Another worn fuel pump pushrod question

[machelis]

Howdy folks,

Just had my first fuel pump pushrod wear out on me. It's oem from the 400 that is now a 451. Lost about .125" and it ruined my drive home.

I don't have a carter that a lot of folks on here seem to have issues with, but I have an edelbrock 12-440-11 pump. Is it possible to snip a coil or two off the return spring to lower the pressure on the rod? Or is there another spring I can swap in? I have two more oem rods, but this first one wore out in only 1560 miles. I'd love a reliable cruiser, so an electric pump is off the table, and the idea of metal floating around in there worries me.

The rod end towards the Howards cam looks pretty rough. Is it possible the cam lobe is wearing out? I can't afford a new cam and was hoping to double the miles on the car this year. Not sure what my best route is to get back on the road.

Any and all advice will be appreciated.

Thanks

 

[Mackman]

I wore one out in about the same number of miles, replaced it with a hardened pushrod from Hughes Engines. So far so good.

 

[gary h]

I wore one out in about the same number of miles, replaced it with a hardened pushrod from Hughes Engines. So far so good.

About how many miles are we talking on the Hardened Hughes pushrod ?

 

[RemCharger]

So you used a stock rod on a billet roller howards cam?

 

[machelis]

So you used a stock rod on a billet roller howards cam?

Is this a no-no? I had the engine built, so I never read any instructions or did any research on the installation of specific push rods for Howards cams.

 

[DanielSlocum]

had that problem twice over the years. both times the engine was not hurt,nor was the camshaft.
definetly change the oil and filter. get a hardened pushrod and should be good.
too bad they dont give any warning with the h.v. pumps.
with any near stock engine....the h.v. pump isnt necessary.
good luck.

 

[Mackman]

About how many miles are we talking on the Hardened Hughes pushrod ?

3500 so far.

 

[69hemibeep]

Are you running a high zinc phosphate oil? The pushrod is basically a non roller lifter it needs it.

 

[machelis]

Mackman, have you taken the pushrod out and checked for wear and length? I'd be curious to see wear and tear after 3500 miles.

I run rotella t4 with zinc additive. I'll order up a hardened push rod from hughes.

Thanks guys.

 

[khryslerkid]

The 12-440-11 Eldebrock and Holley is the same pump as the M6903 Carter just chrome plated. Eldebrock supposedly ordered them from Carter with the pressure in mind for the Eldebrock carburetors to be less than the M6903. One way to tell how strong the spring might be is to check your fuel pressure. If it's higher than it should be more than likely it has a strong spring. The heavy spring rate is what is contributing to push rod wear. The other thing is there's lots of inferior aftermarket push rods out there. Howard's has come up many times for premature wear.

Read this thread for some details...

Mechanical Fuel Pump 101

 

[threewood]

It'd be nice if someone could come up with one that used a roller on the cam side and something to keep it from rotating.

 

[eldubb440]

It'd be nice if someone could come up with one that used a roller on the cam side and something to keep it from rotating.

tree'd....... I was going to suggest someone develop a roller tip push rod

 

[69Bee]

Mackman, have you taken the pushrod out and checked for wear and length? I'd be curious to see wear and tear after 3500 miles.

I run rotella t4 with zinc additive. I'll order up a hardened push rod from hughes.

Thanks guys.

The first problem is if your cam is a billet as someone mentioned above, you MUST use a fuel pump rod with a bronze tip which goes towards the cam.
The second problem is you are using the wrong oil. You are using a diesel oil with a zinc additive. Dump the oil and replace with the proper high zinc oil such as Joe Gibbs Driven or Amsoil. Those high zinc oils already have the proper amount of zinc already Pre-blended in. There is no need to add zinc additive to a regular oil when a correct pre-blended oil is available. As far as the diesel oil goes, you should not use an oil designed to be used in a diesel engine. It has tons of detergents and other things for diesel engine as they are very dirty due to the fuel. You should be using the proper SAE spec oils designed for gas engines, and also use the proper oil that your cam is designed to use. I would recommend a "Full" synthetic if you are running a roller cam, and one of the "High" zinc oils available from Joe Gibbs Driven or Amsoil if you are using a flat tappet cam. Also, Joe Gibbs Synthetic has zin in it also, but is quite expensive.

 

[Cranky]

It'd be nice if someone could come up with one that used a roller on the cam side and something to keep it from rotating.

Just can't see how that could be done......after all, there isn't that much pressure on the shaft for someone to engineer a roller for that application.

And after researching diesel oil in an automotive engine, I agree with what was mentioned about using it even after using it for well over 30 years in gas engines....may be ok in a street driven vehicle that doesn't see high rpm but certainly not for a performance engine that sees high rpm. Diesel oil isn't formulated for high rpm and will foam at high rpm's.

 

[threewood]

The first problem is if your cam is a billet as someone mentioned above, you MUST use a fuel pump rod with a bronze tip which goes towards the cam.

Can you explain this to me?

 

[machelis]

I'm also curious as to how a bronze tipped push rod will last longer then a hardened one.

As for the oil, once again I'm using what my engine builder recommended. I did however use "driven" oil for my break-in. I'll find some more of the good stuff from now on.

Always learning on this forum.

 

[Cranky]

I'm also curious as to how a bronze tipped push rod will last longer then a hardened one.



Always learning on this forum.

It depends on what the cam is made from.....billet steel vs cast iron. Both require different types of materials to 'rub' on them.

 

[69Bee]

As Cranky said, a Billet steel cam requires a brass tipped pushrod, while a flat tappet cam uses a regular/hardened pushrod. Same reason you need to go to a brass oil pump drive on a billet cam

 

[Orig69]

You could possibly find the correct fuel pump pushrod in the mechanical parts section.

 

[machelis]

I've read a few people having worse experiences with the howards 92152 fuel pump push rod.