Early 80's 150 Johnson Smoke Show

[justin310]

Fantastic site and some amazingly helpful people!! I own a 150 HP Johnson outboard (early 80's) that takes a while to start up but once it does, the smoke (white) fills the marina and chokes us out. At idle it continues to smoke heavily and every time its started it smokes quite badly. I have tried reducing the gas/oil ratio (not sure what is should actually be...was told 50:1) significantly but the problem persists. Is this an expensive fix? My dad's convinced its ready to become an anchor but I'd love to save it...any suggestions would be greatly appreciated.

 

[angus63]

Re: Early 80's 150 Johnson Smoke Show

Welcome!!!<br />White smoke is indicative of water (moisture)in the combustion chamber. <br />1) Try fresh fuel from a remote tank and see if it still occurs. If not, your fuel is probably moisture laden.<br />2) Check all 6 plugs and see if one or more looks steam-cleaned compared to the rest. If so, a head gasket may cure it. Or it may be a porous cylinder (lets hope not!!).<br />3) Do you have a water separator and has it been changed?<br />Give em a try and let us know...<br />Good luck

 

[justin310]

Re: Early 80's 150 Johnson Smoke Show

Thank you very much for the response. I'm admittedly a rookie when it comes to boats and motors. Do you think that the steaming you describe is as choking as this seems to be? Its a very rich smelling smoke. I have no idea about the water separator but I know I haven't changed it. Should I be running a 50:1 ratio?

 

[angus63]

Re: Early 80's 150 Johnson Smoke Show

Usually rich fuel is dark smoke and too much oil is blue smoke. Yes, the ratio is 50:1 (16 oz TC-W3 oil to 6 gallons of 87 octane fuel). Post back what spark plugs you have and what the gap is at also. As far as choking, I'm not certain what you are asking. If you do not have a filter/water separator in line, I would suggest installing one.<br />1st post the plug #'s<br />2nd Try a different remote tank with fresh fuel<br />and trace from the existing tank to the motor for a filter (looks like a spin on oil filter). If there is one, replace it immediately.<br />Your plugs should be UL77V or L16V champions (surface gap plgs - no electrodes) if they are not already.<br />Good luck

 

[justin310]

Re: Early 80's 150 Johnson Smoke Show

Okay, took a look at the motor this past weekend. All 6 plugs are UL77V and were quite oily, not steam cleaned. Fuel is all new and the motor still smokes every time it is started. The smoke smells quite rich. (#'s on the motor if that helps; J150TLCSA J5348292...can I learn anything from that?)<br />Looks like cooling water is getting into the wrong parts of the engine while its running...right? what are your thoughts?<br />Thank you...

 

[Cricket Too]

Re: Early 80's 150 Johnson Smoke Show

A lot of times blue smoke looks white to the untrained or unknowing eye, I had an older 150 and that bad boy smoked bad when first started, I have 2000 200hp's now and they smoke even worse when starting cold and even when hot, but not as bad. If it's choking you out than it's most liley 2 stroke oil doing it. These old carbed motors just smoke like that, but make sure your mixture is really 50:1 and not more, 50:1 is plenty of oil. I would worry more first about why it's so hard to start, make sure your choke is working properly, your motor is a 1980 so there is no primer instead of a choke. If it is still running nice, I would say it's far from being an anchor as long as you take care of it, I have a 1975 70hp that's still going strong.<br /><br />P.S. When was the last time the carbs were rebuilt?

 

[justin310]

Re: Early 80's 150 Johnson Smoke Show

We just bought the boat and motor last year and I would guess that the previous owner hadn't done it for a while. There is an oil slick on the water after we start it too...does that give any clues? We thought it was a procedural problem we were guilty of...not sure exactly what the correct procedure is for starting a cold engine...choke and lever up to start, just lever up to start, just choke?? Do you think a carb rebuild would rid us of the smoke problem a bit...the neighbours in there luxury boats don't care much for the smoke show.<br />Thank you.

 

[ddbyrd3]

Re: Early 80's 150 Johnson Smoke Show

I have a 1981 140 Johnson, starting procedure has always been; fast idel lever 1/2 way up, push key in to prime and turn key while pushing in the key.. Once fired release the key..<br /><br />Thats my procedure wether it is 40* outside or 120* outside.<br /><br />Hope that helps..

 

[justin310]

Re: Early 80's 150 Johnson Smoke Show

I'll try that this weekend thank you.

 

[rodbolt]

Re: Early 80's 150 Johnson Smoke Show

hello<br /> does the motor still have a VRO pump? if not have you tested the two block mounted pumps or just replace them cause they get old and nothing lasts forever. after that test the recirc check valves.if the valves have carboned up it allows an extra rich mix to puddle. after shutdown and the fuel evaporates it causes some serious smoke at the next start up.