1964 Johnson 75 HP electra shift running rich?

[807johno]

Hi, I have a 1964 Johnson 75hp electra shift. Whenever it is running it seems like it puts ALLOT of fuel into the water, it also seems to burn through a tank of gas really fast, even when I have it throttled back. Whenever I have the power to it, it seems like sometimes it is running fine, and other times it is a bit more sluggish, but will surge for a few seconds every once and awhile and I'll gain a few miles per hour. Just wondering if this sounds like fuel problem like running way to rich for some reason, or something else like an electrical problem. I did replace the coil this year and it is running alot better, but it is still burning allot of gas. Any advice is greatly appreciated.

Thanks

 

[F_R]

Re: 1964 Johnson 75 HP electra shift running rich?

They do burn a lot of gas, just the nature of the beast. Up to 6 or more gallons per hour depending on speed. At idle, they actually waste nearly as much gas as they burn. I can't tell from here if it is running too rich or not. But it "shouldn't" be. It has a fixed high speed jet, and you can adjust the slow speed needles.

Things that might make it run rich:

1. Somebody messed with the high speed jets. Jammed wires and stuff through it, including drill bits??

2. A ruptured fuel pump diaphragm.

4. Slow speed jets set too rich. Turn it to the right till it loses power or coughs (at idle), then back to the left till it recovers.

 

[807johno]

Re: 1964 Johnson 75 HP electra shift running rich?

Thanks for the advice, I did have the boat idling for quite awhile to let it warm up, so that would explain alot of the gas waste. I'll take the fuel pump apart next weekend and see if there is anything that looks wrong with it. Thanks again

 

[807johno]

Re: 1964 Johnson 75 HP electra shift running rich?

I checked all the fuel pump parts and they seem fine. I also adjusted the low speed jets and for the most part it idles alot better as well. When ever I'm driving it though, sometimes it runs awesome, and other times it is really sluggish of the start and the motor surges allot. When this is happening even when it is up to speed it seems like there is a bit of hesitation, and sometimes there will be significant power changes almost as if someone is moving the throttle back and forth when im not touching it. Just this evening when i was putting it back on the trailer it was idling kinda rough, and then, when it was still in neutral all of a sudden it would rev up pretty high and then die. After that it was working fine again. The whole thing seems pretty random, some time it runs awesome and sometimes it doesn't with out changing anything. I'm pretty sure it is a fuel problem of some sorts, and advice would be greatly appreciated.