1965 33hp johnson slowly stalled at WOT

[stone4141]

I took my boat and motor on there maiden voyage yesterday. Everything was great all day. Until the end at WOT the motor just slowly died down then quit. It started right back up ran rough for about 10 seconds then was fine. Ran it for a couple minutes then went in. It has been suggested that it seized up briefly, overheated or maybe ignition problem. It does not appear to have overheated that was the first thing I checked. Motor was no warmer than normal. Primer bulb was still tight. Checked the compression after and it was perfect. My only thought was a bad fuel pump or maybe my high speed adjustment was incorrect. I am going to put in new plugs and a fuel filter and run it at 25:1 instead of 50:1. Any other thoughts?

 

[kbait]

Re: 1965 33hp johnson slowly stalled at WOT

50/1 is specified for your motor. The 'slowly died down' sounds like a fuel delivery/carb issue. I'd first confirm spark w/a tester to be sure of 1/4" blue snappy bolt in open air. (you need that to fire .030" plug gap under compression). If that's good, check all fuel hose fittings (replacing fuel lines under cowl never hurts!) and give it another try. If it happens again, squeeze the bulb quickly to see if it's a fuel pump issue (bulb overrides pump). If that does nothing, quickly apply the choke and see if it speeds up. If yes, dismantle and clean carb. Good luck!