Cam in low position?.

[Alwaysreadyrob]

Is it possible with a high mile engine that the cam lobe the mechanical fuel pump works off of can be so worn even a new mechanical fuel pump wont perform to its fullest potential?

 

[Thewespaul]

Yes, the more wear the less throw the plunger in the lift pump will have, so each stroke displaces less fluid. I’ve never seen the lobe completely wiped out where it wouldn’t pump like you sometimes see on small blocks.

 

[notenuftime]

Going to put the pump in tomorrow fighting the weather. Had to replace the steel line running from pump to filter due to bad threads. Going to get 1/4 npt pressure fit fittings for both ends then run a rubber line.
Always something more to a job.

 

[icanfixall]

The cam lobe for the lift pump must be facing up so you have less pressure on the lift pump arm. It makes it easier to install. And... The cam eccentric is cast iron.. Not aluminum. In the end of all this you MUST have the arm UNDER the cam. If the arm is on top of the cam it breaks off. One member found three broken arms in his oil pan when he rebuilt his engine.

 

[IDIBRONCO]

The cam eccentric is cast iron.. Not aluminum.

I have never checked. I just assumed from the color that it's aluminum. Another reason to have the lobe in the "up" position is that it's harder to get the arm over the top of it when it's like this.

 

[Oledirtypearl86]

@icanfixall is right love up because the arm of the pump goes under the cam and I installed studs that are long enough to get the arm under the lobe and still have a few threads hanging out to start the nut and washers