Sea foam for outboards?

brodmann

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Oh, this is always a fun one!!! One man's product of choice makes him a complete idiot in the eyes of another guy!!
I'll join in. In the mid 70's, I worked as a teenager at a service station. You know, pull up, "ding, ding", "fill 'er up and check the oil sir?" Yeah, that was me. We cleaned up carbon by running a motor at about 1,500 RPM's and slowly pouring automatic transmission fluid directly into the carburetor! It would pour out black smoke, and we told customers that was burning the carbon out! We also told them it would smoke like that the next couple of times that they cranked it up in the morning. I have no idea if that helped/hurt an automobile, but it was common practice and customers felt that we were really helping them out. There weren't very many "fix in a can" products back then. There was STP and Marvel Mystery Oil that I remember. STP was "The Racers Edge", so that would make your car a race car I guess! And Marvel Mystery Oil, was some type of magical VooDoo potion! Things have changed. Or, have they??
 

jimmbo

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We cleaned up carbon by running a motor at about 1,500 RPM's and slowly pouring automatic transmission fluid directly into the carburetor! It would pour out black smoke, and we told customers that was burning the carbon out! We also told them it would smoke like that the next couple of times that they cranked it up in the morning. I have no idea if that helped/hurt an automobile, but it was common practice and customers felt that we were really helping them out. There weren't very many "fix in a can" products back then. There was STP and Marvel Mystery Oil that I remember. STP was "The Racers Edge", so that would make your car a race car I guess! And Marvel Mystery Oil, was some type of magical VooDoo potion! Things have changed. Or, have they??
It was certainly making all the Carbon that was being expelled. Whether or not ATF is good Solvent, I can't say I have ever seen any shop using it as a Parts Soak, except for new Clutch Plates/Bands for Auto Transmission rebuilds.
I heard of people putting a couple of Cans of ATF into the Crankcase, to "clean/flush" the engine. I also heard of wiped Cam Lobes after such "Cleanings".
STP... On a worn old Smoker, it would make more sense to just use a higher Viscosity Oil, like 20-50, in the first place, than to use 5W-30 and a can of Honey, which as a Viscosity Index Improver, really offered no improvements to Lubrication.
One Oil Additive that I thought was actually useful, was GM's EOS(Engine Oil Supplement). It contained some Detergents, and an Extreme Pressure Additive to protect Cam Lobes during Break In.

I have watched videos of people spraying Seafoam in to outboards, and then exclaiming all the Carbon/Guck that was in the Water after. Well, the SeaFoam is what made that Carb/Guck, itself being burnt. Adding too much Oil to the Gas also makes for a lot of Carbon/Guck in the water.
I suspect the better TCW-3 Oils themselves, probably do a better Job at Cleaning than a lot of the Snake Oils
 
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Phil Rudd

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Sep 11, 2022
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Random question has anyone used sea foam or another guess additive in their fuel to keep it stable and to clean motor? I have a Johnson 110 1987... And I was just curious if anyone thought that was a good idea or bad one...
Sea Foam was developed originally for 2 stroke out board motors. I’ve used in both 2 stroke and 4 stroke motors.
 

tphoyt

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I used ATF down the carb throat for a stuck lifter once on old Thunderbird and it worked great.
Then I used Marvels Mystery Oil in my 65 Riviera and 2 weeks later had broken rings on 2 pistons.
Ya just never know. Remember when Slick 50 took the world over.
 

jimmbo

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I used ATF down the carb throat for a stuck lifter once on old Thunderbird and it worked great.
Then I used Marvels Mystery Oil in my 65 Riviera and 2 weeks later had broken rings on 2 pistons.
Ya just never know. Remember when Slick 50 took the world over.
I didn't realize that the Lifters were accessible via the Induction System. I guess I learned something New today...
I remember a bunch of lawsuits against Slick 50 over damaged Engines
 

tphoyt

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Honestly Jimmbo I never really understood it myself but an old timer told me to try it so I did and it worked and I never had a problem again. It’s to bad he wasn’t there to stop me from using the Marvels. 😂
 

jimmbo

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You may have a slightly sticky Valve, and there was some Lash in the Valve Train. There is no connection between the Lifters and and Induction System
 

tphoyt

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When you put it like that it all makes sense. This happened nearly 40 years ago and I never really put that much thought into until today.
 

airshot

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Mostly Naphtha and Kerosene with some very very low Viscosity Oil. I wouldn't use it if I was paid too.
That is why there are many products out there to use. Another one that I have had excellent sucess with is the Lucas brand fuel conditioner. Doesn't work as well on two strokes but awesome for four stroke engines. Seafoam for two strokes and lucas for 4 stroke engines!! After 30 plus years of regular use and O issues, I am very confident in my choices, however, I am sure there are others that people have used and had good sucess with.
 

Phil Rudd

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Sorry Jimmbo, I just googled it. Apparently Canada does not have any ethanol free available.
 

jimmbo

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Sorry Jimmbo, I just googled it. Apparently Canada does not have any ethanol free available.
Yeah, the Corn Farmers Lobby hoodwinked the Government into thinking Ethanol is good for Cars/Trucks.
 

salvageyard saviour

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Tried the Marvel ring soak on a 99' Saturn 4 banger. The stuff was impossible to get back out and blew the ceramics on all 4 plugs. Lucky to have not bent a rod or blown head gasket. Hydrolock.

My favorite decarboning cylinder cleaner is a slow spray of water into a revving intake. 4 stroke only.

Used Sea Foam in gas for some varnished sticking intake valves after using very old bad gas in my small engines.

My big outboards have only used Stabil for storage. Smokes a bit extra in the spring.
 
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racerone

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Dec 28, 2013
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A lot of this stuff is on the shelf because folks buy it.-----Not every consumer knows how engines work,----How parts work.----Where parts are in an engine.-----No different the medicines / potions / treatments for the human body.----Folks are desperate and hope for a cure !!
 
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