Fuel Pump Replacement
The fuel pump fitted to the car when I purchased it was not the correct style for the 1965 high performance engine. It was a standard mechanical pump, the type you would get at any parts store. I opted to replace the pump with a new 40083-style pump (correct style for 65 350hp engine). New fittings and a new, factory-correct stainless steel pump-to-filter line were also fitted.
The 40083-style pump has a body that is screwed together (rather than being crimped like the later pumps). Original pumps are no longer available, only reproductions are available now. The Airtex pump I purchased is a good quality reproduction.
Before removing your old fuel pump, make sure you have ALL the parts you need to fit the new one. The size of the inlet and outlet fittings on the Carter and Airtex fuel pumps varies a lot — I had three fuel pumps and none of them used the same size fittings. Don't assume (as I did) that the new fuel pump will be able to use your existing fittings. I discovered this the hard way when I had already fitted the new pump only to discover I didn't have the correct outlet fitting.
Common automotive pipe fittings include AN, UNF, NPT and BSP.
- AN and UNF fittings use SAE (parallel) threads.
- NPT fittings have tapered (conical) threads and seal by an interference fit at the threads. They require a thread sealant.
- BSP fittings have straight (parallel) threads.
Also be very careful with fuel lines with flared ends. The fitting that they screw in to must be designed to accept a flared end to create a seal, otherwise when you start the engine fuel is going to squirt out all over your engine bay (ask me how I know this).
The new pump that I fitted in 2020 (a reproduction 40083-style pump) started leaking. In December 2023, SR Performance replaced the pump with another reproduction 40083-style pump. In April 2024 this pump failed and was replaced again. It was difficult to find a suitable pump, the Holley carb on the L-79 wants only around 7 pounds of fuel pressure, most of the mechanical pumps available deliver at least 14lbs. SR Performance fitted and tested three pumps before they found one that had the correct fuel pressure.
The pump fitted to the car looked like the one on the left, the housing was crimped together and the inlet used a push-on barb fitting. The correct 40083-style pump has a housing that is held together with screws and uses pipe fittings for both inlet and outlet.
The pump fitted to the car looked like the one on the left, the housing was crimped together and the inlet used a push-on barb fitting. The correct 40083-style pump has a housing that is held together with screws and uses pipe fittings for both inlet and outlet.
