2 fuel pumps or 1 ???

[Northern Jewel]

I have a 1971 80hp Merc shorty that has only one fuel pump, the motor seems to run good but I picked up a 1970 80hp parts motor
just in case. When I was looking at the 1970 I noticed that it had two fuel pumps which seem to be a little smaller than the single pump on the 71. Was there a reason for this? Would I be better off rebuilding the 1970 with 2 pumps or running the 71 with one pump. Other than the fuel pump differance and the coil being larger on the 1970. All other parts seem to be the same. Any thoughts would be appreciated.

[ken medendorp]

I would install a fuel pressure gauge. Should have about 4psi at all times with running carb's. I run one pump in my drag.

[Raceman]

On that 4 cyl inline you'll never know the difference between the fuel pump designs. I'd run whichever setup is easier. Merc changed all the older engines which had 2 pumps to singles over the years. Even the old 1500's, being the top production inline had the single pump.

Ken's obviously talking about electic pumps. A pressure guage isn't necessary with the engine mounted pumps unless it's for diagnosing a problem.

[Northern Jewel]

Dragonwolfe and I were thinking that Merc was trying to cut cost while slowly phasing out Kiekhaefer. We were comparing the front face plates on the motors and on the 70 it has KIEKHAEFER
in big bold letters over Mercury in small
letters, on the 71 Kiekhaefer is small over a big MERCURY emblem. Pretty sad.:(

[Raceman]

Carl actually sold Mercury to Brunswick long before that time. I believe in 1961, although he remained around for a while.

[Northern Jewel]

Originally posted by Northern Jewel
Dragonwolfe and I were thinking that Merc was trying to cut cost while slowly phasing out Kiekhaefer. We were comparing the front face plates on the motors and on the 70 it has KIEKHAEFER
in big bold letters over Mercury in small
letters, on the 71 Kiekhaefer is small over a big MERCURY emblem. Pretty sad.:(