P3x 56 #1 Posted March 25 Got a couple of cans of High Mileage Sea Foam to put in my truck's Fuel and Oil System. Only drive it about 350-400 miles a year and figured it most likely could use a good internal cleaning. Always add regular Sea Foam to my 310, 520, and Honda Lawn Mowers fuel and thinking about adding it to the horses oil, run for a while before changing the oil. To date can only rely on a time I added regular Sea Foam to Honda's oil. Its air intake system design is plagued with mass quantity's of dirt and dust entering the Air Filter Box with normal use around my yard. Was losing RPMs constantly so started cleaning the air filters and box with compressed air after every use. Would run better but eventually ran crappier later each season needing to clean the carb. One time I figured I'd pull the plug and check the piston and cylinder condition - both were pretty dirty. I added regular Sea Foam to the oil per the instructions on the can to see what it would do. Ran it during ts regular mowing (about 45 mins). Pulled the spark plug to check the result and was quite pleased; It did better than I thought. The Cyl. walls were clean to the point of being able to see scoring with all dirt removed from the top of the piston which was back to shiny aluminum. I use the 520 as a dedicated snow throwing machine so it does not receive much use. Several years ago I cleaned the Onan's Cyl. Head components and would like to prevent the getting gunked up from lack of use. I do start and run it every now and then but am thinking about adding Sea Foam to the oil. Did a search to find if anyone has added Sea Foam to their Onan's oil and what the result was.. I've always been skeptical about adding anything to an engine's oil. The Honda I did not care too much about and ended up with good results. Just added it to my truck's oil and will start driving it more to get 250-300 miles then change the oil and inspect the cylinders. I'ts a beater so no loss there. But would hate to add it to the horses and end up with a loss of compression or leaks. All input appreciated! 2 Share this post Link to post Share on other sites
ebinmaine 67,424 #2 Posted March 25 I'll be curious to see the other answers. I personally am among the NO ADDITIVES folk. No Sea foam No Stabil NO cleaners And IMHO most importantly NON ETHANOL GAS That said..... In the interest of full disclosure. I HAVE used a Seafoam brand "tune-up in a can" on engines for friends that didn't want to pay for a proper carb clean. For the record... I was impressed with the results. Would I add ANY cleaner to the OIL of a tractor? I'm open minded but I don't see either happening here. Share this post Link to post Share on other sites
squonk 41,068 #3 Posted March 25 (edited) Sea Foam works. I don't care what any of the naysayers say. I have personally seen it FIX 4 engines. I had a 94 Chevy truck with a lifter tick. It had been there for over a year. I was working at Napa and the Sea Foam rep was there. I got talking to him and he hands me a can. Says pour half of it into the oil. I dove home for lunch ( 3 miles ) Went back to work and the tick was gone and stayed gone. Wife's Dodge Caravan. Pinged like crazy. Ran Sea Foam into the intake and soaked the pistons. Ping gone. B- I -L had a Buick 4 banger that rattled and clanged like it was ready to blow up. Half a can into the oil and the other half down the intake. Ran like new. 1990 520. Onan surged like crazy. Treated the gas in the tank and soaked the pistons. Surge disappeared. Edited March 25 by squonk 2 3 Share this post Link to post Share on other sites
P3x 56 #4 Posted March 25 Ya, I'm not looking to use it to "fix" anything, as all are running fine. Just thinking of adding as a preventative measure to little used tractors/vehicles. It did clean the internals well on the Honda mower I added it to. With Onans a little more complex than a one cylinder Honda, I'm a bit hesitant. Maybe I'll wait until I get some miles on my truck and see how that comes out. Thanks for the replies. 1 Share this post Link to post Share on other sites
elcamino/wheelhorse 9,297 #5 Posted March 25 I use Sea Foam in gas for everything i have . Never put in the oil but every time I fill the tank on the horses they get some. Truck and car get some in the tank as per instructions about every 3 months. 2 Share this post Link to post Share on other sites
