Soft fuel pump cam lobe 350 Goodwrench engine should I worry about ...

[mtnmankev]

Running a 350 Goodwrench engine in my 83 C-20 (came with the truck ).
The fuel pump pushrod ticks when the engine is running, and I know the pump is good as I installed a new fuel pump.
My diagnosis is the cam has a soft fuel pump pushrod lobe, causing the wear and noise.
My question is, should I be seriously worried about the rest of the cam lobes ?

 

[1987 GMC Jimmy]

Do you know that this is somehow affiliated with the push rod for a fact? The only sure way I would think this could be diagnosed is to run a little electric pump and see if the noise is completely gone. Are you sure it’s not something else like a lifter tick? Good oil pressure? If there was a rounded off cam lobe/fuel pump eccentric, the carb would either be getting insufficient fuel and not running right and/or your valves wouldn’t be opening like they should, and it would have a misfire on a cylinder or maybe some bogging down on a cylinder when it can’t expel its combustion byproducts. The only soft factor as far as a cam goes is that most oil today doesn’t have as much ZDDP as back in the day so people run higher ZDDP brands or use additives to compensate and preserve their lobes from premature wiping. I’d dig into the tick more, but if you’re not having actual symptoms, I’d say that you valves and pump are operating alright for the time being.

 

[mtnmankev]

The engine runs good and strong and I don't detect any lifter noise from the valley.
The factory dropped the ball on this engine and did not finish the threaded hole to put a bolt in to hold the fuel pump rod, it's a blind hole.
First time I have ever seen that on a SB Chevy engine.
Sorta makes me wonder where else they dropped the ball ............

 

[1987 GMC Jimmy]

Hmm, I don’t know if that’s deliberate or their fault. If they made it that way, maybe it was so engines that utilized the hole for whatever reason could have it and it not go all the way through to where the rod lives. That way, for engine’s that had no use for it, it wouldn’t have to be plugged. That’s just a guess, though. It’s tapped, though, right? There are several things you could/should do. Make sure the valve lash is set correctly, make sure the oil pressure’s acceptable, and even do a ZDDP additive if it’ll make you feel better. I don’t, but maybe I should...

 

[mtnmankev]

The blind hole is threaded and has a short 3/8-16 bolt in it, and nothing else uses that hole/bolt in this application.
I am tempted to drill it out and install a helicoil so i have the option of using the hole as originally designed,
It was a royal PITA to replace the fuel pump without the use of the hole, as the rod slides down and the pump won't go in (as I am sure we all are painfully aware of).
Doesn't help working in the engine compartment at the weird angle needed, with my back screaming the whole time.
May just install a blockoff plate and go with electric pump, as I know my oil will never be contaminated with gas if the diaphragm fails and fills the crankcase with gasoline (and I have seen it happen in my years of working on cars).
As long as the engine continues to run as strong as it does, and it LOVES to cruise 85+ on the highway with nary a hiccup, I probably won't worry much about the cam lobes operating the valves.
Just wanted to ask and get some feedback about that rod making noise when I have never encountered it on any other engines and have heard rumors of soft cams in some Chevy engines.

 

[HotRodPC]

If it's running good and you're 100% certain it's just the fuel pump rod, then I'd go E pump, rod removal and block off plate. My biggest concern right now would be the metal shavings running around in the oil from pump lobe. I'd imagine they're ever so so fine, but I'd make sure I'm running a quality filter for now and maybe an oil change just to be on the safe side. I think I'd be running an expensive Mobil 1 or K&N filter with a clean oil change.

 

[bucket]

You put grease or vaseline on the fuel pump rod before you slide it in the block. It will hold it in while you install the plate and pump.

 

[1987 GMC Jimmy]

I’ve used a hacksaw blade and my finger (somehow). I think grease really is the best way, though.

 

[74 Shortbed]

That's how you do it on a big block..