Fogging oil won't kill engine

banderberg

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I'm in the process of winterizing my 3.0 and when spraying fogging oil down the carb the engine won't die. It struggles a bit but just keeps going. I sprayed for over twenty seconds. Just wondering why and if it matters. I ended up just killing the engine right after spraying.
 

tpenfield

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Often the spray does not give enough fogging oil to stop the engine. You can try 2 cans of spray going at the same time. Also, make sure you are at the lowest idle.

My 454 Merc would keep running even with 2 cans of spray going . . . I always just shut the engine off and call it good.
 

Bondo

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I'm in the process of winterizing my 3.0 and when spraying fogging oil down the carb the engine won't die. It struggles a bit but just keeps going. I sprayed for over twenty seconds. Just wondering why and if it matters. I ended up just killing the engine right after spraying.
Ayuh,...... If it's just for this winter,....... It'll be just fine,.......

If it's a 10 year lay-up,....... Maybe not,.....

I don't fog out any of my motors, myself,.....
 

Lou C

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I have to use 2 cans on my 4.3 4bbl to get it to stall…
 

Scott Danforth

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I fogged once..... 30 years ago.

However spray for 10 seconds and shut down
 

Silvertip

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Foour stroke engine have cylinder walls and all internal moving parts lubricated with pressurized or splash oiling. There is no need to fog them except for perhaps multi-year layups. Two strokes (outboards and snowmobiles primarily) needed to be fogged because of the wet environment and the fact that they burn off oil on cylinder walls. Two stroke oil is designed to burn off. 4-stroke oil not so much.
 

Drcoffee

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Last season I couldnt kill mine spraying down the primary so I had to shut it down. Had a small amount of smoke on start up this spring. This year, again, engine stumbled but would not stop Until I sprayed into the secondary plate. Then it chugged to a stop.
 

racerone

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If engine is in good shape , strong spark, good compression it won't stall with a bit of fogging oil introduced.
 

ROY WILLIAMS

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I was shutting the fuel valve then spayed the fogging spray can oil.. did it 20 sec ..idle is around 650 RPM...
then I put marvel mystery oil in the cylinders 1 oz...
my engine is over 40 yrs old no engine damage..
used the plastic bag to seal the carb...
 

crazy charlie

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I'm in the process of winterizing my 3.0 and when spraying fogging oil down the carb the engine won't die. It struggles a bit but just keeps going. I sprayed for over twenty seconds. Just wondering why and if it matters. I ended up just killing the engine right after spraying.
Had similar issue the 1st time I fogged my Mercruiser 30 years ago.Since then I have a can of fogging oil in 1 hand which I spray in slowly for at least a minute and a cup of MMO in the other hand .When I want the engine to stall I dump the MMO in the carb as I am loading it with fogging oil full blast. This method will stall it.Charlie
 

isaacs

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If you stay away from ethanol contaminated fuel you shouldn't need any additives or fogging for a simple winter layup. Just shut it off and have a beer!
 

Drcoffee

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Can anyone explain why you should fog the engine for any more than 20 seconds. The engine at idle is sucking air into each cyl at a rate of 5x per second. Any oil that makes it to a compession stroke will be burned out and exhausted. It would almost be more beneficial to fog heavily as it stalls so the oil will drain into the cyls. But why fog for a minute?
 

Bondo

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Can anyone explain why you should fog the engine for any more than 20 seconds. The engine at idle is sucking air into each cyl at a rate of 5x per second. Any oil that makes it to a compession stroke will be burned out and exhausted. It would almost be more beneficial to fog heavily as it stalls so the oil will drain into the cyls. But why fog for a minute?
Ayuh,....... 'cause marine suppliers have convinced anal diy boaters, that it's the Only way to put their baby to bed,.... :)
 

ROY WILLIAMS

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Can anyone explain why you should fog the engine for any more than 20 seconds. The engine at idle is sucking air into each cyl at a rate of 5x per second. Any oil that makes it to a compression stroke will be burned out and exhausted. It would almost be more beneficial to fog heavily as it stalls so the oil will drain into the cyls. But why fog for a minute?
my engine is 1986 and is now .. I fogged in the fall ,engine runs time around 20-40 sec....no engine damage .. then I put in Marvel mystery oil I ounce each cylinders in the spring and a delayed it a few days ago ..then engine runs it on the muffs ...engine runs like a idle speed no rough idle ..
I put the plastic bag over the carb .... sealed it ..
many people had a lot of rust in the cylinders and the idle is rough over in the winter /spring ...
 

Lou C

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It really depends on your storage climate. In the frozen north where it never warms up all winter there isn't enough moisture in the air, to matter. However in a temperate climate like where I am, we go from zero to 40 to 60 degrees in the winter. That, combined with moisture being a coastal region, mean a lot of condensation on any metal surfaces. If you open up the cover to charge the batteries half way thru winter on a nice warm winter day, you will find the engine sweating in condensation which also happens inside. So for me fogging makes sense.
 

QBhoy

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I alternatively just run 2 stroke through her, right before taking her out
 

Long2757

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I prefer to shoot a little in the carb for a few seconds and when the engine starts to chug kill it. If you really want, pull the plugs and fog the cylinders individually. Then if the plugs are old or wet replace them in the spring.
 
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