'79 Evinrude won't stay running

[backlash1]

On a recent trip to the lake, my '79 evinrude 85 hp quit on me. i could pump the bulb a few times to get it to start but it would just die after a few seconds. my gas gage was on the fritz, so i thought i might have just ran it out of gas. yesterday i put 6 gallons in and the motor would start right up fine but would not keep running more that 2 or 3 seconds. one time i tried it, i had my son turn the key and i kept pumping the bulb and it ran okay until i stopped pumping. i haven't looked at anything but the filter yet, which was clean. any suggestions? carb problems? should i just order rebuild kits or is there more i should check first? thanks in advance for the help guys.

 

[ob]

Re: '79 Evinrude won't stay running

If you can keep it running by continually pumping the fuel bulb,it sounds to me like a failed fuel pump.First item I would check is the pulse hose that drives the fuel pump.

 

[backlash1]

Re: '79 Evinrude won't stay running

is the pulse hose the short one between the outboard fuel connector and the pump? i just took the hood off and pumped the bulb a couple times and if i put my head real close, it almost sounded like air leaking out of the connector. could that cause that sort of problem?

 

[ob]

Re: '79 Evinrude won't stay running

Absolutely.An air leak/fuel leak can cause your problem as well.The pulse hose runs between the crankcase and the air motor portion of the fuel pump.The pump diaphragm is actuated by the pressure pulses present in the crankcase via this hose.

 

[backlash1]

Re: '79 Evinrude won't stay running

on the pump itself, i see a fuel hose that comes in through the filter and a hose that comes off the pump then branches off to each carb. there is a small hose that runs from the crankcase to the bottom of the housing that is in front of the carbs. is that the pulse hose?

 

[tashasdaddy]

Re: '79 Evinrude won't stay running

you found it the pulse hose, an air leak will stop the fuel pump. also, investigate the coupling connection and connecting fuel lines. if they haven't been changed since new, probably time. on another point once running doing a decarb (engine faq forum) with seafoam deep creep, will improve your performance.

 

[ezeke]

Re: '79 Evinrude won't stay running

Actually, I don't think that you have a pulse hose attached to the fuel pump on your motor. The pulse is from the vibration and requires a good tight fit of the gasket between the pump and the motor..

http://epc.brp.com/scripts/EmpartIS...mode=3&cat=25&assem=43652&hideMsg=&imgMap=Yes

 

[backlash1]

Re: '79 Evinrude won't stay running

okay--- here's what i just tried. i took off the black plastic cover from the front of the motor in front of the carbs. i shot a generous dose of carb cleaner into both carbs and let it sit for about 30 mins. i then took a squirt bottle with premixed fuel and put a couple squirts down each carb throat. started right up and i continued to give each carb a squirt every few seconds for about 15-20 seconds. then i quit squirting and the motor ran by itself just fine for almost 10 minutes on the muffs in the driveway until i shut it off with the key. was that a fluke or have i scared away the gremlin?

 

[backlash1]

Re: '79 Evinrude won't stay running

just started that motor again--only this time with no help from the little squirt bottle, just turned the key. again it ran until i shut it off. should i consider my problem solved? if i had just run out of gas as i originally suspected, is it possible that sediment or some temporary obstruction or buildup or clog or air in the gas lines or some other condition that goes along with running out of gas could have caused my problem?

 

[OBJ]

Re: '79 Evinrude won't stay running

Unless there was some restriction in the carb throats or in the high speed tubes, you didn't do much for the carbs. You need to get some SeaFoam into the carb bowls. Deep Creep works also. But on the other hand, I've seen some crazy stuff happen with outboards.

You'll know once you get it into the water.d