smoky johnson 25 HP (j25balcnb, s/n b01677).

[saffi]

My johnson 25 HP (j25balcnb, s/n b01677)smokes quite a bit. It is a white "light" smoke. I can't really determine if there's steam in it suggesting a leaky head gasket. Would that show on your spark plugs? I had to clean the carb and someone else ajusted the float. I checked it and he said it should be 19.4 MM.(he used a metal "example" (it is above the float bowl when inverted) Now I read in other posts that the float should be level with the bowl when inverted. The engine runs very well and I have no problems with loss of power or idle problems. It just uses too much fuel (I think). I use it to commute and run it about 20 minutes every day (15 at 3/4 and the rest near idle). I think running rich is what causes the smoke. What would be the expected fuel consumption? I have new spark plugs and they fire well. Checked all fuel lines and made sure they don't leak. Could a stuck ring be a cause? What would point to a stuck ring? Thanks in advance, Saffi<br /><br />One more thing, I plan to use the boat in winter, is there a problem with this outboard and freezing weather conditions?

 

[plywoody]

Re: smoky johnson 25 HP (j25balcnb, s/n b01677).

If you pull the plugs, if one of them looks like it has been steam cleaned, you could have a leak.<br />You can do a compression check as well.<br />How much fuel is it burning after 15 minutes at 3/4 throttle?

 

[saffi]

Re: smoky johnson 25 HP (j25balcnb, s/n b01677).

I just checked and it seems to burn about a US gallon an hour. I thought it was more before. That seems about right so that doesn't worry me too much anymore. I checked the exhaust. On this type of engine the exhaust is above water just below the engine block on the back (why not below water level??) There's definately moisture in the exhaust gasses coming out. I can put my hand in it and it won't burn me so I think it can't be moisture coming from the cylinder as I would think that would be steam. It might have cooled down along the way though. The water temp is about 40 to 50 fahrenheit at the moment. I really need to buy one of the books on this engine. Where is the outlet of the remainder of the cooling water? Is it pumped into the exhaust system? I have a sailing boat with a Renault diesel engine and I made an exhaust outlet where the cooling water is sprayed straight into the exhaust fumes right after leaving the engine both to cool the exhaust pipe and to dampen the sound. Is it the same on this outboard? Right now I think the problem is wrong timing and maybe the float in the carb.... Anybody have suggestions on what book to buy? I also have a 60' model 20 HP johnson with plenty problems. I would like a book that would cover both engines. <br /><br />Still trying to fix it... help always welcome.