The Stovebolt Site Forums The Shop Area Engine Shop Fuel pump install

GMC 270 engine.
Installing new fuel pump. Anything I need to do to insure pump is installed to contact cam correctly?

thanks

I use a bright light and a mirror to check that the high point of the cam is facing away from the hole in the block. That minimizes the stress on the pump housing as the bolts are tightened. DO NOT stick a finger into the hole and ask someone to tap the starter to check the lobe position!

Just before you get the bolts tightened fully, rock the pump housing up and down with the fuel lines attached until the carburetor float chamber fills.
Jerry

Wouldn't hurt to put a little assembly lube on the arm of the pump.

Failed to mention new tank and lines.
57 GMC
Any need for priming the lines, or should the new pump be able to pull from the tank no problem?

Thanks

I installed a newly rebuilt glass bowl pump on my 216 and didn't prime anything. Gravity flowed the gas to the pump and the pump did the rest.

Truck sat a couple years with old gas in it, thats why I replaced the tank, lines, and pump.
I have tried two different pumps now and cannot get fuel to pump. Both pumps appear to be an identical configuration as the old one.
I used a hand held pump to prime the lines, but the fuel pump doesn't seem to engage enough to pump. I tried it out of the truck by hand and it pumps good. Now I am doubting that I have installed it oriented correctly.
The inlet and outlet are marked and corresponding lines connected, and the arm points up.
What would cause the pump not to be actuating properly?

Thanks for any advice.

If your fuel pump(s) are brand new, they are Chinese.

I installed one last year from Carquest that wouldn't pump a single drop of fuel straight out of the box. That one was meant to replace the previous Carquest pump that lasted about 300 miles before quitting.

I finally had the "original" (actually an Airtex reman from the 1980s or 90s, I think) glass bowl pump rebuilt. It pumped gas immediately upon installation.

The first Carquest pump's arm was assembled shoddily. The three pieces of steel on the arm were misaligned and only contacted the cam on the very edge of the arm. The second one didn't do squat. The arm was probably not angled correctly or long enough or something.

Since the fuel pump arm moves in such a short arc to pump gas, it's crucial that it is manufactured correctly. I think the new ones don't "throw" far enough to contact the cam fully.

Whatever. Find an original pump on ebay and send it to Then and Now Automotive for rebuild.

The two pumps are the new ones that don't work. The shiny new pump in my hand is the one that didn't pump at all when installed.

You can see the wear pattern on the first pump that failed. Only 1/16" of the pump arm made contact with the cam due to misalignment of the components at the slave labor camp. Last pics are the rebuilt glass bowl pump which works perfectly.

Do you still have the old pump that presumably worked at some time prior to the purchase of the new pump(s)? If so, I'd contact Then and Now to see if they can rebuild it. If it's a modern Chinese pump, I wouldn't waste the effort. Find an NOS or used pump from the 1950s or 60s and send it to them.