1100 accelerator pump adjustment

[Anonymous]

Does anyone have any tips on adjusting the accelerator pump on a Ford 1100 carb. I have adjusted as per the Ford manual(bending the rod until you get about 3/16 between roll pin on pump arm and the pump body), but I am still getting a slight hesitation when the throttle is depressed.

 

[CZLN6]

Howdy Dbowman:

1st chaek to verify that your accelerator pump is working by propping open the choke, peering down the throat and working the throttle lever. You should see a stream of gas being squirted down the venturi. If not, all the adjusting in the world will not alter your tune. UJnfortunately this is one of the weaknesses of the 1100s. A rebuild kit will usually fix it- for awhile.

Also, try the different pivot holes for the pivot pin before bending the rod.

Also, verify that your initial advance is at least 10 degrees BTC.

For all the tuning I've done on an 1100, I've never had to alter the bend of the rod. Oops, I said "never"! Let me rephrase, I've not yet had to bind the accelerator pump rod to achieve a tuning goal. But that's me. Please let us know how it comes out.

Adios, David

 

[63Futura]

David,
I am having a very similar sounding issue as dbowman is. However, my carb is (I think) a Holley 1940. Would you think that my issue could be traced to the same problem as his is? Also, would the accelerator pump rod be adjusted in the same manner on the H1940 as on the A1100?

Thank you.

 

[CZLN6]

Howdy Back Futura:

I m not as familiar with the H1940, but it's easy and quick to check to see if the pump is functioning, the same as I described for the 1100.

And yes, it is likely that a rebuild is in order rather than an adjustment. I don't believe that the Holley pump has a bent rod for adjustment. But, before you go bending, ask yourself these- Did it used to work good with this setting? Has anything happened to change the setting?

If you answered Yes and No, then it is obviously not the rod setting or adjustment.

The Holley 1940 is a more complex carb, but should benefit from a good cleaning and a rebuild kit.

Adios, David

 

[63Futura]

David,
Thank you for your reply. Unfortunately, I have already had my mechanic do a re-build on the carb. However, the stumble is still there. This carb has been re-built a number of times, so it may just be time to replace it.

Thank you again for your reply.

 

[mugsy]

The only good piece of information I got from Pony Carb was that they adjust their carbs so the accel pump squirts as soon as the throtle is moved. The rods can easily be bent and moved, so adjust it so it squirts when the throttle moves and see if that fixes the problem. If not, bend it back.

tanx,
Mugsy