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View Full Version : SBC Fuel pump PUSH ROD. Are there more than 1 length?



WagonCrazy
07-10-2015, 06:24 PM
Replaced a 2 year old malfunctioning (stock, cheap, chinese probably) fuel pump on my SBC today, with a new mechanical Holley 12-834 pump. 7.5 psi, 80GPH. Thats all I need for this 300 hp engine with an Edelbrock 600 carb.

Figured it was a simple swap. And it was.
Got it all back together, runs great now.

But I hear a faint knocking noise coming from down low...random at idle...kinda comes and goes...faint, but I can hear it and it WASN'T there before I did this fuel pump swapout.
Put a stethoscope to the top of the fuel pump, YEP...sounds like the pushrod is not all the way tight.

I thought a SBC fuel pump pushrod was a universal length?
Are there different lenghts? I must have one that's a hair too short?

Aargh...

Rick_L
07-10-2015, 07:23 PM
Best I know they are all the same length.

I have seen them wear. Usually the fuel pump end is cup shaped when there is wear.

Since it's a new fuel pump, suspect the pump, especially the spring under the lever arm.

WagonCrazy
07-13-2015, 01:09 PM
Problem seems to have gone away. I think it was a lack of lubrication issue when I first installed the pump. Maybe it needed a bit of engine oil to move into the base of the pump to lubricate things...Anyhow, the wagon starts as it should now, and the ticking seems to have gone away. Onto a myriad of other things on it, that always need attention....