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Re: Carter 4070 electric fuel pump plumbing [message #261558 is a reply to message #261552] Thu, 11 September 2014 03:00 Go to previous messageGo to previous message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma:
Senior Member
roy1 wrote on Thu, 11 September 2014 00:45
Were any of them carter 4070's ? My wife's 32 ford had a 4070 in it for more then 30 years and it was an every day driver. The electric pumps that I had problems with were diafram pumps rather then gear drive except for a holly pump.



The mechanical pumps were all diaphragm. One Carter 4070 on the motor home the other was One of those things Jim B. is selling. I do not think it was a diaphragm type pump. These were no big deal since I had a mechanical pump to back them up. That was the first one, and it was installed on my motorhome by a PO. Every other electric pump was an in tank OEM pump mostly Ford and GM. Those are the ones that I carry a spare for in each car. I understand these fail most often when you let the tank get too low on fuel. They use the tank fuel for cooling. They are rotary and lock up. I have been successful temporarily by wacking the bottom of the tank to get them started again. Once you get them started do not turnoff the car until you get to the place where you are going to change them. Sometime you can successfully wack them again and sometimes not.

I just remembered a few more. They were all electrical interrupter types used on aircraft just like the Onan ones. I have never replaced a mechanical one on an airplane. Usually the airplane electric interrupter type we take them apart, and just clean them thoroughly. Then they are usually good to go again. Again they are backed up by a mechanical pump so when they fail it is no big deal. The mechanical type is actually the main pump and the electric is the back one.

The pre-startup check list has you turn on the electric pump and read the fuel pressure. Then turn it off, start the engine, and read the fuel pressure from the mechanical one. On on initial taxi and run-up prior to take off, you do it on mechanical only. Just prior to take off you turn on the electric one again and take off on both. Once you are at a safe altitude (usually cruise altitude), you turn off the electric and leave the electric off until starting to land. You do not want an engine failure on either take off or landing.

I have had three minor ones. One carb icing at about 3000, One dry tank on landing, and one vapor lock at 4000 feet. You get very busy, very quickly trying to figure out and recover from the failure.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Updated on: Thu, 11 September 2014 04:17]

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