How do you fog the engine?

kaydano

Well-Known Member
Messages
4,287
Reaction score
2,163
Obviously you take the plugs out and spray oil into the cylinders and crank the motor to spread it around, but isn't gas getting injected into the cylinders when you do that???  Do you have to shut off the gas?  How do you do that?

Andy/Derrick - Don't tell me to put it in gear and turn the prop by hand!  ha ha ha.
 
You probably don't want to remove the spark plugs on your F150 unless you're replacing them.  I wouldn't be surprised if our plugs must be index'd anytime they're removed/replaced--to point the electrode in the proper direction of the valves.

Most of the fogging in the past have been done on 2 stroke motors.  You'd get the engine running, warm it up and then cut off the gas supply.  When the engine starts to stumble, you spray fogging oil into the carb. throats and the engine would quit.  After that, you could remove the plugs and spray thru the holes some.

My dealer says to fill up the fuel tank and put your fuel additives in it.  Use 100% gasoline if available.  Put a Battery Tender on your battery.  And that's about it.  Of course this is a good time to change the lower unit grease and do an oil change.

I've never been one to use fogging oil on my old Yamaha 115 hp 2 stroke.  There again, our southern winters are not as harsh as in the far north. 
 
Last edited by a moderator:
You don't have to fog a 4-stroke.
 
Obviously you take the plugs out and spray oil into the cylinders and crank the motor to spread it around, but isn't gas getting injected into the cylinders when you do that???  Do you have to shut off the gas?  How do you do that?

Andy/Derrick - Don't tell me to put it in gear and turn the prop by hand!  ha ha ha.
If you did take that route I'd recommend a smaller diameter prop to save yourself some time!!!!
 
Yamaha recommends fogging.  Scroll to page 2 for the 4 stroke http://www.yamahaoutboards.com/sites/default/files/pdfs/Winterize_V1_3-FINAL.pdf

The way i do it is to remove the fuel rail on my outboard t50 by removing the 2 screws that hold it in place.  I then pull out the injectors and spray the inside with store-rite yamalube fogging oil with the injectors just hanging loose. I crank the engine a few times, it does spray fuel all over but it dries up pretty quick.  There maybe a better way to do this, but this has worked for me a couple years so far.

thanks,

Alex...
 
Thanks Semper.  This says remove plugs, squirt an ounce of "Storage Seal and Rust Inhibitor" into each cylinder, then run the motor through a start cycle.

Perhaps "fogging" technically refers to spraying oil into the carburetor.  But for fuel injected engines it's not technically called "fogging", (more like squirting) but it essentially accomplishes the same thing, so maybe it gets called "fogging" but it really isn't?  I assumed the two were the same thing. 

Mercury doesn't say anything about shutting off the gas.  Since they say "run it through a start cycle" (which I assume means the motor starts briefly before you shut it down immediately) that would burn off any gas, but wouldn't be enough time to burn through all the oil you squirted in there?  Sound right?
 
Last edited by a moderator:
Dan,

Be careful, it says ONE start cycle which I think means one crank revolution to "spread" the oil. Anymore than that and the rings will start scraping away the oil on the walls. With the plugs out you should be able to spin motor by hand. That way you know you only spin once.

• Remove pencil coils and spark plugs.

• Spray approximately 30 ml (1 fl oz) of Storage Seal Rust Inhibitor into each spark plug hole.

• Actuate key/push button start switch to crank the engine through one start cycle, which will distribute the storage seal throughout the cylinders.

• Install spark plugs and pencil coils.
 
Last edited by a moderator:
I only turn the flywheel manually after spraying the oil into the spark plug holes. 

Make sure to leave the motor in the full down position to allow any trapped water in the engine to drain.
 
You really don't have to fog a 4 stroke in California, sounds like it might be easier to move
 
Back
Top