1982 4.5 Evinrude runs for +- 15 minutes then slows to idle then quits will restart.

[pawnature]

I have a 1982 evinrude that runs great for about 15 minures then it will slow to idle and run for a minute or two then quits. It will restart almost immediately though. Any thoughts.

 

[AEROCOOK]

Re: 1982 4.5 Evinrude runs for +- 15 minutes then slows to idle then quits will resta

I have a 1982 evinrude that runs great for about 15 minures then it will slow to idle and run for a minute or two then quits. It will restart almost immediately though. Any thoughts.

It could be starving for fuel.
What is your re-starting procedure after it dies?
Is the vent on the tank open?
If you pump the primer bulb during incident does it improve?

 

[twocyclemania]

Re: 1982 4.5 Evinrude runs for +- 15 minutes then slows to idle then quits will resta

This is a stretch but it's possible that there's a piece of some crap floating in the carb bowl and eventually clogs up the the jet. Sorta like a pinball in a pinball machine. Once it dies (no more intake suction) the 'particle' may float to the top or out of the way. And the cycle goes on.

I had an incident with a 7.5 (80's) Johnson that would overheat. After shutting down you could start it and run again for a while and than it would overheat again and again. Long story short: I found a small piece of rubber (probably from the impeller or a seal) was floating around inside the the cooling chamber. After a while it would plug up the small hole where the water exited and thus it would overheat. Two different systems but a possible similar problem. I'm really curious to what you might find in the bowl. Than again I may be way off.

 

[pawnature]

Re: 1982 4.5 Evinrude runs for +- 15 minutes then slows to idle then quits will resta

Aerocook, when it dies I Choke it and after a couple cranks it starts right up. When it cut back to an idle before dying I checked the ball pump and it was hard. I didn't check the vent but will.

 

[AEROCOOK]

Re: 1982 4.5 Evinrude runs for +- 15 minutes then slows to idle then quits will resta

Aerocook, when it dies I Choke it and after a couple cranks it starts right up. When it cut back to an idle before dying I checked the ball pump and it was hard. I didn't check the vent but will.

Try pumping the primer as it's starting to die and see if it improves.
Usually if the vent on the tank is closed, the primer bulb will collapse due to the vacuum being created. I've seen older primer bulbs where the rubber is extremely hard and it would take a lot of vacuum to make one like that collapse so it's still worth checking out that vent.
Another possibility is that air is getting into the fuel system possibly at the fuel connectors if the o rings are bad. If you can find / borrow another "known good" fuel line that would be a quick test to eliminate or confirm that as the cause.

 

[pawnature]

Re: 1982 4.5 Evinrude runs for +- 15 minutes then slows to idle then quits will resta

Try pumping the primer as it's starting to die and see if it improves.
Usually if the vent on the tank is closed, the primer bulb will collapse due to the vacuum being created. I've seen older primer bulbs where the rubber is extremely hard and it would take a lot of vacuum to make one like that collapse so it's still worth checking out that vent.
Another possibility is that air is getting into the fuel system possibly at the fuel connectors if the o rings are bad. If you can find / borrow another "known good" fuel line that would be a quick test to eliminate or confirm that as the cause.

I took it out again today. (By the way the vent was open). Ran for about 10 to 15 minutes the shut down. Tried pumping the bulb while it was slowed nothing. Restarted it without much trouble and it took right off. It then throttled back abruptly. Ran that way for about a minute and then picked back up. I throttled it back to about 1/2 to 3/4 throttle and it ran good the rest of the day. Go figure. But definitely something to do with fuel i'm thinking.

 

[nwcove]

Re: 1982 4.5 Evinrude runs for +- 15 minutes then slows to idle then quits will resta

start with the cheap stuff and rebuild the carb.....not just throw in a kit.....clean it properly! jmo