Evenrude 1988 48 SPL - Roaring Engine Help!

[adlury]

I am trying to sell my boat (1971 Crestliner) with the above Engine. When I start the engine it idles but eventually revs to a full wide open roar within 3 or 4 minutes. The only way I can shut it down at this point is to disconnect the gas line into the engine- turning the key off and shutting off the battery switch does nothing. Being next to a complete moron when it comes to most things electronical, I somehow have a feeling that it has something to do with voltage? I know the mechanic who has worked on the boat before replaced the voltage regulator a couple of years ago- is this the same problem? Pretty embarrasing when you are showing the boat to a potential buyer and you can't shut the engine off !!!! All input would be greatly appreciated...thanks

Unplugged in Massachusetts..

 

[fireman57]

Re: Evenrude 1988 48 SPL - Roaring Engine Help!

When you are running this engine are you doing it in a barrel or on muffs? A barrel seems to be better because you have the backpressure that helps your idle. Nothing is wrong with muffs though. Make sure your throttle linkage isn't somehow moving due to the vibration of the engine running. Just some ideas.