1977 70hp Evinrude problem

[Rod_Bender]

I just puchased my first boat 1977 16' glastron with a 70hp 2stroke evinrude. Boats in great shape. Motor runs well with the muffs on in the drive way it also starts and idles well in the water but when I go to accellorate it bogs down and starts to die. Sometimes I can power through it others i just gotta find that sweat spot and it'll get moving. Once it gets up and moving it runs fine. Next problem come when i shut down the engine it's 50/50 if it's gonna start or not. If not I have to let it sit for about an hour and it starts back up and the process starts all over again. When not starting it turns over and sound like its almost there but it doesn't. It has good compression good spark I changed the fuel lines & primer bulb and the gas is new. Anybody have any ideas???????????

 

[oldrudedude]

Re: 1977 70hp Evinrude problem

Does it help to choke it when it stats to bogg? Carbs probably need cleaning.

 

[seminol7]

Re: 1977 70hp Evinrude problem

I'm thinking more of timing issue

 

[Rod_Bender]

Re: 1977 70hp Evinrude problem

well im gonna pull the carbs off tonight check the high speed jet and give it a good clean see if it needs a rebuild and go from there.

 

[Les Young]

Re: 1977 70hp Evinrude problem

Have you checked the fuel line: bulb,connections&line itsself ??? Could be sucking air from a small pinhole in the line or bulb or at a clamp at one of the connections.

 

[Rod_Bender]

Re: 1977 70hp Evinrude problem

well I have changed fuel lines primer bulb and I pulled the carbs of and cleaned everything. Took the boat out last night it started up fine idled well but when I went to give it gas it still bogged down. I found if I push the key in and choke it it picks up and runs great. I have the boat in automatic choke. Im not really sure what controls the choke or why this is seems to fix the bogging down . Any ideas?

 

[bktheking]

Re: 1977 70hp Evinrude problem

well I have changed fuel lines primer bulb and I pulled the carbs of and cleaned everything. Took the boat out last night it started up fine idled well but when I went to give it gas it still bogged down. I found if I push the key in and choke it it picks up and runs great. I have the boat in automatic choke. Im not really sure what controls the choke or why this is seems to fix the bogging down . Any ideas?

Choking enriches the mixture for cold starting, if its runs properly with the choke on the you either have a vacuum leak somewhere or the carbs are still dirty. If you choke a properly tuned engine it will die from getting too much fuel.

 

[Rod_Bender]

Re: 1977 70hp Evinrude problem

thanks for the info the engine does cut out slightly when I apply the choke but as soon as I let the button go it starts running properly. I have carb rebuild kits coming in the mail. Hopefully after the rebuild things will start working properly.