'81 Johnson 8hp won't go full speed

[woodbox]

We're the proud owners of a whaler and Johnson outboard - 8hp Sailmaster - that have been in my family for 35 years! As two women with little outboard experience, we're somewhat reluctant to take on major repairs, yet would be willing to try fixes that sound pretty simple. Otherwise, we'll need to know if we're out of our league and need to pull it (aaarrgghh!!) and take it to the local repair shop (they know it well...).

The issue is that it starts okay and then runs (though a little rough) at low speed, then when we try to run it full throttle, it sputters a lot and never gets up to full speed - maybe gets to half-speed. The vent IS open on the gas tank - that was one suggestion.

Any help for two enthusiastic, but not-so-mechanical, boaters would be VERY welcome!

 

[iwombat]

Re: '81 Johnson 8hp won't go full speed

When is the last time the carburetor was serviced? Sounds like you may be due for a rebuild. However, there's some other tests that you should perform first before diving into the carb (fairly easy do-it-yourself repair).

Do a search on spark test and compression test. Ask any questions you need, then post the results.