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SeaFoam, H6-3.0, Compiled how-to

108K views 121 replies 44 participants last post by  JJutsu 
#1 ·
I finally got around to cleaning my engine with SeaFoam, and once again the H6 is a totally different animal compared to the H4.

What first caught my attention, and caused me to double check all the information on this site, and in the engine service manual. Is that the PCV valve is set up in the reverse order of the H4 engines.

The PCV valve is located on the driver’s side of the engine under the spark plug coil packs, a tube then runs up to the center of the intake manifold, which attaches to a nipple that goes directly into the chamber.

The H4 is opposite of the H6; a tube comes up from the crankcase, which runs to the PVC valve, which screws into the intake manifold, then into the chamber.

So for us often groping in the dark H6 owners, I had the GF snap a couple of pics of the process. Once I assured her that I “probably” wasn’t going to blow anything up that is. lol

Unfortunately, I was not able to convince her to model the process for us. This would have been a much more exciting viewing experience.:12:

(1) First start with a cool engine, pop the hood and remove the Motor cover from your H6 engine. Thanks Peaty!
http://www.scoobymods.com/forums/showthread.php?t=4143

Hopefully, after you properly remove your motor cover, you won’t flip it over only to discover something like this. Yes, I am on my way today to have a few words with the service department manager at my local Subaru smasher dealership. If they ever want my business again, they are going to replace it.

You would think a Subaru trained service technician would know how to properly take off the engine cover. Do they even read the manuals anymore?





(2) Next, never totally trust anyone when it comes to the health of a very expensive piece of equipment. So locate your PCV valve, then trace the gas tube to your intake.





This is where the gas tube enters the intake:



Reference shot:



(3) Now you can begin to SeaFoam your engine. Follow these directions. Thanks Random!

Originally posted by: Random
De-carbonizing combustion chambers and cleaning out intake manifold/ports.
To do this you start the engine cold, and put 1/3 of a can in via the PCV hose, turn off engine, let it sit for 5 min, then start the engine and run till warm (it will smoke when you start it up). Once the engine is warm (after 5 min of idle) you do the same 1/3 of a can while running, then shut off engine and let sit another 5 min. then start engine again (again, it will smoke like crazy at first) then pour remaining 1/3 into pvc while engine is running, and let engine run till it no longer smokes.

[edit] While it is possible, in theory to hydrolock your engine using this method, the trick is to SLOWLY POUR the fluid into the PVC hose via a small funnel. Do NOT allow the engine to "suck" the fluid directly out of the can/bowl via tha hose. YOU should be the one controling the fluid flow, not the engine. You want a very thin stream going in, about pencil lead sized or slighly larger. you don't want a stream as thick as a pencil, that's too fast (unless you're dealing with a LARGE displacement engine). If you pour too fast, the engine will run too rich and die, so you'll know rather quickly. If that happens STOP POURING!!!!! restart engine and let idle 30 second before continuing to pour again, much slower.
Note: The tricky part has always been to feed the SeaFoam into the intake without hydro-locking the engine. But, thanks to a very clever member of this forum, the problem was ingeniously solved. So put away the pride, head down to the local dollar store (before you begin tearing into your engine) and pick up a cheap baby bottle. Thanks jajones480!

Originally posted by: jajones480
I wanted to share how I poured the SeaFoam into the hose. After reading some posts and realizing that we didn't have a funnel small enough I found a good solution. We have a 10 month old little girl and we bought some Dr. Brown's bottles for formula. She stopped using them a long time ago so I decided it was worth a shot. The bottle is 6 ounces with graduated marks and is made of a hard plastic - almost like PVC - and the nipple is silicone. I felt that these would stand up to the solvent better than a traditional #5 plastic bottle. I filled the bottle to about 5.5 ounces and then just attached the free end of the hose to the nipple and let the engine suck it out through the nipple. It worked like a charm and took about 30 - 40 seconds to empty the bottle. The engine didn't hesitate at all and the bottle held up. Hope this works out for other people.
When feeding the SeaFoam to the engine you must keep the bottle nipple a quarter to a half inch away from the manifold nipple. If you let your baby get greedy, it will suck the nipple down, suddenly block off the air flow, and choke itself. (engine will die)

But, you have the key to turn that baby back on, just tease your nipple along its mouth and it will eagerly lap up the goodies.

Sorry couldn’t help it. :p This would have been allot better if the GF had agreed to lean over and do this part for me. :17:

It took a couple of minutes to empty the 5+ OZ from the bottle. You could probably drill a small air hole in the bottle then put the nipple directly in contact with the intake nipple, and it would feed much faster.

But, since this was my first time, and with the fear of hydro-lock in my mind; I went slow and easy.

