Bent fuel pump rod

[duece1951]

Has anyone experienced a bent fuel pump rod? Truck has been parked and apart for months. Always started prior, ran rough the last few months and the new fuel filter never completely filled with fuel as did the old. Went and purchased a new pump and while installing it I could not push the rod up. Turned over the engine manually without the pump on and still could not move the rod. So I pulled it and it’s bent, new one on the way. A year ago it ran smooth and then began to run a little rough and acceleration was less, 5.0 not that I am breaking land speed records. Just looking for a possible cause.

 

[Edelbrock]

Wrong fuel pump? Wrong push rod?

 

[nvrenuf]

That’s a big piece of steel to bend. I too question if the pump is correct.

Also, any work done on the front of the motor? One of the bolt holes goes all the way to the push rod cavity, too long and it will lock the rod in place (which could result in a bent rod after turning the motor over).

 

[Ricko1966]

They bend easier and more often than you think. At some point in its life someone probably changed the pump using a Long bolt through the front to hold the pushrod,but over tightened it, millions of heat cycles and stresses finally killed it. Yea I know,that never happens and the fuel pump lobe on the cam never goes flat either. Let the arguing begin.

 

[duece1951]

They bend easier and more often than you think. At some point in its life someone probably changed the pump using a Ling bolt through the front to hold the pushrod,but over tightened it millions of heat cycles and stresses finally killed it. Yea I know,that never happens and the fuel pump lobe on the cam never goes flat either. Let the arguing begin.

I think someone was in there at some point. The plate had no gasket behind it. At least found the oil leak issue! Thanks for the responses! The bolt that “holds it in place to change it” was the short one so that was not the issue. Been searching on the internet and I have touched nothing prior. Was a farm truck barn find so no history beyond that. Thank you!

 

[HotWheelsBurban]

I think someone was in there at some point. The plate had no gasket behind it. At least found the oil leak issue! Thanks for the responses! The bolt that “holds it in place to change it” was the short one so that was not the issue. Been searching on the internet and I have touched nothing prior. Was a farm truck barn find so no history beyond that. Thank you!

Fuel pump on a square body era small block should be AC #40987 for two line(inlet and outlet) and #41216 for the 3 line(with vapor return line). Yes I sold a LOT of these, back in the day, to still remember the part numbers this many years later. Installed a few too, with 7 squares in the family fleet....
I have seen occasions where the cam eccentric lobe that drives the fuel pump, was in a position where it was at its furthest down point, so that reinstalling the new pump could be difficult due to the new pump having a tight spring, that is being extra compressed because of the rod position. The "long bolt" truck SHOULD keep it from sliding down too far but not always. I've heard of people busting or cracking the pump ears since they are cast aluminum, if they were cranking down on the bolts too hard, in this scenario.
Fortunately any of our trucks I changed a pump on, didn't have this happen. I think the long bolt is still in one of Dad's tool boxes....

 

[Ricko1966]

I think someone was in there at some point. The plate had no gasket behind it. At least found the oil leak issue! Thanks for the responses! The bolt that “holds it in place to change it” was the short one so that was not the issue. Been searching on the internet and I have touched nothing prior. Was a farm truck barn find so no history beyond that. Thank you!

The short one won't hold it you remove the short one put in a long one,change the pump remove the long one,put the short one back.

 

[PrairieDrifter]

Junk parts store fuel pumps ruined my cam lobe. Went through 5 or 6 of em. Most of em the arm failed in some way, 2 of em gushed fuel.

 

[ali_c20]

I rotate the engine till the rod is in as far as possible, put some grease on the pump rod so that it doesn't slip out, double check and install the new pump.
I only have blocks without the screw hole.
Make that the fuel pump lever is straight and has no play....had a fuel pump with a angled and loose lever on our 66 Impala, was a real pain to get the pump and rod out.

 

[duece1951]

Well the truck is an old farm truck and say go 20+ years in a barn in Georgia. Front of the engine has old oil and dirt all over it. Took the mounting plate off to get to the rod, no gasket. So that answers where the oil had come from. Enough years of oil and dirt roads stopped the leak. So if someone else years ago did something I have no way to know. I purchased the correct fuel pump, looks exact like what came out. So if anything it’s the rod that may have been too long. I was just shocked and all I see for an answer on the internet is the long bolt to hold it was left on and run. Well I did not even do that trick because I could not move the rod back to need to be held in place. Just wondered if someone else had an answer I had not run across. Thank you everyone for your replies and help!

 

[duece1951]

The short one won't hold it you remove the short one put in a long one,change the pump remove the long one,put the short one back.

I get the long short bolt exchange, I just was attempting to say I had not gotten that far to use that trick so no long bolt was ever used, by me. I the past from old owners no idea.