Seafoam in oil to clean crankcase?

[AP9]

I'd like to keep this vehicle running as long as possible. I've never had any engine problems, and I'd like to keep it that way for as long as possible.

I've read about putting Seafoam in the engine oil to clean sludge out of the crankcase. The general consensus seems to be that this is acceptable, but the oil should be changed shortly thereafter.

People also seem to have concerns about running transmission flushes on high-mileage vehicles as this could cause garbage in the transmission to get stuck in solenoids, valves, etc. Well I certainly wouldn't want to remove sludge or deposits from cylinder walls or the bottom of the pan or somewhere else where they're not really harming much, just to have them get stuck in oil passages and actually start to cause problems.

What would be the ideal amount to add? I'm thinking I'll probably add some Seafoam and replace the oil filter with a new cheap one, then change the oil and filter (using a good filter this time) within a day or a few miles.

The vehicle has been well-maintained mostly, but about 1-2 years ago there was a period which I went almost a year and a half & about 5000 or so miles without an oil change (for several months of that, vehicle was in storage / almost never driven). Since then I've been very diligent about changing oil, and it's appeared fairly clean. I am not burning any oil though I do have a slight leak at the rear crankshaft seal.

So does my plan sound problematic at all? Any other suggestions or concerns?

 

[littlezell]

I would try it......might clean it up really good....hell I know it does a good job cleaning the uper half..

 

[rjcooperss396]

If you've changed the oil frequently there is no reason to run Sea Foam in your oil. I changed the oil on my Cobra every 4000-5000 miles and when I pulled the engine to rebuild it there wasn't any oil buildup. For reference, my Cobra had a supercharged 302 that put down 430rwhp on pump gas and 470rwhp on race fuel and it was drag raced, road raced, autocrossed and daily driven and had 90,000 miles on it.

 

[AP9]

I'm just still a little concerned about the one time I had gone almost a year and a half / 5000+ miles without changing oil. Had it done by a local mechanic that time (which was a little less than a year ago) and he said the oil looked really bad.

 

[rjcooperss396]

My Chevelle which I drag race has been sitting for almost a year and a half in my garage because I broke the trans and the oil still looks good. Having the truck sit for a year would not make the oil dirty.

I have run Sea Foam in the crank case on my Explorer back when it had the 4.0 in it and it didn't do any harm (meaning it didn't cause a rod knock or anything) but I never pulled the engine apart to see how it looked inside. I sold it complete to a guy who installed it in his Ranger. I added the recommended amount which I think was about a quarter of the bottle or something like that and drove with it for around 500 miles. Then I had the oil changed.

 

[mr_valingo]

My oil looked clean. Dumped a whole can into my motor warm and ran it for a half hour. Oil was black that came out. Put in cheap Walmart full synthetic with a napa gold filter and ran it for 1500 miles. Now im back to castrol for 7000 miles and even if i put more seafoam in she still comes out clean

 

[koda2000]

I'm probably gonna catch a lot of flack for my opinion, and I can probably guess at who on this forum will argue the most, but I think SeaFoam (and products like it) are "snake oil". If you use quality oil and filters, and change them regularly, at 3-month/4000-5000 mile intervals, you shouldn't have sludge in your engine. Missing one scheduled oil change shouldn't make much difference. In my family's vehicles (all of which I maintain) I've never found any sludge when making repairs to seals & gaskets. If you're engine has sludge in it, breaking it loose can clog your oil pump's pickup screen and then your engine will loose oil pressure and wipeout the bearings in a hearbeat.

As far is running SeaFoam through your intake, have you ever seen the amount of oily carbon buildup there is in a high mileage intake? it's a lot, and running a few ounces of some magic potion through an intake for 15 minutes isn't going to make it go away. it'll sure smoke up your neighborhood though...

As far as flushing your trans, the only particulate substance that builds up in your transmission is fine metal filings and clutch-plate material (clutch packs and gears wear, it's just the way it is, eventually they wear out) the trans filter and pan magnets catch most if that. Trans fluid is a super-high detergent lubricant. It's designed to keep your transmission sparkling clean. You should change your trans filter and replace some of the fluid every 30-40K, or if it smells burn and/or is not bright pink in color. Unless you've cooked your trans fluid, by heavy towing or aggressive driving, flushing just isn't necessary and can do more harm than good, especially when parts are reaching the end of their service life.

