Winterizing a 25 hp Merc outboard

[GordM]

I want to make sure I do this right. So the gist of the question is how do I properly winterize this motor?

 

[MH Hawker]

Re: Winterizing a 25 hp Merc outboard

Depending on the year and if its carbed or injected its very simple, the cylinders need to be sprayed with a fogging oil and the LU oil changed and if carbed the motor run dry of fuel.. I run mine dry of fuel then spray fogging oil into the carb so it coats the mains and cylinders then change out the LU oil and do a vacuum / pressure test and refill if it passes. I run that test just to see if it needs new seals so I can fix it over the winter, most don't do that test. O and store it with the LU straight down so any water left in the motor will drain.

I am sure many will kick in other things and ways. A lot do nothing at all, many don't run dry, and a lot don't bother to change the LU oil.

 

[GordM]

Re: Winterizing a 25 hp Merc outboard

Depending on the year and if its carbed or injected its very simple, the cylinders need to be sprayed with a fogging oil and the LU oil changed and if carbed the motor run dry of fuel.. I run mine dry of fuel then spray fogging oil into the carb so it coats the mains and cylinders then change out the LU oil and do a vacuum / pressure test and refill if it passes. I run that test just to see if it needs new seals so I can fix it over the winter, most don't do that test. O and store it with the LU straight down so any water left in the motor will drain.

I am sure many will kick in other things and ways. A lot do nothing at all, many don't run dry, and a lot don't bother to change the LU oil.

Thanks very much. Do you spray the carb while it is running?

 

[MH Hawker]

Re: Winterizing a 25 hp Merc outboard

Yes the fogging oil is sprayed in while its running or being cranked so it will coat the intake, reed valves, cylinder walls and the main bearings, crank shaft, connecting rods and bearings, exhaust and other assorted internal parts to prevent rust over the storage period.

 

[GordM]

Re: Winterizing a 25 hp Merc outboard

Yes the fogging oil is sprayed in while its running or being cranked so it will coat the intake, reed valves, cylinder walls and the main bearings, crank shaft, connecting rods and bearings, exhaust and other assorted internal parts to prevent rust over the storage period.

Thanks again