1965 corvette fuel pump problems

I have a 1965 corvette 327-365hp engine, and have fuel pump problems. This is the third one I put in over a period of ten years most recently two in the past year. All three had broken fuel pump arm springs. Could anybody out here tell me what is causing this problem. Tolly

I'm not much help, but I love the car!! Ask robbyf he might know. I need to learn about the Muscle cars for next month anyway!! YAY!!





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martian leader

Thanks martian leader for the feedback.

Tolly --
If the springs are breaking,... that is due to a fatigue-failure.
The fatigue-failure could be due to repeated excessive force being applied, or.....cyclic fatigue. Since you've replaced two pumps recently, I'd rule out the cylic fatigue for now.

Go back to the excessive force idea.... Is there any way you have to change the amount of force being applied? That would normally be by changing a pivot-point on an arm, or moving the mount-location. Sorry, I don't have a picture in front of me, or I might have some other ideas.

That Martian Leader is quite a girl!

thanks to you both.


* Smirking and laughing*


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martian leader

Pour quoi, mam'selle?

There could be a whole list of causes of that particular problem. Has the engine been rebuilt? If so, how many times and have the main bores been line-honed or resized? What that basically means is that the main caps are machined slightly and the mains are then re-bored. What this does (aside from resizing and straightening the main bore) is makes the crankshaft centerline incrementally closer to the camshaft. Since the mechanical fuel pump is driven by an eccentric lobe on the camshaft, this could increase the leverage on the fuel pump arm. It's a long shot, but anything is possible when it comes to old cars. Another thing that COULD have happened is that you could very well have bought three defective pumps. Try a different brand or maybe an aftermarket part that may be more expensive. It does happen. I know a tech who had to replace 4 BRAND NEW PCMs because each one was defective. I would focus on the connection between the pump and the camshaft though. It sounds like something is putting excess leverage on the arm.