If you service your vehicle regularly, use quality products and drive gently it should last a long time. Getting 300K out of modern vehicles should be totally realistic, but you can't make up for 200K of previous neglect.

These are my opinions, but they are opinions formed over 50 years of working on vehicles.

 

[mr_valingo]

I bought my x from a girl who owned it for about 6 years and did maybe 3 oil changes in that time. I saw results from the seafoam and i know guys who dump tranny fluid in the oil to clean things up. Fact is, oil breaks down. It can cause buildup even if you change the oil frequently. I few years at a quicklube sure proved that

 

[Flash]

@koda2000. I've read a lot of your posts and I respect your opinion.
I have to ask why you think Seafoam is snake oil.
Is it because you think it doesn't fulfill it's intended function or is just because you think that a well maintained engine doesn't need to be cleaned out?
Or that the manufacturers are just selling a cure for fear?

I haven't used the brand Seafoam but I have used other products chemically similar and now use my own formulation and I can guarantee to you that they do work.
It's a fact of life that combustion chambers, ring lands and valves get coked up especially if a bit more oil is slipping past the oil control ring than it should.

Seafoam like products do actually decoke the upper cylinder and will allow the engine to run properly if there was a build up causing a problem.

I doubt my crankcase needs any flushing, any engine of mine I've opened up has never had sludge in it except for a BMW that blew a head gasket and filled the crank and radiator with chocolate milk.
I used a mixture of cheap, thin oil and kerosene to clean that out. it seemed to work well.

Clutch fibres can build up and clog a transmission valve body. Bad maintenance and overheating causes that.
Unless the transmission is really horrible inside I would only recommend a flush with clean fluid but I'd also recommend preventative maintenance and the addition of an accessory spin on filter and an additional trans cooler.

So, I'd only use a flush in the engine or trans if it was really disgusting and then I'd be prepared for things to go wrong after that. But consider this; a chunk of sludge could break off anytime and block a gallery anyway, if you've used a chemical to dissolve the sludge correctly then it should flow through the galleries properly.

I know a bloke who drains the oil from the 360 engine in his Chrysler then refills the crank with diesel, runs that for a few minutes then dumps it and refills with oil.
It doesn't seem to have hurt the engine but I wouldn't do it and if the insides of my engines is any testimony I don't need to.

 

[koda2000]

Flash: I just don't think using additives (like Seafoam or Lucas, to name two very popular additives) is necessary. Some people swear by them. I don't think it hurts anything, it just shouldn't be necessary on a well maintained engine. I've had the engines apart on nearly all of my hi-mileage vehicles (usually to replace gaskets or seals) and have never found any sludge. Most of these vehicles I bought new and they've never seen the inside of a repair shop, as i do all my own maintenance and repairs. in 50 years (and more vehicles than I can remember) I've never had an oil related failure of any kind. I have used Halvoline, Castrol, Valvoline and most recently Motorcraft Synthetic Blend oils and quality filters (Motorcraft, Wix, NAPA Gold) changing both at around 3,000 miles. I don't think there is any doubt that synthetic oils protect better then conventional oils, for that reason I've extended my oil changes to $5,000 miles.

The biggest enemy of automatic transmission fluid is heat. External coolers certainly help to keep the temps down. An external filter is also a great idea, as it's easily changed. Many years ago manufacturers stopped putting drain plugs in trans pans so that you were encouraged to change the filter with the fluid (and to save a buck I suspect). I usually add a drain plug to make draining the fluid much less messy.

Again, these are my opinions based on my experiences. As I said, I expect many will disagree with me. If it gives someone piece of mind to use additives, then they should do so.

 

[Flash]

I agree with everything you said there.
Nothing beats not having to use an additive because you've kept up with the maintenance.

Additives are not a good replacement for maintenance.

I do think an engine can benefit from an upper cylinder clean out once in a while.
I cleaned out my 2.0 litre Mondeo (Contour) using my own concoction in an attempt to cure a problem that turned out to be a faulty timing belt tensioner.
When I pulled the head off a month later to replace the head gasket I could see the machine marks on the tops of the pistons and read the number stamped on them.
There was no carbon to be scraped of the pistons or the valves.

