Johnson 6HP, does the smoke output look right?

[Alan_Scott]

I picked this up yesterday and it would only idle with the choke on. I pulled the carb off and cleaned the sludge and varnish out of it and now it fires up and seem to run fine but it's been a long time since I've messed with a 2 stroke and the smoke seems excessive. The fuel is fresh with a 50:1 ratio of Pennzoil outboard oil.

Also, is there a thermostat in it? The heads were warm to the touch but the water coming out of the weep hole always felt stone cold. The water temp in the barrel was probably mid 30's.

I filmed this after it ran for just over an hour in gear at a high idle
http://www.youtube.com/watch?v=dcB4W996HCc&feature=youtu.be

 

[boobie]

Re: Johnson 6HP, does the smoke output look right?

They will always smoke like that in a barrel. Take it to the water on the boat and run the heck out of it and then see what it does.

 

[Cap'n Chaos]

Re: Johnson 6HP, does the smoke output look right?

I'm confused as to what year that is, looks newer than my 65 - but it should have a thermostat in it.

 

[kfa4303]

Re: Johnson 6HP, does the smoke output look right?

I agree. She looks and sounds good to me. It will smoke much less on the open water. It probably does have a t-stat. If it does, they're usually on the back right corner of the power head when looking at the motor with the top to the housing held on by 3 med size bolts. The head should run about 130-140 degree F. The exhaust water may not get very warm, if it's only 30 F outside and the water going into the motor is very cold to begin with.

 

[Alan_Scott]

Re: Johnson 6HP, does the smoke output look right?

I haven't looked the year up yet, the guy I got it from thought his dad had bought it new in the mid 80's.

I'd guess it was running 90-100 degrees on the head, I'll pull the thermostat out and check it on the stove, thx for the location.

After I pulled the starter assembly off, it looks like I could have just pulled the 2 top bolts on it and leaned it away enough to reach the carb bolt, has anyone tried this?

 

[torbjorn]

Re: Johnson 6HP, does the smoke output look right?

You'll be safer to use Evinrude or Mercury TC-W3 oil. That motor
can be opned up to 7.5 hp by removing the carb and intake
manifold and filing out the intak opening to match
the carb throat. 6hp won't plane a 300 lb boat but 7.5 hp
(a 25% hp gain) will. We have a 1981 Evinrude 6 (Belgian
model) so i know.

 

[BoatingCop]

Re: Johnson 6HP, does the smoke output look right?

That motor is either a '77, '78, or '79. Those are the only years that Johnson made those cowlings with that design.

 

[raczekp1]

Re: Johnson 6HP, does the smoke output look right?

yes its definitely made in 76-80 because its painted white and kill button is added

 

[F_R]

Re: Johnson 6HP, does the smoke output look right?

I haven't looked the year up yet, the guy I got it from thought his dad had bought it new in the mid 80's.

I'd guess it was running 90-100 degrees on the head, I'll pull the thermostat out and check it on the stove, thx for the location.

After I pulled the starter assembly off, it looks like I could have just pulled the 2 top bolts on it and leaned it away enough to reach the carb bolt, has anyone tried this?

Yes, that is correct, all you have to do is lean the starter away for access to the nut.

Also, you should understand the cooling system. There are TWO paths through the powerhead for the cooling water. One path is ALWAYS open and flowing. The second path is controlled by the thermostat. After leaving those paths, the water is mixed and discharged out the exhaust. With temperatures in the 30s it just isn't going to get very warm. Probably never warm enough to open the thermostat, especially at slow or barrel speeds.