1941 Fuel Pump Rod - How to?

Does anybody know how to replace the fuel pump rod an on a '41? I have low pressure (less than 2 lbs) and I understand that a new fuel pump rod will boost the pressure slightly. I lose fuel at high load and have to kick on the electric backup to supplement.

The new rods have a skirt on them that prevents me from dropping it down the fuel pump stand hole.
 

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Russ,
I have the stand removed. There is not enough clearance down in the block to slip the rod through the hole because of the skirt on the rod. Any other thoughts?
 
You may have to trim the skirt down unless you want to remove the intake manifold. Will the existing one pull out? If so, the replacement is too large.
 
turn the rod end for end the skirt goes on the top and is designed to help prevent engine oil from splashing up the vent breather
 
Edit: Retracted my stupid response! That's what I get for trying to do several things at once and not paying that much attention to what's really the problem.
 
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Do you have the thin metal cylindrical baffle removed from below the fuelpump stand??
 
A "field expedient" for increasing pressure back in the day was to cut a leather pill the size of the rod's diameter and insert it into the cup on the pump.
 
If you pull the old one out it should bring the outer baffle assembly with it.

The rods are made with hardened ends pressed into a tubular centre section. I have lengthened them before now by pulling the upper end off, inserting a washer and refitting the end.

Mart.
 
Under the fuel pump stand is a metal tube with baffles, when the stand is removed the tube can be removed by pulling it up and out of the engine. The old and new pump rods can then be removed and inserted. One more item is the thickness of the gasket at the bottom of the fuel pump stand. Do not use anything over ABOUT 0.015" thick, the thinner the gasket the higher the pump output, it can make a big difference.
 
Maybe the attached will help explain. With the fuel pump stand removed, when I look down into the block, there are metal fins that surround the rod preventing the old rod from pulling out. The skirt hits the fins preventing removal. I assume the fins are there to prevent splash.

I assume there is a way to replace the rod without breaking the engine down. Thanks for your suggestions - all are welcome.

Len
 

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That metal with the fins will come up. Scrape the gasket off and you the outline of that tube, with a small screw diver you can pry it up. Walt
 
Do what Walt says. Look for the flange of the metal baffle tube. tap it gently back and forth then lift it out. It's a light push fit in the chamber.

Like I said, grab the rod and pull it. If it doesn't pull apart, it will lift the baffle tube out.

When you see it it will all make sense.

It's the 6756 part in this illustration from Mac Van Pelt's site.

Flathead_Engine_complete_1937-38.jpg



Mart.
 
Walt/Mart
I have removed parts 9415-Assy including part 6756. I can look down inside the engine and see part 9400. I can't see the skirt on 9400 (pump rod) because there are two pieces of metal, one around 2 inches below top and the other around 4 inches below top, that surround the pump rod. Part 6756 (Fuel Pump Tube) fits between these two pieces of metal when I reinstall the 9415 Assy.

The two tangs appear to be there to keep oil from splashing, but keep me from pulling to pump rod out the top.

Could this be unique to 1941 Fords?
 
No, I think you are getting the parts mixed up. There is a smaller diameter tube - about 3/4" diameter that is normally press fitted into the base of the fuel pump stand. This fits down the inside diameter of the baffle tube, and the pump push rod fits down the inside of the 3/4" tube.

If you look at the base of the fuel pump stand you should see a step in the face. the recessed part towards the middle is like that so it can capture and locate the flange on the top of the baffle tube.

I'll look for a picture online of the baffle tube.

Here's a couple from the hamb.

From the side.
1937_ford_flathead_v8-121-jpg.1671370


The view you can see:
1937_ford_flathead_v8-123-jpg.1671371


You need to get something under that flange and pull it out. It should rock a little side to side first, it's not a tight fit in the manifold.

This thread on the hamb describes the same thing:

http://www.jalopyjournal.com/forum/threads/flathead-fuel-pump-pushrod-wont-come-out-help.709122/

If you can't see the flange you might have a tube from a short manifold and a tall manifold in place, with the baffle tube fitted below the manifold instead of through it. You will need to remove the manifold and fit the correct tube if that is the case (unlikely).

Mart.
 
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Ding Ding Ding. OK Mart - I can see what you are talking about. That looks like what I have. I will get something under the flange and remove the tube. Then I suspect the rod will come out with no problem

Thanks - I'll let you know.

Len
 
I had a ***** of a time getting mine out. Someone in the past had bent that baffle and then probably tapped it down into place. I just kept pulling up on the rod and it finally came out. I bought a new rod and found another baffle tube to install. Worked fine.
 
OK - the baffle tube is stuck solid. When I pry up on the rod, the apron slips. I have tried getting something into the baffle tube and rocking it but I have not been able to move it. I am using penetrating oil - still no luck. I suspect it has never been out.

1) Should I go ahead and pull the rod out letting the apron slip off and hope I can remove the baffle and retrieve the apron out of the block?

2) Is there a tool that can pull these out?

Any help is appreciated.

Len
 

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