It's not something that has to be done often though.

 

[JohnnyO]

If the oil is relatively clean then I wouldn't worry about it. I have used a product called Auto-RX on used vehicles that I've bought used and I like it a lot. If the vehicle has been sitting a while it is good to change the oil because of condensation inside the engine. Coolant too because even if it isn't flowing it will still build up electrolysis from dissimilar metals.

www.auto-rx.com

 

[AP9]

Thanks all for your input. I certainly don't want to put anything in that is going to cause further problems, but on the other hand I am willing to do whatever it takes to keep the vehicle running healthy for as long as possible.

 

[littlezell]

I'm probably gonna catch a lot of flack for my opinion, and I can probably guess at who on this forum will argue the most, but I think SeaFoam (and products like it) are "snake oil". If you use quality oil and filters, and change them regularly, at 3-month/4000-5000 mile intervals, you shouldn't have sludge in your engine. Missing one scheduled oil change shouldn't make much difference. In my family's vehicles (all of which I maintain) I've never found any sludge when making repairs to seals & gaskets. If you're engine has sludge in it, breaking it loose can clog your oil pump's pickup screen and then your engine will loose oil pressure and wipeout the bearings in a hearbeat.

As far is running SeaFoam through your intake, have you ever seen the amount of oily carbon buildup there is in a high mileage intake? it's a lot, and running a few ounces of some magic potion through an intake for 15 minutes isn't going to make it go away. it'll sure smoke up your neighborhood though...

As far as flushing your trans, the only particulate substance that builds up in your transmission is fine metal filings and clutch-plate material (clutch packs and gears wear, it's just the way it is, eventually they wear out) the trans filter and pan magnets catch most if that. Trans fluid is a super-high detergent lubricant. It's designed to keep your transmission sparkling clean. You should change your trans filter and replace some of the fluid every 30-40K, or if it smells burn and/or is not bright pink in color. Unless you've cooked your trans fluid, by heavy towing or aggressive driving, flushing just isn't necessary and can do more harm than good, especially when parts are reaching the end of their service life.

If you service your vehicle regularly, use quality products and drive gently it should last a long time. Getting 300K out of modern vehicles should be totally realistic, but you can't make up for 200K of previous neglect.

These are my opinions, but they are opinions formed over 50 years of working on vehicles.

I would soo agree with you on this... this is what I have learned working in shops over the past years and going to school along with person experience myself... I helped change a 3.1 out of a 96 chebby car and the guy had ran mobil one since new. it looked very clean inside like it was brand new, yet it had 350,000 on it.

 

[my98nnj]

I'm probably gonna catch a lot of flack for my opinion, and I can probably guess at who on this forum will argue the most, but I think SeaFoam (and products like it) are "snake oil". If you use quality oil and filters, and change them regularly, at 3-month/4000-5000 mile intervals, you shouldn't have sludge in your engine.

Best advise is right there. Today's engine oils have plenty of detergents in them to keep the crank case clean. Hanse, the only thing that should be in your crank case is engine oil.

Don't fall for marketing nonsense.

 

[ponkotsu]

I'm probably gonna catch a lot of flack for my opinion, and I can probably guess at who on this forum will argue the most, but I think SeaFoam (and products like it) are "snake oil". If you use quality oil and filters, and change them regularly, at 3-month/4000-5000 mile intervals, you shouldn't have sludge in your engine. Missing one scheduled oil change shouldn't make much difference. In my family's vehicles (all of which I maintain) I've never found any sludge when making repairs to seals & gaskets. If you're engine has sludge in it, breaking it loose can clog your oil pump's pickup screen and then your engine will loose oil pressure and wipeout the bearings in a hearbeat.

As far is running SeaFoam through your intake, have you ever seen the amount of oily carbon buildup there is in a high mileage intake? it's a lot, and running a few ounces of some magic potion through an intake for 15 minutes isn't going to make it go away. it'll sure smoke up your neighborhood though...

As far as flushing your trans, the only particulate substance that builds up in your transmission is fine metal filings and clutch-plate material (clutch packs and gears wear, it's just the way it is, eventually they wear out) the trans filter and pan magnets catch most if that. Trans fluid is a super-high detergent lubricant. It's designed to keep your transmission sparkling clean. You should change your trans filter and replace some of the fluid every 30-40K, or if it smells burn and/or is not bright pink in color. Unless you've cooked your trans fluid, by heavy towing or aggressive driving, flushing just isn't necessary and can do more harm than good, especially when parts are reaching the end of their service life.

