Mechanical Fuel Pump Push Rod

[Ken]

So I finally got time to replace my fuel pump, that went south during the Round Up. Well, at least I thought it was the fuel pump. Simple enough swap and replace, no issues there. But the new pump also not pumping.

After confirming all the obvious... fuel lines correct... Yes, Fuel in tank... Yes, fuel getting to pump... Yes. I even filled the carb side of the fuel pump, thinking a prime would help get things started, but the installed new pump not pumping. So... went over and grabbed my old pump, gave the arm and couple of pushes and sure enough its sucking and pushing no problem.

Pulled the pump off and immediately notice the push rod was inset well into the plastic flange. Wish I would have thought about that a while back. I take a wrench and start turning the engine, making several full rotations and push rod never moves? Pulled the push rod out and the lower tip is worn flat and wide. I put the calipers on it and 92mm???? (alternator style pump rod should be 100mm).

I dig out my generator pump push rod (108mm confirmed), drop it into the hole, but it doesn't feel like its sitting down right, turn the engine and no movement?

So, I'm thinking something must be wrong with the cam that drives the rod? Tried to inspect it with a mirror and flash light, but can't see pshaw.
Has anyone experienced anything his and can offer any suggestions?
I know I can just replace the mech with a electric, but I would really like to understand what is wrong here, instead of just ignoring it.

Any help, comment or suggestions, would be greatly appreciated.

[Bryan Porter]

What you don't want to call me anymore???

[Ken]

Trying not to use up all my "get out of trouble" cards and I thought I would give everyone else a turn.
I was going to call you this evening.

[staggerwing]

Hey Ken:
Has this problem been remedied? I read something somewhere where the rod can actually get stuck in the plastic flange?

[Ken]

After some education from Mr Porter, I was able to determined the rod has been beat to the point it was no longer long enough to engage the fuel pump. In fact my fuel pump is fine. I took a generator rod and cut it down to about 100mm, applied a little grease, dropped it into the flange, installed my original pump and she's pumping.

I screwed up something in the ignition system messing with the fuel pump, but I haven't had time to check this out yet. I hope and think it is just a timing issue.

I'm not sure why the rod got so beat up. The rod and pump have something like ~15k miles. Not sure if there's an underlying problem. Any thought? If there are, I hope it just means replacing the rod every 10k-15k miles. Guess we'll see.

See how the top rod point, is the beaten flat.

[Ken]

Well finally got some buggy time and got Crazy Alice back on the road. I cut a long push rod down and put her back together with my original fuel pump and she's running great so far.

I wish I knew why the rod got beat to hell, but as long as she's running.

Now let's go ride!

[staggerwing]

Maybe it was just a soft rod? Was Bryan messin around behind your car for more than a minute??

[Ken]

Maybe it was just a soft rod?

that just sound too personal to get into. Is there an additive for this?

[staggerwing]

Where's Lloyd when you need him? Maybe he would know! You DO have his email, don't you? Oh, by the way, nice job on the technical presentation! No, really!

Cheers

[Ken]

You DO have his email, don't you?

Hell NO! I wouldn't have even remembered his name if you hadn't mentioned it. But if he didn't know what happened, I bet he knows someone in Kerrville that does. And he's probably already called them.