rmaynard 15,434 #6 Posted March 25 I know that my opinion on this subject is not shared by all, but those who agree with me, agree wholeheartedly. Here's the reason why. Seafoam is a mixture of: Pale Oil 60% (Pale oil is straight naphthenic mineral oil) Naphtha 25% (Same as mineral spirits paint thinner, only evaporates faster) IPA 15% Isopropanol (Isopropyl alcohol). If these cheap and readily available ingredients did anything to improve the performance of either oil or gasoline, don't you think the refineries would include them in their products? As of my last research on Seafoam, I haven't found any oil or gas companies that recommend putting them into their products. 1 Share this post Link to post Share on other sites
Achto 27,565 #7 Posted March 25 38 minutes ago, P3x said: With Onans a little more complex than a one cylinder Honda, I'm a bit hesitant. An Onan is an engine - it goes suck, squish, bang, blow just like every other internal combustion engine. No more complexed that an apposed cylinder Briggs or Kohler. I am not a big advocate of any "snake oil cure in a can", except for SeaFoam. It does every thing that it advertises. Some of my friends call it "Dan in a can" I add 1oz per gallon of gas to all my small engine gas, works well as a stabilizer and it keeps the fuel system clean. I also add it to the oil system on grungy engines, run it for an hour or 2 then do an oil change. Cleans thing up nice. 2 1 Share this post Link to post Share on other sites
Lagersolut 649 #8 Posted March 26 I've been adding Stabil ( because my gas sits 6 months ) and 2oz of Marvel( per 5gal can ) for a little lube on the top end for almost 30 years - knock on wood my engines have treated me well with little or no issues. Always non Ethanol in my old and small stuff . 2 Share this post Link to post Share on other sites
RED-Z06 2,221 #9 Posted March 26 Seafoam isnt bad. The only additive i really like is Chevron Techron fuel system cleaner, GM recommends it and only it for varnished fuel senders and it works 2 Share this post Link to post Share on other sites
lynnmor 7,305 #10 Posted March 26 I put gasoline with 10% or less ethanol in the fuel tank and motor oil with a SM or lower rating in the crankcase. That has worked for me over many thousands of Onan hours. Fuel that will be stored for months I treat with Stabil. I would not add powerful solvents to any engine unless I want to treat a real issue and am willing to take a chance of harm. Actually you can read the owners manual and basically it will tell you the same thing. Share this post Link to post Share on other sites
P3x 56 #11 Posted March 26 My use of "complex" was to compare its build configuration vs. a one Cyl. Honda - two Cyls, 4 Valves, oil press. Sw., etc., plus more gasketed areas that could develop leakage by introducing Sea Foam. As far as recips go, this is what I consider complex! 3 2 Share this post Link to post Share on other sites
JoeM 7,873 #12 Posted March 26 13 hours ago, Achto said: it goes suck, squish, bang, blow just like every other Maybe a reenactment video of you doing that combo is in order..........so we can make sure of the sequence I know some additives will clean. I have used the Chevron Techron with good results. Also, think more is not better. Using and excessive amount of these additives will degrade systems. In the tractors, just plain old non E fuel and good motor oil has been the ticket. I believe most of the time a lot of products do very little and just simply make you fill better. 2 1 Share this post Link to post Share on other sites
ebinmaine 67,424 #13 Posted March 26 1 minute ago, JoeM said: Maybe a reenactment video of you doing that combo is in order..........so we can make sure of the sequence 1 Share this post Link to post Share on other sites
rmaynard 15,434 #14 Posted March 26 23 minutes ago, JoeM said: I have used the Chevron Techron with good results... to my point, Techron is an additive that Chevron puts in their gas and also sells over the counter. I've yet to see anything like this - "Shell Gas/Oil, Now With Seafoam" 1 Share this post Link to post Share on other sites
JoeM 7,873 #15 Posted March 26 15 minutes ago, rmaynard said: to my point, Techron is an additive that Chevron puts in their gas and also sells over the counter. Don't know the concentration in their fuel? I do know it will clean injectors when added to the fuel tank. My son had a S10 four cylinder. He experienced a problem with injectors sticking open. After a couple episodes, the Chevy garage advised using Techron. No more issues. Put a bottle in once a year. I am still not a big additive person but it worked in S10 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #16 Posted March 26 I had a Murray mower that had sat for years with gas in it, tank was full of black goo, line was black goo, carb was solid hard black goo that repelled carb cleaner. I put on a new line, flushed the tank enough that fuel flowed somewhat...then dumped in a bottle of seafoam and about a quart of gas. I let it simmer hooked up to the carb for a couple days; pulled the tank and dumped out a now loose black sludge, blew out the new hose, and dropped the carb bowl.. the bowl had about an inch if black in it but, it was pourable and fuel ran from the needle. I blew it out with air and it ran...after a couple hours of fiddling it ran good. 1 Share this post Link to post Share on other sites
