Fuel Pump - 1940 Deluxe 8

[ragtop40]

It appears the fuel pump on my 1940 Deluxe 8 has failed. I can purchase a rebuilt pump, or a kit to rebuild mine. Does anyone have any experience in rebuilding the dual vacuum/fuel pump?

[Larry]

In reviewing the procedures in the 1940 Shop Manual, it appears there are a couple "tricky" areas to deal with, but not too difficult that the average guy can't get through it. I do not have the 1940 Shop Manual up in our On-Line Shop Manual Reference Library yet (will one day!), but if you like I will gladly scan and sent you the pages with the rebuilding procedures.

One important item if you decide to rebuild yourself is to be certain you get a new kit... not an NOS one, but brand new, manufactyred with material compatibly with today's aggressive fuels.

Check with one of our Featured Commercial Suppliers "Then and Now Automotive" listed under "AFFILIATES" then "Member Discounts" and "Parts." They carry all that you wil need and also offer rebuilding services. Be sure to tell them that you are a PontiacRegistry.com member and they will give you a discount.

Please let us know how you do with this.

[ragtop40]

I had my dual vacuum/fuel pump rebuilt and am ready to re-install. The pump has four (4) fittings...fuel line from tank, line to carb, and vacuum line to windshield wipers. The 4th is at the top (the vacuum pump) and I do not know what to do with this fitting. Should there be another line to it, or should it be capped off?
Thanks

[Larry]

My first answer to blurt out was .... "well, of course that goes to the intake manifold."

Then, perhaps it is from age, and numerous boot marks in the teeth from experience, that I said "right?"

So I started scouting around, to prove my response before sending you a bum answer. Good news! I was right. Check the diagram below from an old Pontiac Service Craftsman Training booklet. It is just one portion of a fuel pump operation section, but it clearly shows the hookups at the top. A double check of the 1940 Service Manual confirms.

What's kind of intersting is that the intake hookup for the dual-action pump isn't really the suction source for the wipers (as with the single action pump), but more of the exhaust route for the air pressure created by the pumping movements.

Please keep us posted on your progress.