1957 7.5 evinrude with no power

[ebauman]

Hello all. I have a 1957 7.5 hp evinrude on a 14' aluminum boat. It starts and runs well . In neutral it will rev up nicely but put it in gear it will hardly rev past idle. I have adjusted the low idle and fast idle with no change. Not bad for trolling but kind of slow other wise. Oh and this is with only one person in the boat. Any help or suggestions would be appreciated
Eric

 

[Sea18Horse]

Re: 1957 7.5 evinrude with no power

Well I'd say the first thing to check is if it's running on both cylinders. It sounds like it might be running on only one. You may need a helper for these checks. Although you may be able to do it in a test tank. When it is acting up pull off one spark plug wire at a time. See if it makes no change when you pull one and dies when you pull the other. If you find it is running on both get yourself a spray bottle filled with premix and squirt it in the carb throat when it's acting up and see if it picks up. If it picks up then it's running lean. Try pumping the primer button on the tank and see if it helps. Chances are it won't. Pressure tanks usually either work or they don't. If it doesn't help then the carb will need to be cleaned and a kit and float installed. Good luck and let us know how things work out.

Cheers....................Todd

 

[wbeaton]

Re: 1957 7.5 evinrude with no power

First, a 1957 7.5 hp doesn't have a lot of power so you might be asking a little much for it to push your 14' boat. With that said, I do have one (out of 6?) that can push a 14' boat 22 kph when I'm alone.

if its actually an engine problem you have two places to look. First are the coils. If it has the original coils then they are bad. No doubt about it. 100% failure rate. If the coils are bad it may act exactly as you described. Second, is the carb. It may need a rebuild. However, inspect the coils first. If they are cracked, sweaty, or discoloured then they are bad.

 

[ebauman]

Re: 1957 7.5 evinrude with no power

Thanks Todd and Wayne for your replies. I do believe the coils are original I will check this winter (winter project) I wasn't sure if I was asking too much of this motor on a 14' boat or not. As a trolling motor on my 16' it does great (no speed required). Great little motor nonetheless .
Eric