intense white smoke

[JimmyG]

Finally getting my '94 70hp to show some life. After rebuilding carbs and replacing fuel pump, I can get her to start up with the help of a little starter fluid. A ton of white smoke comes pouring out of the exhaust (more than normal 2-cycle exhaust, I am using 50:1 oil gas mix). It is also sputtering thick oil from the exhaust as well (presumably gear oil). I am fearing bad seals in the lower unit, Is that the obvious problem or is this just a product of sitting for several years in the previous owners garage?

Jim

[Ken]

Jim,
You will see a lot of white smoke on start-up for that pre-mix. My C115 does the same thing.
As far as oil coming out the prop exhaust, if it is black, dont' worry about it. If it is clear, then indeed it would have to be lower unit gear oil.
If you determine that the lower unit seals are not leaking, then you might do a shock treatment with SeaFoam or RingFree to clean out some of the carbon.
Good luck [img]smile.gif[/img] ,
Ken K

[Dennisg]

JIm, Yamaha warns against using starting fluid, so do not use it, it could cause melt down of pistons, and all kinds of other problems. Also, determin where the oil is comming from, more than likely it is unburned oilcomming from the exhaust, if it is don't worry about it, it is normal. Lots of white smoke is the fogging oil burning away, you will think it is all burnt away, then the first time you put it in the water, it will happen again, but this time not as much. Again this is normal.
Dennis

[ July 11, 2006, 06:13 PM: Message edited by: Dennisg ]

[jb123]

heavy white smoke...what do your plugs look like??? not rusty ?

[JimmyG]

Plugs are fine..

I drained the gear oil, it appeared fine, so I believe the seals are still good. Maybe I am just burning oil off in the exhaust, plus the 50:1 mix.
I will avoid using starting fluid, though I have been unable to get her started otherwise.

Is there an easy way to determine if the enriching pump is supplying fuel to the crankcase? I was told the history of this motor always included fuel problems and hard starting, and the enriching pump was hacked up quite a bit..

thanks all for input.

Jim