks ago for my '56 CJ6. I got a suitable replacement at the local parts house for $38, installed it and was running the next day. I plan to rebuild the original and put it on the shelf as a spare.

 

Well, I'm in no hurry so I think I'd like to rebuild it! I'll search for a kit, and keep the local parts store in the back pocket!

I'm a little green here, would any like sized local pump work if I went that route?

 

You didn't list an engine size, so I'll assume it's stock. Give them the year and engine size, '56 CJ5 F134, that should bring up the pump you need. I had to rearrange the fuel lines a bit and use a shorter bolt for the front bolt since the flange on the replacement pump wasn't as thick as the flange on the original. The original bolt bottomed out in the hole before it was tight.

If your local parts house can't get you one, Walcks lists a replacement w/glass bowl and w/o vacuum for about $45. They also carry rebuild kits. http://walcks4wd.com/

 

"the flange on the replacement pump wasn't as thick as the flange on the original."

This is one reason why I'd go with rebuilding. Different pumps may require a spacer under the flange, to get the lever length properly located on the camshaft, etc.

Search here for rebuilding tips. The first time, it can be a little tricky unhooking the diaphragm rod, etc.

 

Thanks for the info!

I will certainly do my research before taking it all apart for the rebuild. As always, I'll post more questions if need be!

 

I'm glad you brought this up Pete. This is another one of those areas I'm learning more about as I work on different old Jeeps. I am and probably always will be an apprentice when it comes to working on old Jeeps, so I welcome info and suggestions from others.

The pump on the left is the one I took off the '56 CJ6, the one in the center is what I replaced it with, the one on the right is the pump that I just took off a CJ3A L134. One thing I noticed is that the center of the worn spot on the pump arm of both the one on the left and the one on the right is 1 3/8" from the flange. That tells me they're both hitting the cam at the same spot, even though their arms are different shapes and lengths.

The replacement pump is an Airtex #572 according to the box. The gasket for it is a Fel-Pro #6579. I've been using the CJ6 every day since I put it on last week and so far it seems to be working okay. I just bought the one in the picture to replace the pump on the L134 because it started leaking while I was driving it this morning.

 

It may be more a case of getting the "throw" length of the lever arm at the right distance from it's pivot, and thus getting the correct amount of action...

I'm no expert on these details, but it has been discussed here in the past.

 

@jbjeeps

Thanks for posting the pic, and giving me more insight in general. The amount of info I'm gaining from a single query really is the best part of this forum!!

Hell, at this rate I may be driving a jeep one day. Haha

 

Driving my old Jeeps is the best way I know to find out what needs to be fixed next.

Glad it helped, I'm learning right along with you. As I understand it, the issue is getting the right fuel pressure to the carb. A fuel pressure tester will help figure out what's there and a regulator will help to set it correctly. The spacers help lower the pressure if it's too high. IIRC these carbs need very low pressure, around 3 (?).