If you try it faster and it works, please post your results and procedure; if you screw up and hydro-lock your engine, well, that's on you.;)

Please post those results as well, as a lesson learned.:14:

So here are the boring pics of what it should look like:





Note: I didn’t get a lot of smoke while doing this procedure, but I knew that all this stuff had to be going somewhere.

So after the final step, and a good long warm-up; I re-assembled the engine.

Since I-95 is less than a mile from my house. I popped in a White Zombie CD, strapped the GF into the passenger seat, and went for a leisurely engine run-in.

I took it easy till I reached the on-ramp, waited for the entire ramp to be clear, dropped her in 3rd gear, and FLOORED IT!

I must have laid down an eighth of a mile smoke screen! It was awesome! I had the car up to 105 in no time flat. The little hesitation I had before was gone by the time I got home again.

I did this a couple of different times and at different speeds during the run-in, never keeping at one constant speed or RPM, as per a regular break in routine.

Note: As expected after I was all done I had a CEL, but after 3 or 4 startups and shutdowns, the CEL went out. Thanks FMGreen!

Originally posted by: FMGreen
The CEL should go off by itself after about 5 or 6 trips. Mine went off as soon as I started the car for my 5th trip. Your ECM is just freaking out because it was reading an incorrect mixture.
If you don’t feel like waiting for your CEL to go off on its own you can always do this trick. Thanks ivwarrior!

Originally posted by: ivwarrior
Find a auto parts store with a code reader. Usually at the least, the chain stores will have one. Get them to read the code and give you the code number/description. Then have them clear the code. They'll normally do it for free, your mechanic will probably charge you. Drive like normal and wait to see if the light comes back or not.
And now you’re all done. Enjoy!

Warning! If you have children, especially little girls, like I do. After you have completed this process THROW AWAY the baby bottle! It's impossible to hide stuff like this from children, they WILL find it. To eliminate the possibility of your child finding this bottle and playing or drinking from it. GET RID OF IT!

It was only $1.25 It's not worth endangering the health of your child. You have been warned.

Note: No children were poisoned in the making of this tutorial. I am just a very cautious person when it comes to my kid.
 
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#6 ·
Crunch,

My 2008 Limited 4 cyl is set up like your H6 (PCV at the crank case, open nipple on the intake manifold. When I disconnect the PCV hose, the engine sucks are like crazy at the intake manifold nipple and stalls. I assume from reading your post that your engine kept running fine. Does this problem sound familiar at all, or did your engine react completely differently? Did you have to do anything special to keep the engine running.
 
#7 ·
What it IS

One of my obsessions is to know what something is and what it really does and how. SeaFoam is primarily Pale Oil (40 to 60%)[possibly Napthalmic] and Naptha (25 to35%) and Alcohol. There are no detergents.
Does it work or is it snake oil?
I use a fuel additive from Amsoil
 
#79 ·
One of my obsessions is to know what something is and what it really does and how. SeaFoam is primarily Pale Oil (40 to 60%)[possibly Napthalmic] and Naptha (25 to35%) and Alcohol. There are no detergents.
Does it work or is it snake oil?
I use a fuel additive from Amsoil
I ride an 89 Honda GL1500, carbureted, and Seafoam has kept this thing running great. So far I have not had to get into the carbs. When it starts to run a bit rough I pour it into the gas, sometime at a high concentration (I only have a 6 gal tank) and drive. Sometimes starting her up just letting it sit overnight does wonders.

This is true for my previous ride - a GL1200 with 4 carbs.

I also put a can of this in the gas tank of my 98 Legacy 2.2 and that made it run much better. Lost that one to a timing belt BUT until then it was purring along.

I haven't fed it in thru the PCV or manifold but my experience says if there is crap messing up your engine, injectors, plugs, etc. it will get it out.
 
#8 ·
Re: What it IS

Shadow Catcher said:
One of my obsessions is to know what something is and what it really does and how. SeaFoam is primarily Pale Oil (40 to 60%)[possibly Napthalmic] and Naptha (25 to35%) and Alcohol. There are no detergents.
Does it work or is it snake oil?
I use a fuel additive from Amsoil
But those are some pretty handy solvents.... that info come from the MSDS?


Dave
 
#9 ·
MSDS

MSDS sheets will generally tell you what is in something i.e. Armorall has no petroleum distillates which are harmful to rubber, and what the health hazards are of a product, flammability, nastiness etc.
What they will not tell you is the proprietary stuff as long as it does not impact health saftyand environment.
 
#30 ·
I did this to a Honda Civic with 140k miles. By breaking loose all the deposits and gunk that had accumulated over time (my mechanic later told me), this process basically caused my car heart failure. Oil no longer circulated properly, and the engine burned up as I drove down the New Jersey turnpike. What followed was one of the worst days of my life. I would discourage anyone from using this stuff on a car with high miles.
 
