Fogging your engine?
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Fogging your engine?
OK this may be a weird question but I can't remember ever reading anyone doing this so I thought I would ask. Last week when I was putting my boat away I went through all of the steps including spraying fogging oil in the engine through the carburetor and then through each spark plug hole. For those of you with boats you know this is the "required" technique for putting your boat up for the winter. The point of the fogging oil is to coat the cylinder walls with oil for the winter sleep. In the spring it smokes like crazy for a few minutes and then runs great. My boat engine is a marine version of a Chevy 350 with most of the parts the same as a auto version.
Why is this not a standard procedure when we put up our cars? Do any of you do this today?
Why is this not a standard procedure when we put up our cars? Do any of you do this today?
Instructor
Joined: May 2011
Posts: 163
Likes: 0
From: Clayton NC
My car sat for about 20 years before we started it up this summer. But before we started it, I pulled the spark plugs and fogged each of the cylinders and manually turned the motor over. I just put the car up for the winter but did not fog the engine. Of course, the garage is heated so I don't think fogging is necessary in my case.
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Why would you say it is a waste of time? Is that your opinion or based on some facts? Nothing wrong with it being your opinion I am just wondering why car people, including myself, don't do it - is there something different about it that I am not seeing. Boats are also stored for 6 months but, according to my boat friend mechanics, close to 100% of them are fogged.
Of course it could be that fogging your boat is also a waste of time and money that people get convinced they need to because everyone else does.
Of course it could be that fogging your boat is also a waste of time and money that people get convinced they need to because everyone else does.
Safety Car
Joined: Jul 2009
Posts: 3,719
Likes: 95
From: Saskatchewan, Canada
Why would you say it is a waste of time? Is that your opinion or based on some facts? Nothing wrong with it being your opinion I am just wondering why car people, including myself, don't do it - is there something different about it that I am not seeing. Boats are also stored for 6 months but, according to my boat friend mechanics, close to 100% of them are fogged.
Of course it could be that fogging your boat is also a waste of time and money that people get convinced they need to because everyone else does.
Of course it could be that fogging your boat is also a waste of time and money that people get convinced they need to because everyone else does.
Last edited by bkvette3; Nov 12, 2011 at 09:31 PM.
Burning Brakes
Joined: Feb 2009
Posts: 780
Likes: 1
From: Shelby NC
Why would you say it is a waste of time? Is that your opinion or based on some facts? Nothing wrong with it being your opinion I am just wondering why car people, including myself, don't do it - is there something different about it that I am not seeing. Boats are also stored for 6 months but, according to my boat friend mechanics, close to 100% of them are fogged.
Of course it could be that fogging your boat is also a waste of time and money that people get convinced they need to because everyone else does.
Of course it could be that fogging your boat is also a waste of time and money that people get convinced they need to because everyone else does.
Advanced
Joined: Apr 2011
Posts: 84
Likes: 0
From: Mobile Alabama
IMO - not a waste of time - I fog my 115 HP Mercury outboard ever fall. Same thing with the lawn mower, weed trimmer, etc. Never any issues. I too wonder why this is never done to cars stored during the winter months. Can't hurt!!! As mentioned - coats the cylinder walls and internal parts. I have fogged cars that were put up for the winter months and never had any problems.
Last edited by kf4cln; Nov 12, 2011 at 10:04 PM. Reason: alabama spellin
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
I guess this is my point/question. Three of us, so far, fog our boat engine but none of us fog our car. I just think that is strange.
I spend some time on a few boat forums and I have never seen any winter storage articles that don't include fogging yet I have never seen a car thread saying you should do it to your car.
I do have two engines on stands for a couple cars I am doing and I have squirted oil in the spark plug holes. It just seems the fogging oil would do a better job - talking myself into it!
I spend some time on a few boat forums and I have never seen any winter storage articles that don't include fogging yet I have never seen a car thread saying you should do it to your car.
I do have two engines on stands for a couple cars I am doing and I have squirted oil in the spark plug holes. It just seems the fogging oil would do a better job - talking myself into it!
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Safety Car
Joined: Oct 2005
Posts: 3,570
Likes: 1
From: Algonac Michigan
Boat engines should be fogged due to the fact that the large majority of them are 2 cycle engines.
A 4 cycle engine should not need to be fogged if it being stored for a year or less.
I fogged my 5.7 in my Carver for years till a marine mech. that wasn't interested in taking ALL my money set me straight.
I haven't fogged it for 4 years now with no ill effects.
A 4 cycle engine should not need to be fogged if it being stored for a year or less.
I fogged my 5.7 in my Carver for years till a marine mech. that wasn't interested in taking ALL my money set me straight.
I haven't fogged it for 4 years now with no ill effects.
