'67 Evinrude 33 hp idles but has no power

[jw_928]

I have a '67 Evinrude 33 Hp sea-king or sea twin, I can't remember. It was sitting for three years before I bought it this year and has run well for 10 outings (6 hours) with a slight cough a low speed.<br /><br />Currently it starts fine and idles ok, but the idle never quite gets all the way up, and the engine never gets out up to full speed. (probably not even half speed).<br /><br />It did rain recently if that means anything.<br /><br />I've never worked on a boat motor but I have worked on some older cars. Where do I start? I guess I'll pull the plugs tomorrow. What else should I check?<br /><br />Thanks,<br />John Welch<br />Okauchee, WI

 

[jw_928]

Re: '67 Evinrude 33 hp idles but has no power

Also, would any know the recommended fuel mixture? I was told 50:1, so perhaps that's the problem.<br /><br />Thanks again, <br />John

 

[jw_928]

Re: '67 Evinrude 33 hp idles but has no power

Also, Also, I was told by the marina that the compression was fine.<br /><br />Thanks.

 

[Bob_VT]

Re: '67 Evinrude 33 hp idles but has no power

50:1 is the correct ratio for the pre-mix.<br /><br />There is a big list of things to check but i will give you a few to start.<br /><br />Is the linkage in adjustment allowing the carbs to go wide open?<br /><br />Do you have spark in both cylinders? It will run and idle on only one cylinder and darn near sound okay. Remove one wire (by the boot) when it is idling and see that the spark from the wire jumps to the block, then try the other.<br /><br />Are your carbs clean? The low speed idle circuts and the high speed jets tend to get a build up of gunk on them.<br /><br />Start there and let us know.<br /><br />Bob

 

[fireman 757]

Re: '67 Evinrude 33 hp idles but has no power

I agree with Bob VT. Probably a bad coil.