If you service your vehicle regularly, use quality products and drive gently it should last a long time. Getting 300K out of modern vehicles should be totally realistic, but you can't make up for 200K of previous neglect.

These are my opinions, but they are opinions formed over 50 years of working on vehicles.

I agree with you. I'm an engineer, so I base my decisions on facts and test data whenever possible. Seems like the vast majority of these magic chemicals are basing their claims on opinion. Occasionally you will see some real testing done on something, and almost invariably it turns out to be useless, or such a small improvement that its difficult to even measure. If they did do some empirical testing, and it showed a big improvement, you can bet they would have the data all over the can. But they don't, so I suspect there was no testing, or the testing showed it to be worthless.

I've rebuilt engines before. It takes a lot of time and work to remove deposits and varnish from the inside of an engine, intake, carb, etc. In some cases you literally need a hammer and chisel. There's just no way some chemical is going to magically make it vanish. And even if it did remove big chunks, I would be more concerned about that stuff getting stuck somewhere else that would cause more damage.

 

[koda2000]

I agree with you. I'm an engineer, so I base my decisions on facts and test data whenever possible. Seems like the vast majority of these magic chemicals are basing their claims on opinion. Occasionally you will see some real testing done on something, and almost invariably it turns out to be useless, or such a small improvement that its difficult to even measure. If they did do some empirical testing, and it showed a big improvement, you can bet they would have the data all over the can. But they don't, so I suspect there was no testing, or the testing showed it to be worthless.

I've rebuilt engines before. It takes a lot of time and work to remove deposits and varnish from the inside of an engine, intake, carb, etc. In some cases you literally need a hammer and chisel. There's just no way some chemical is going to magically make it vanish. And even if it did remove big chunks, I would be more concerned about that stuff getting stuck somewhere else that would cause more damage.

i couldn't agree with you more. another example of opinion over science is Royal Purple products. Horse Power TV took a vehicle and chassis dyno'd it, then replaced all the oils with Royal Purple products and re-dyno'd the same vehicle to see what improvement were achieved. turns out horse power and fuel economy actually decreased, yet people continue to shell out twice the price of conventional brands because they think Royal Purple is a superior product.

 

[Flash]

Personally I'd **** myself if I opened one of my engines to find that it was in a state where it needed any desludging.

 

[AP9]

I agree with you. I'm an engineer, so I base my decisions on facts and test data whenever possible. Seems like the vast majority of these magic chemicals are basing their claims on opinion. Occasionally you will see some real testing done on something, and almost invariably it turns out to be useless, or such a small improvement that its difficult to even measure. If they did do some empirical testing, and it showed a big improvement, you can bet they would have the data all over the can. But they don't, so I suspect there was no testing, or the testing showed it to be worthless.

Reminds me of these Google ads I've been getting ever since I started using this site regularly: "$69 FORD F150 Chip - [website of advertiser] - Gain 60 Horsepower Instantly Instant 4-7 MPG Fuel Savings"
I'd really like to see the validation & testing that led them to jump to THAT conclusion. No way in hell that just leaning the fuel:air ratio out could result in that kind of improvement -- not to mention all the extra NOx it'll be spewing out.

And even if it did remove big chunks, I would be more concerned about that stuff getting stuck somewhere else that would cause more damage.

That's my main concern. If I waste a few dollars on snake oil, not the end of the world, just as long as it doesn't actually HARM anything.

 

[don-ohio]

AP9.......this is the way I do it. Sea-Foam is fine to clean èr out,but what I use it for is high mileage or seldom use vehicles,or vehicles which never get the `carbon blown out'of them.LOL!
Just wait until you're near oil change time,within 50 miles and add the 1/2 can to your crankcase. If you have any stuck rings or sludge,it will move it out.
Change the oil with full synthetic(I use Pennzoil Platinum or Castrol Syntec)and put on a high quality filter.
I've never had a problem doing this,and I've freed some sticking rings this way.
As far as flushing a transmission with clean fluid,it isn't going to hurt anything.
don-ohio ^)