The mechanical fuel pump in my 56 Nomad failed in late April. The diaphragm had ruptured. It just so happened that I was at Mikey's shop when the failure was noticed. So, I ordered a new fuel pump from one of our trusted vendors. I left my Nomad at his shop where it waited for the new fuel pump. When the fuel pump arrived, it looked fine, just like an OEM 4460 fuel pump, but without the AC logo. Mikey and I installed the new fuel pump, and I drove it home. I was so happy with the new pump, that I ordered another new pump from the same source, so that I could have a ready spare. After a couple of days, I noticed that the car started surging as if it was running out of gas. The car ran fine until speeds were above 35 MPH. When the second pump arrived, I swapped it out with new pump that Mikey and I had just installed. The second fuel pump had exactly the same failure symptoms at speeds above 35 MPH.
I couldn't have gotten two bad fuel pumps could I? I could see bubbles in my glass filter bowl that increased with engine RPM. So, however unlikely it was that I had two new fuel pumps that were bad, I advertised here on Tri-Five for a NOS 4460 AC fuel pump. A member here responded to the ad, and 10 days later the NOS pump arrived. I had also ordered a rebuild kit for the NOS pump that was compatible with ethanol fuels.
While this was going on, I read a concurrent thread here about a 265 engine randomly stumbling and the owners efforts to troubleshoot it. After much troubleshooting, he traced the problem to two different bad mechanical fuel pumps that he had purchased while troubleshooting the problem. This sounded just like my problem, so I was encouraged that someone else had experienced similar failures with two recently purchased fuel pumps.
When I had the NOS AC fuel pump and the rebuild kit in hand, I limped my Nomad back up to Mikey's shop at 35 MPH for the NOS pumps rebuild and installation. When the rebuilt NOS AC fuel pump was installed, all of my fuel problems were corrected.
The moral of this story is that just because a part is new, that doesn't mean that it is a good functional part. A large majority of the fuel pumps currently being produced are made in China, and probably in the same plant, regardless of branding. These pumps are very suspect. So don't fall for the "it couldn't be a bad new fuel pump" because as I said before, just because it is new does not mean that it works!
The vendor that supplied me with the two failed pumps has agreed to refund my money. But, I have had over a month of uncertainty and aggravation because of two worthless Chinese knockoff pumps that look good, but work like crap! And, a precious month of the short cruising season here in Wisconsin has been wasted with a non-reliable car.
I highly recommend that anyone needing a replacement mechanical fuel pump, buy an original NOS or used AC branded pump. Even if used, they can be easily restored with an ethanol tolerant rebuild kit. Here is a link to the rebuild kit that I used.
P.S. I have also purchased another original AC 4460 fuel pump, and it too has now had a new rebuild kit installed. This pump is my ready spare, just in case I need it in the future.
Steve
I couldn't have gotten two bad fuel pumps could I? I could see bubbles in my glass filter bowl that increased with engine RPM. So, however unlikely it was that I had two new fuel pumps that were bad, I advertised here on Tri-Five for a NOS 4460 AC fuel pump. A member here responded to the ad, and 10 days later the NOS pump arrived. I had also ordered a rebuild kit for the NOS pump that was compatible with ethanol fuels.
While this was going on, I read a concurrent thread here about a 265 engine randomly stumbling and the owners efforts to troubleshoot it. After much troubleshooting, he traced the problem to two different bad mechanical fuel pumps that he had purchased while troubleshooting the problem. This sounded just like my problem, so I was encouraged that someone else had experienced similar failures with two recently purchased fuel pumps.
When I had the NOS AC fuel pump and the rebuild kit in hand, I limped my Nomad back up to Mikey's shop at 35 MPH for the NOS pumps rebuild and installation. When the rebuilt NOS AC fuel pump was installed, all of my fuel problems were corrected.
The moral of this story is that just because a part is new, that doesn't mean that it is a good functional part. A large majority of the fuel pumps currently being produced are made in China, and probably in the same plant, regardless of branding. These pumps are very suspect. So don't fall for the "it couldn't be a bad new fuel pump" because as I said before, just because it is new does not mean that it works!
The vendor that supplied me with the two failed pumps has agreed to refund my money. But, I have had over a month of uncertainty and aggravation because of two worthless Chinese knockoff pumps that look good, but work like crap! And, a precious month of the short cruising season here in Wisconsin has been wasted with a non-reliable car.
I highly recommend that anyone needing a replacement mechanical fuel pump, buy an original NOS or used AC branded pump. Even if used, they can be easily restored with an ethanol tolerant rebuild kit. Here is a link to the rebuild kit that I used.

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P.S. I have also purchased another original AC 4460 fuel pump, and it too has now had a new rebuild kit installed. This pump is my ready spare, just in case I need it in the future.
Steve