rmaynard 15,434 #17 Posted March 26 10 minutes ago, RED-Z06 said: I had a Murray mower that had sat for years with gas in it, tank was full of black goo, line was black goo, carb was solid hard black goo that repelled carb cleaner. I put on a new line, flushed the tank enough that fuel flowed somewhat...then dumped in a bottle of seafoam and about a quart of gas. I let it simmer hooked up to the carb for a couple days; pulled the tank and dumped out a now loose black sludge, blew out the new hose, and dropped the carb bowl.. the bowl had about an inch if black in it but, it was pourable and fuel ran from the needle. I blew it out with air and it ran...after a couple hours of fiddling it ran good. Probably could have done the same thing with fresh gas for a lot less money. Share this post Link to post Share on other sites
RED-Z06 2,221 #18 Posted March 26 13 minutes ago, rmaynard said: Probably could have done the same thing with fresh gas for a lot less money. A straight gas soak has never really done much for black varnish, even my hot tank wont touch it, seafoam and gas dissolves it though, haven't tried other additives yet, but seafoam works on the rare instances I come across the stuff. I dont usually bother with cleaning unless the carb is obscenely priced or in the case of that Tecumseh, discontinued. 1 Share this post Link to post Share on other sites
rmaynard 15,434 #19 Posted March 26 I soak carbs in lacquer thinner. 3 Share this post Link to post Share on other sites
RED-Z06 2,221 #20 Posted March 26 1 hour ago, rmaynard said: I soak carbs in lacquer thinner. It works as long as theres no plastic bits. Some modern carbs are 98% plastic, while others have a permanently installed plastic float pin mount and seat. Share this post Link to post Share on other sites
kpinnc 12,005 #21 Posted March 26 (edited) Seafoam and similar will obviously never fix a mechanical issue. But- removing carbon and sludge can most definitely be accomplished with it. Using Seafoam regularly in fuel will help against the fuel system getting gummed up, so long as ethanol fuel isn't used. It is especially good at removing carbon buildup in the top end. But Seafoam contains isopropyl, it actually compounds moisture accumulation when used with ethanol fuel. I said all that to say this: when used as intended, additives like Seafoam can be beneficial. But no additive is going to save an engine from a mechanical issue. This discussion is like so many things: without all of the variables, it's hard to know an accurate answer. Most of my tractors sleep in a climate controlled environment, almost never seeing high or low temps. Someone who has no such storage will see more condensation and dust. Humidity here is horrible. Throwing a tarp over something here is actually worse than getting rained on somewhere dryer. In other words, what works here may not work elsewhere. Edited March 26 by kpinnc 2 1 Share this post Link to post Share on other sites
RJ Hamner 1,007 #22 Posted March 26 Simply put: Your mileage may vary. just my $.02 3 Share this post Link to post Share on other sites
ebinmaine 67,424 #23 Posted March 26 6 hours ago, RED-Z06 said: straight gas soak has never really done much for black varnish I've never tried to clean a carb with dark colored varnish in it but I've done a few with a lighter coating. I use an ultrasonic cleaner with straight NON Ethanol gas. I do have to run the more gunkier ones through several cycles of 40 minutes each over the coarse of a week. Share this post Link to post Share on other sites
ebinmaine 67,424 #24 Posted March 26 5 hours ago, rmaynard said: I soak carbs in lacquer thinner. That's something I've been mulling over. Lacquer thinner + ultrasonic cleaner = ?? 1 Share this post Link to post Share on other sites
Wayne0 455 #25 Posted March 26 8 hours ago, JoeM said: Don't know the concentration in their fuel? I do know it will clean injectors when added to the fuel tank. My son had a S10 four cylinder. He experienced a problem with injectors sticking open. After a couple episodes, the Chevy garage advised using Techron. No more issues. Put a bottle in once a year. I am still not a big additive person but it worked in S10 That thing still running? I heard that they come with bearings in the pan. I'm sorry, that was the V-6. Never mind........... Share this post Link to post Share on other sites