Burning Brakes
Joined: Jun 2009
Posts: 840
Likes: 4
From: Syracuse IN
We winterize we over 300 boats a year, most all are 4 stroke. We only fog the engines of boats which are to be shrink wrapped, which are very few for us. We store just about every boat inside. In fact, new EFI with Catalytic convertes can not be fogged, or damage can be done by the foggin oil. It can also coat the MAP sensor's which can send an incorrect signal to the ECM. As for the Vette, I do not fog at all, as for our snowmobiles, we don't fog them either any more. I believe if you are going to store the engine for longer than 6 to 7 months fog it, but for normal storage, no real reason to. How long do cars set on a lot or a holding area without being started??? Al
Burning Brakes
Joined: Feb 2006
Posts: 1,223
Likes: 4
From: Regina Saskatchewan
Well I happen to fog my engine when I put it away. I don't consider it a waste of time. For those of you that think it is ,are you measuring the amount of wear that occurs when you start it? Sure you've "started it that way for 4 years". Big deal. A can is $4.50 and it last me 4 years. I say cheap insurance . Those of us with boats do it for 6 months -no questions asked! Why wouldn't we do it for our C3s. Take off your tin foil hats and spend $1 / year.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 27
From: Florida
We winterize we over 300 boats a year, most all are 4 stroke. We only fog the engines of boats which are to be shrink wrapped, which are very few for us. We store just about every boat inside. In fact, new EFI with Catalytic convertes can not be fogged, or damage can be done by the foggin oil. It can also coat the MAP sensor's which can send an incorrect signal to the ECM. As for the Vette, I do not fog at all, as for our snowmobiles, we don't fog them either any more. I believe if you are going to store the engine for longer than 6 to 7 months fog it, but for normal storage, no real reason to. How long do cars set on a lot or a holding area without being started??? Al
Well I happen to fog my engine when I put it away. I don't consider it a waste of time. For those of you that think it is ,are you measuring the amount of wear that occurs when you start it? Sure you've "started it that way for 4 years". Big deal. A can is $4.50 and it last me 4 years. I say cheap insurance . Those of us with boats do it for 6 months -no questions asked! Why wouldn't we do it for our C3s. Take off your tin foil hats and spend $1 / year.
Safety Car
Joined: Sep 1999
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From: AnyTown NJ
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
After over 10 years of corvette ownership I've never fogged my engine and have never had an issue starting the car in the spring.....I guess the question is based on my experience why do something that's not necessary.
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
I don't think it is a matter of the car not starting it is the wear that occurs when you do start it after sitting that long. The fogging oil coats everything including the cylinder walls with an oil that keeps moisture from doing damage and helps everything on start-up.
It could be that most folks start their cars several times during the winter where you never start your boat until you are ready to use it again.
It could be that most folks start their cars several times during the winter where you never start your boat until you are ready to use it again.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
Well I happen to fog my engine when I put it away. I don't consider it a waste of time. For those of you that think it is ,are you measuring the amount of wear that occurs when you start it? Sure you've "started it that way for 4 years". Big deal. A can is $4.50 and it last me 4 years. I say cheap insurance . Those of us with boats do it for 6 months -no questions asked! Why wouldn't we do it for our C3s. Take off your tin foil hats and spend $1 / year.
None has ever been fogged. All run perfectly. Fogging the engine simply prevents the rings from sticking to the cylinder walls, nothing to do with lubrication.
No tin foil hats here.
Safety Car
Joined: Sep 1999
Posts: 4,930
Likes: 11
From: AnyTown NJ
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Well since I'm talking about a fairly large sample of time and the fact my car uses/burns no oil during the year you'd be hard pressed to convince or prove to me there is any significant wear occurring during my spring startup.
BTW, I don't start my car during winter storage....that's probably the worst thing you could do.
If your happy fogging your engine every fall knock yourself out....again from my experience it's not necessary.
BTW, I don't start my car during winter storage....that's probably the worst thing you could do.
If your happy fogging your engine every fall knock yourself out....again from my experience it's not necessary.
CF Community Team
Joined: Oct 2004
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From: Cape Cod, Mass.
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I have never "fogged" the engines in my Corvettes and never had an issue. I have had my 65 for 40 years with no issues. Of course I try to drive them as weather and road conditions allow, but there have been nasty winters when the cars sit for prolonged periods.
I also have a Donzi (boat). It has a fuel injected 350. I don't fog that either. I change the oil, change the outdrive lube, drain the block, fill with anti freeze, fill the gas tank and pull the battery. It fires right up in the Spring with NO SMOKE SHOW and no fouled plugs.
I also have a Donzi (boat). It has a fuel injected 350. I don't fog that either. I change the oil, change the outdrive lube, drain the block, fill with anti freeze, fill the gas tank and pull the battery. It fires right up in the Spring with NO SMOKE SHOW and no fouled plugs.
Melting Slicks
Joined: Aug 2004
Posts: 2,220
Likes: 6
From: www.Z16.org North/West Pennsylvania
I've been storing cars for the winter for over 30 years and my opinion is that length of time in storage and dampness of the storage area determine weather fogging is necessary. In a heated garage for 6 month storage I think fogging isn't necessary. Storing a car in a dirt floor, unheated garage for 6 months or longer I would definitely fog it. 
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,112
From: Crossville TN
If a boat, car, snowmobile, etc. will be stored in an open environment near water for the winter, fogging is beneficial. If any of the above are stored inside and in a non-damp environment, its a waste of time.
However, unless it is detrimental to the emissions system or engine control system, fogging can't really hurt anything.
However, unless it is detrimental to the emissions system or engine control system, fogging can't really hurt anything.