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Post Info TOPIC: How common is this Holley accelerator pump issue?
jim larson


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How common is this Holley accelerator pump issue?
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I rebuilt my carb last winter due to some gas leaks around the accelerator pump.  Two accelerator pump later, I am having the same issue.

When the car sits for a few days, gas leaks down a bit and puddles on the intake.  I thought that was the only issue; but will checking things today, with the wife in the car and coil wire disconnected, she turned the starter and there was no visible leak.  But as soon as she pumped the accelerator there was visible leakage.

I trued the surfaces of the fuel bowl and pump on the rebuild and had to add a washer to the asserator pump screws to keep them from bottoming out.

I am thinking it could be leaking from the gasket to the pump or bowl  or where the rivet attaches to gasket.  Am I making a logical conclusion.  Is there anything to do when I replace the current accelerator pump to help with these issues?  Thanks,

 

 



-- Edited by jim larson on Tuesday 2nd of June 2015 02:49:03 PM

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Jim L

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Seems you may have a leak at a gasket or o-ring that connects the discharge holes thru the metering block to the main body.

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Mitch D.   River Falls, WI

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jim larson


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Lost in the 60s wrote:

Seems you may have a leak at a gasket or o-ring that connects the discharge holes thru the metering block to the main body.

 The gas appeared to come out right at where the arm of tha pump pushes up.  Not sure what you mean by an "O". Ring that connects the discharge holes.  I never noticed one in there.cuckoo



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Jim L

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jim larson wrote:
Lost in the 60s wrote:

Seems you may have a leak at a gasket or o-ring that connects the discharge holes thru the metering block to the main body.

 The gas appeared to come out right at where the arm of tha pump pushes up.  Not sure what you mean by an "O". Ring that connects the discharge holes.  I never noticed one in there.cuckoo

 It may not have an o-ring. I just mentioned it as a means of sealing between the parts. It's probably part of the gasket.

It sounds like the diaphragms are getting ruptured. Is the arm bent or adjusted too tight at the screw  and over extending the diaphragm ??

Only other explanation would be a leaking seam on one side of the diaphragm and a housing...dunno



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Mitch D.   River Falls, WI

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John D


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Quick Tip:

Put a light smear of Vaseline on the rim of the diaphragm around the screw holes, and on the screws. They have a habit of grabbing on the thin rubber, pulling it in and tearing.

As Mitch suggested... the total throw of the linkage at the diaphragm is about 3/16" max. Usually less. Sounds like you're pressing it in too far and ripping it.

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John D. - St. Louis Park, MN.

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jim larson


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I resurfaced the housing some more.  Now the two surfaces are  flush. Then to compensate for the removal of some of the diaphram surface and some of the fuel bowl surface I shortened the screws about 1/16th of an inched to keep the screws from bottoming out. Then I put in a new pump with the alcohol gasket.

Good news, no leaksnana

Arm  of pump set so there is .015 clearance from bottoming out.



-- Edited by jim larson on Wednesday 3rd of June 2015 06:22:47 PM



-- Edited by jim larson on Wednesday 3rd of June 2015 06:25:50 PM



-- Edited by jim larson on Wednesday 3rd of June 2015 06:27:36 PM

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Jim L

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Good deal. Let's hope is stays NO LEAKS...thumbsup



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Mitch D.   River Falls, WI

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Knew you could do it!

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Kevin

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