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Can a fuel pump push rod make a knock noise?

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bigmanjbmopar

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Can a fuel pump push rod wear so much that it makes what sounds like the quoted rod knock? but still work the pump? I have a knock I'm trying to isolate and it sounds like its coming from the distributor area, not the heads or rear section or the middle but front.

any ideas?
 
This one (top) didn't make any noise, about 1/4" wear...to the point the 440 would start but then starve after awhile.
sYsylEw.jpg
 
Buy a stethoscope at the auto parts store and it may help you get closer to your problem.
 
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I had a customer with a ford big block that had a knock. He was ready to pull the engine. I used a long screwdriver against my ear and isolated the noise to the fuel pump. Pulled the pump, started it and the noise was gone. It was the pump making the knock.
 
I have the stethoscope that's why I can say it's not coming from the valve train other that one of the H beam rods themselves I can only think k of the pump rod. I just need to get off my *** and pull the pump sigh it's Sunday and I'm feeling lazy lol
 
Did you work on anything recently? I changed a timing chain once and put the slide adjusting bolt from the alternator in the harmonic balancer to hold the pulley on ( it's longer).Used one from the pulley on the alternator. Made a lot of racket. Dumb me pulled it all back apart to realize my mistake.
 
727 said:
Did you work on anything recently? I changed a timing chain once and put the slide adjusting bolt from the alternator in the harmonic balancer to hold the pulley on ( it's longer).Used one from the pulley on the alternator. Made a lot of racket. Dumb me pulled it all back apart to realize my mistake.
Click to expand...
No just replaced the carb its been annoying for awhile now, hoping its not the pump itself. it didn't seem louder when the scope was right over the fulcrum housing. could her it good on the fuel line though
 
70runner said:
This one (top) didn't make any noise, about 1/4" wear...to the point the 440 would start but then starve after awhile.
View attachment 600799
Click to expand...
Just got done with this, was starving for fuel. Replaced the pump with a Carter and the Shorty pump rod with a Comp unit. Hope the cam lives and had a slight noise from the pump area.
 
A worn down push rod could cause a knock for sure. But it could be the fuel pump itself. I had one on a 383 that the spring on the fuel pump was weak and not holding the rod tight to the cam lobe. Way better than a real rod knocking.
 
Edlebrock pump bronze tip rod comp cams decided to get another rod and check the length of the old to new then maybe run it for a sec with out the pump mounted to see if the noise is still there.
 
Must be the pump or something else, push rod was the same size as the new one, only difference was the old one had a beveled edge to it vs a flat edge on the new one. weird same part numbers on both. was a little quieter but I think it might be the edelbrock pump. just going to live with it until the pump fails
 
Is the oil lever higher than the last time you checked it or smells like gas? If the diaphragm is going bad, it can dump a lot of gas into the oil. Not saying it's going to make noise if it's bad but is just something else to check.
 
The issue was 8 failed lifters:mad: really got bad when one failed on the drivers side after a cruise and was super loud, I pulled the valve cover and found this

Then went to the passenger side and found all but 1 had failed.
 
Seems like I'm hearing alot of troubles with some of their products. I don't know if they just sell so much more odds of problems increased, or if there is quality concerns. Good luck
 
probably quality, they didn't even care either when I showed them. Next batch will not be comp cams, when I upgrade the cam i will choose isky or or something
 
bigmanjbmopar said:
The issue was 8 failed lifters:mad: really got bad when one failed on the drivers side after a cruise and was super loud, I pulled the valve cover and found this

Then went to the passenger side and found all but 1 had failed.
Click to expand...

Damm...sorry man that's a bummer. Not me personally but some friends are getting good results with Lunati's chrysler grinds and their better micro-trol lifters, just another avenue to explore. HFTs though, not roller. I've been recommended topline johnson hylift tappets by a few good mopar guys including some knowledgeable members here on the site. Hopefully your cam lobes are still ok.
 
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