Mechanical Fuel Pumps. Whatcha Got?

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The new one I put on in 2017 was a cheapo Delphi, DE MF0007 from Rock Auto for 15 bucks. Made in China of course, but it works fine. I run a 3/8 line to my Holley SA670 carb (4150) and have regularly revved the old girl to 5K + without any fuel starvation issues.

 
Mechanical or electric?

Current mechanicals are limited to stock replacement, RobbMc race pumps, or the offshore sourced pump sold by Speedmaster, RPC and any other random seller name that buys them at wholesale. I have no experience with them, but my distrust level is fairly high. If you're lucky, you might find a new old stock Holley or Mallory pump. 

If you're going electric, that gets murky, as there are so many out there. Holley seems to have gone all China made parts, and their pumps are no exception. A friend replaced his 20 yr old Holley HP pump and the new one lasted one entire day or cruising. summit took care of him and he replaced it with an Aeromotive SS unit, and so far, so good. 

 
Mechanical or electric?

Current mechanicals are limited to stock replacement, RobbMc race pumps, or the offshore sourced pump sold by Speedmaster, RPC and any other random seller name that buys them at wholesale. I have no experience with them, but my distrust level is fairly high. If you're lucky, you might find a new old stock Holley or Mallory pump. 

If you're going electric, that gets murky, as there are so many out there. Holley seems to have gone all China made parts, and their pumps are no exception. A friend replaced his 20 yr old Holley HP pump and the new one lasted one entire day or cruising. summit took care of him and he replaced it with an Aeromotive SS unit, and so far, so good. 
Mechanical. 

 
Funny, that post was by Fast E, who used to own Big Red's car... 
Right??? I'm not having the leaking issue he was, unless it's internal. Just very inconsistent fuel pressure even with a Summit regulator. I have had fuel in the oil, but always assumed that was from washing down the cylinders. Maybe not. 

 
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The new one I put on in 2017 was a cheapo Delphi, DE MF0007 from Rock Auto for 15 bucks. Made in China of course, but it works fine. I run a 3/8 line to my Holley SA670 carb (4150) and have regularly revved the old girl to 5K + without any fuel starvation issues.
I went ahead and ordered this Delphi unit from Rock Auto as well. I didn't see where anything else was worthy of extra $ or wait. Thanks!!

 
I went ahead and ordered this Delphi unit from Rock Auto as well. I didn't see where anything else was worthy of extra $ or wait. Thanks!!
Like I said, I've had no problems with that one, but next time I order from R/A, I'll order a spare...... just in case.

 
"A fuel pump with a defective diaphragm may be torn or have developed holes from wear. These tears or holes allow fuel to escape past the diaphragm and exit the fuel pump housing. A leaking fuel pump can be noticed as fuel droplets or puddles on the ground and a strong smell of gasoline when the car is running."

Boy, that sentence in red jumps right out. Anyone that knows my "Timing Frustrations" thread knows that I've been chasing this from day 1 of brining the car home. Also the lack of being able to dial in a carb (your pick of 3 different ones now) and keep it dialed in. 

 
"A fuel pump with a defective diaphragm may be torn or have developed holes from wear. These tears or holes allow fuel to escape past the diaphragm and exit the fuel pump housing. A leaking fuel pump can be noticed as fuel droplets or puddles on the ground and a strong smell of gasoline when the car is running."oy, that sentence in red jumps right out. Anyone that knows my "Timing Frustrations" thread knows that I've been chasing this from day 1 of brining the car home. Also the lack of being able to dial in a carb (your pick of 3 different ones now) and keep it dialed in. 
................... then don't run it!!!

Find the problem. An external leak can't be that hard to find and fix. Can a fuel pump leak back into the crankcase? 

 
Kinda funny but a few days after I read this post my fuel pump started leaking. I started my car yesterday and backed it out of the garage to let it warm up a bit. Went back in to turn the lights off and then I noticed that I had a pretty good leak coming from under the front engine area. Thought at first it might be radiator fluid cause I recently changed the thermostat. So I got under the car with the engine still running and I saw it coming from the fuel pump. Definitely gas, not rad fluid and I was even able to see it seeping from the fuel pump housing. 
So I just ordered a Carter from Rockauto. Nothing fancy, it was 16 bucks and I hope it works like it’s supposed to.

 
................... then don't run it!!!

Find the problem. An external leak can't be that hard to find and fix. Can a fuel pump leak back into the crankcase? 
They can. Although the external leak is far more common. But like I said, I don't have an external leak. I do have fuel in the oil and super inconsistent fuel pressure though. Could be a bad diaphram, but they way it's on and off, I'm actually wondering if it might not be the springs on the arm. I'll find out once I pull it. 

 
Kinda funny but a few days after I read this post my fuel pump started leaking. I started my car yesterday and backed it out of the garage to let it warm up a bit. Went back in to turn the lights off and then I noticed that I had a pretty good leak coming from under the front engine area. Thought at first it might be radiator fluid cause I recently changed the thermostat. So I got under the car with the engine still running and I saw it coming from the fuel pump. Definitely gas, not rad fluid and I was even able to see it seeping from the fuel pump housing. 
So I just ordered a Carter from Rockauto. Nothing fancy, it was 16 bucks and I hope it works like it’s supposed to.
That's some crazy timing right there. Good thing your leak was external and you noticed it right away though. Since we have a Carter and Delphi both going in from Rock Auto at the same time, we'll have to remember this post and see which one lives longer. LOL

 
That's some crazy timing right there. Good thing your leak was external and you noticed it right away though. Since we have a Carter and Delphi both going in from Rock Auto at the same time, we'll have to remember this post and see which one lives longer. LOL
 Well so far my Delphi is 3 summers old and no leaks................ yet!

 
Ya that’s why I got the Carter since Stanglover already had a Delphi. We’ll have to see.
I don’t know what fuel pump is on my car that failed. It was new when I got the car, so it’s probably from 2013 or so.

 
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