Holly 94 Pump Return Spring

[WarbirdPhotog]

Hey everyone, took apart my Holly 94 (the later 1940s Model 59), and I noticed that the pump does not return upwards. Before, they had a spring mounted to the accelerator arm ball joint going to the generator. Yikes! After rebuilding the carb, I noticed there's no return spring to push the pump back up. I've seen two schematics... one that shows a spring of some sort in with the Pump Operating Rod (don't know how, there's no room in that shaft), and then another with a spring under the pump that pushes it back up. Which is correct, and where can I find one or the other?

[flatjack9]

Use 37 and 96.

[WarbirdPhotog]

Originally Posted by flatjack9

Use 37 and 96.

Okay. So what's the spring on the rod? I have the spring that's on the actual pump/plunger. But that's the only spring I have in that system. Any idea where I might find that particular pump spring? I see some for sale and specialty places, but they don't look like they're for this particular Holly unless it doesn't really matter.

[WarbirdPhotog]

And, is this what I need? Seems to be for 50CC.
https://www.oreillyauto.com/detail/c...g/hly0/2010910

[nickthebandit]

Contact Charlie NY, 716-662-9159. Charlie not only has the parts, he also has the knowledge.

[Terry,OH]

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Vintage Speed in Fla has the pump rod piston spring (red pointer) as in your second photo. I am not aware of a spring that goes in the pump well.

[38 coupe]

Like Terry, OH, I have never experienced a carburetor with a spring under the accelerator pump.
Parts 37 and 38 in the second image are what you need.

[flatjack9]

Originally Posted by WarbirdPhotog

And, is this what I need? Seems to be for 50CC.
https://www.oreillyauto.com/detail/c...g/hly0/2010910

That spring is used on later 2 and 4 barrel carbs. Not meant for the 94 carbs. Don't know when they started using the spring under the pump, but it is not uncommon.

[scicala]

Originally Posted by flatjack9

Use 37 and 96.

#37 is the pump.overide spring. Not a return spring.
Sal

[Merc Cruzer]

This is from a later carb, but the concept is the same. Sometimes a picture, is better than a drawing. Hope it helps.

[jplutz]

Greetings Warbird,
There is NO spring on the outside of the "Accelerating Pump Operating Rod" #9531 in the upper illustration. The "Accelerating Pump Link" # 9526 connects #9531 to the "Throttle Shaft Linkage" # 9581.
Your pictures looked familier. In my first post I asked for info about my installed carb, which comes from a '55, sans choke. (I didn't know about it)
In an old candy tin, covered in rust and dirt was the old carb, completely disassembled. I decided to put it back together. I got most of it correct, but left out the throttle rod because the throttle plates are so corroded they don't go in the slots, same with the choke plate.
So I never connected the pump link. When I saw your diagram and the photos, I went and got the carb and the link and rod were still in the bottom of the can.
Note: #9531 has a Spring Loaded Ball inside the Hole! That is why there is a Notch in the Shaft of #9526. A clip does not go in the notch
I'll try to attach photos. JP

[Merc Cruzer]

Note: #9531 has a Spring Loaded Ball inside the Hole!

[WarbirdPhotog]

Originally Posted by Terry,OH

Vintage Speed in Fla has the pump rod piston spring (red pointer) as in your second photo. I am not aware of a spring that goes in the pump well.

It seems there's a back and forth on that here on Ford Barn. Searching threads about a return spring bring up the debate back and forth. It seems like a spring in the pump well under the plunger would do the trick, and I found one on ebay that lists that spring in that spot for the Holly 94: https://www.ebay.com/itm/362793238261

Originally Posted by 38 coupe

Like Terry, OH, I have never experienced a carburetor with a spring under the accelerator pump.
Parts 37 and 38 in the second image are what you need.

So I have both of those parts, but I don't see how that spring on the pump/plunger returns the accelerator arm. That spring just jeeps the plunger attached to the rod with the pressure of the spring and the 'cap'? on top.

Originally Posted by flatjack9

That spring is used on later 2 and 4 barrel carbs. Not meant for the 94 carbs. Don't know when they started using the spring under the pump, but it is not uncommon.

I don't mind using it if it works. Seems to me there's no downside to using it?

Originally Posted by scicala

#37 is the pump.overide spring. Not a return spring.
Sal

Exactly, so what is pushing the rod back up (with the plunger) after you press the accelerator?

Originally Posted by Merc Cruzer

This is from a later carb, but the concept is the same. Sometimes a picture, is better than a drawing. Hope it helps.

So, this is the first photo I've seen that shows that second spring on the main rod. But, the hole that the rod goes through seems to tight, I don't see how a spring fits in there. Or is it compressed on top/bottom of the shaft it goes through? That's what I'm confused about.

Originally Posted by jplutz

Greetings Warbird,
There is NO spring on the outside of the "Accelerating Pump Operating Rod" #9531 in the upper illustration. The "Accelerating Pump Link" # 9526 connects #9531 to the "Throttle Shaft Linkage" # 9581.
Your pictures looked familier. In my first post I asked for info about my installed carb, which comes from a '55, sans choke. (I didn't know about it)
In an old candy tin, covered in rust and dirt was the old carb, completely disassembled. I decided to put it back together. I got most of it correct, but left out the throttle rod because the throttle plates are so corroded they don't go in the slots, same with the choke plate.
So I never connected the pump link. When I saw your diagram and the photos, I went and got the carb and the link and rod were still in the bottom of the can.
Note: #9531 has a Spring Loaded Ball inside the Hole! That is why there is a Notch in the Shaft of #9526. A clip does not go in the notch
I'll try to attach photos. JP

I appreciate all the photos, but it appears I have everything you are showing there. I have the main rod, the pump/plunger, the spring for that pump/plunnger, the connecting bracket, etc. But what I don't understand is how that rod with the plunger returns, or goes back up, after the accelerator is pressed.

Originally Posted by Merc Cruzer

Note: #9531 has a Spring Loaded Ball inside the Hole!

And yes, I have the ball and clip to hold it in place!

[Merc Cruzer]

"But what I don't understand is how that rod with the plunger returns, or goes back up, after the accelerator is pressed."


It doesn't go back, up until you let off the accelerator.

First picture is with the the accelerator all the way up.

The second picture is the the accelerator partially pushed down and the pump having bottomed out .

The third picture is the accelerator pushed all the way to the floor

When you let off the accelerator, it returns to the first picture

Hope this helps.