Does that look normal? Smoke...

1970 25hp that I just got running. The engine is warm. Gas mix is 50:1 non-ethanol, and not old. I have the low speed needle turned in as much as possible and in the sweet spot for the best idle. The only other outboard motor I've ever owned is a 1970 6hp and it doesn't smoke much at all compared to the 25. Even with the hood on, I have to run it with a fan in front of it. There's a fan directly in front of the motor just out of frame in the video. Is that much smoke normal?

How cold is it outside?

That's my first question too. Seems like vapor to me. If it's not, did you check the thermostat? These babies have to warm up, or that's what your gonna get.

Looks normal to me. Actually, I'm a bit surprised that it runs that well while barrel cruising with the hood on. Get it out of that barrel and onto a boat on the lake and it probably will smoke less after a good hard run.

faztbullet said:

How cold is it outside?

Click to expand...

It was a little cool, but not that bad. It was definitely smoke.

fdrgator said:

Looks normal to me. Actually, I'm a bit surprised that it runs that well while barrel cruising with the hood on. Get it out of that barrel and onto a boat on the lake and it probably will smoke less after a good hard run.

Click to expand...

Awesome, thanks. I hope to take it out for the first time this Saturday. Even with a fan blowing on it, I had to keep the hood on otherwise it would just suck in the fumes and choke out.

timguy said:

That's my first question too. Seems like vapor to me. If it's not, did you check the thermostat? These babies have to warm up, or that's what your gonna get.

Click to expand...

Well, it's a new thermostat. I haven't checked it outside the motor, like in a pot of hot water. I have checked the motor with an infrared thermometer after it's warmed up. The hottest spot on the motor is about a 1" square area beside the freeze plug that will reach around 140f. Most of the block is around 110-120f, I think. The cover on the exhaust side stays 118f. It reaches those temps and goes no higher.

I've replaced points, coils, condensers, thermostat, plugs, all gaskets, carb kit, water pump. I took the motor apart and cleaned it with the exception of separating the crank case (you wouldn't believe the carbon build up). I also disassembled, cleaned, and resealed the gear case.

Excellent, seems you got all bases covered. Yes, the carbon will build up and may need to be removed. I have had some motors here where they are almost completely plugged up. That too, of course, causes rich running and lack of power. Some might want to argue with me on this, but that little 22 cu inch 25, in short shaft and manual start, is the most powerful power to weight ratio outboard, ever made. Great engineering, and I believe Johnson pushed the 22 cu in. first to 25 h.p., not Evinrude.
Might add that your operating temp seems normal. Make sure your fresh air intake openings are free. Sometimes I even drill some 3/8" holes in safe, strategic locations, in order to serve more fresh air to carb intake....why? When trolling on days with no breeze, especially back trolling, fumes can build up causing poor idle and additional smoke. What I have done has worked well for me. This 22 cu in. and also the next generation 20 to 35 horsepowers, have been the "go to" power at our remote NW Ontario camps since way back into the 60's. Of course the 9.9/15 have also been our favorite for guests to operate on their own. We have used Amsoil 100:1 pre mix since 1975 and mixed at ratios between 64 and 100:1. Not a single failure in nearly 50 years now. This is also the way to go if you want to maximize economy and minimize pollution as well as what we covered earlier....carbon build up. I have a little 1965 6 hp Evinrude Fisherman with nearly 4000 hours on it....my very first new outboard. Trolling for Lake Trout sometimes 12 hours in one day. Being personal friends with Al Amatuzio, the founder of Amsoil, he lived only a few miles from us, we got free samples of the 2 stroke 100:1 back even before it was known to the public. Amsoil Saber oil is directed primarily to air cooled 2 strokes, and is a bit more costly. I have been using it since it came out about 10 years ago. Honestly, if everyone in California had been using Amsoil in these recommend ratios....2 stroke outboard motors would probably have never been eliminated. Amsoil is not what many people think, and horrer stories are mostly total BS. You don't build a highly successful company from scratch, in a terribly competitive industry, going up against the oil companies....out of BS.
How about this jug/piston on my Stihl MS660? 17 years old and hundreds of cords of oak, diced to 16". You be the judge.

Wrong------The 22 cubic inch 25 HP was first marketed in 1969 by Evinrude in blue paint and also in 1969 by Johnson in green paint. ----Exact same motors with different paint and slightly different cowlings.

O well, my memory is fading. Thanks for the correction, Racer. Nevertheless, great, great motors. I think they were available in around that same year through Montgomery Wards, right? Just different "artwork". Did they call them a "Sea King"? Seems I worked on an electric start version, tiller. It was blue color. However, there were many Sea Kings over this time period that were really Chryslers too. Gale came around the 50s and 60s. These were Evinrude/Johnson's. I have a very nice 40 horse here in white and red. Think it's a 64. They were marketed by Wards, even starting back in the 30's.
A great brief and entertaining history of Evinrude: Click below about 10 minute read.

https://www-passagemaker-com.cdn.am...chnical/the-story-of-evinrude-outboard-motors