#11 ·
Ok so I picked up a can of Seafoam after work and came home determined to try it! I popped my hood, and removed the engine cover, only to realize that my H6 has a slightly different setup from the OP's. The pictures at the top of this thread are apparently from an '02 H6. PCV valve for the '05 is in the same place, but you dont have access to where the hose goes on the intake manifold, so you have to use the end of the hose that connects directly to the pcv valve.

engine shot for reference (cover removed):



pcv valve is on the drivers side valve cover. look for the "finger clamp" where my green arrow is pointing:



I pulled that hose off of the pcv valve and pointed it upwards to insert a small funnel. I had to have my roommate sit in the car and maintain an idle speed to prevent the car from stalling out. did 1/3 bottle, 5 minute rest, 1/3 bottle, 5 minute rest, 1/3 bottle and idled until no smoke.

guess i'll monitor my mpg and see if it helped at all.
 
#12 ·
I would never use this Seafoam stuff. I watched the video on how to "properly" use it, and I have to say that I was horrified by what they recommended. How can something be both a solvent and a lubricant? Aren't these properties diametrically opposed?

Let's assume it's a solvent. When you follow their instructions and dump it into the crankcase, you lower the viscosity of the oil, which seems far more likely to damage things than to help them. Thinned-out oil could damage rod bearings, valvetrain, timing chain, etc.

Let's assume it's a lubricant. Running a lubricant directly through the intake manifold would burn the volatiles in the product and possibly leave behind a whole new set of residues over the old ones. If the volatiles in the Seafoam burn hotter than gasoline, you could roast your valves. And all that crap that is coming out of the exhaust pipe is first flowing past your O2 sensors and catalytic converters, possibly fouling all of them.

Their claim to "encapsulate" water is completely absurd. Any moisture that might be in the crankcase would simply evaporate while the car is running and circulate through the PCV valve into the intake and ultimately out the exhaust. This is part of what the whole PCV system is designed to do all on its own, with or without fuel additives. Moisture in fuel is mainly a problem for cars that sit for long spells without being driven; your daily driver shouldn't have this problem at all.

Oil is a lubricant. Gas is a solvent. They are relegated to different parts of the engine for a reason. Something that claims to do the job of both is either complete BS, or something that will quicken your engine's demise.
 
#13 ·
KarlGustav said:
I would never use this Seafoam stuff. I watched the video on how to "properly" use it, and I have to say that I was horrified by what they recommended. How can something be both a solvent and a lubricant? Aren't these properties diametrically opposed?

Let's assume it's a solvent. When you follow their instructions and dump it into the crankcase, you lower the viscosity of the oil, which seems far more likely to damage things than to help them. Thinned-out oil could damage rod bearings, valvetrain, timing chain, etc.

Let's assume it's a lubricant. Running a lubricant directly through the intake manifold would burn the volatiles in the product and possibly leave behind a whole new set of residues over the old ones. If the volatiles in the Seafoam burn hotter than gasoline, you could roast your valves. And all that crap that is coming out of the exhaust pipe is first flowing past your O2 sensors and catalytic converters, possibly fouling all of them.

Their claim to "encapsulate" water is completely absurd. Any moisture that might be in the crankcase would simply evaporate while the car is running and circulate through the PCV valve into the intake and ultimately out the exhaust. This is part of what the whole PCV system is designed to do all on its own, with or without fuel additives. Moisture in fuel is mainly a problem for cars that sit for long spells without being driven; your daily driver shouldn't have this problem at all.

Oil is a lubricant. Gas is a solvent. They are relegated to different parts of the engine for a reason. Something that claims to do the job of both is either complete BS, or something that will quicken your engine's demise.
Without tipping my hand as to which way I lean, I'd love to hear your take on WD-40.

I'm a good bit skeptical regarding magical elixers, myself.

Dave
 
#15 ·
KarlGustav said:
WD-40 does just what its name implies: it displaces water. It is a lubricant, not a solvent, and it doesn't "encapsulate" water - it just drives it away and leaves oil in its place.

And I wouldn't run WD-40 through my engine, either.
But, it is also about 40% stoddard solvent.

Ideally, the solvent lets it 'run free' into small gaps, then the solvent evaporates, leaving the lubricant.

You can run an engine on WD-40, but it's pretty smoky.


Dave
 
#16 ·
CNY_Dave said:

You can run an engine on WD-40, but it's pretty smoky.
That would be the oil burning off. WD-40 can help dislodge nuts and bolts, but I wouldn't put it inside an engine. When I rebuild an engine, I may use brake cleaner to clean head bolts and camshaft bearings, but then I use compressed air to dry everything completely and liberal amounts of oil to keep everything happy.

Okay, here's my refined take on Seafoam: The solvents thin your oil, possibly causing premature engine wear, then they gradually evaporate. The oil burns along with the fuel, potentially fouling your plugs and your emissions control system.

Gosh, where can I buy this stuff!
 
#17 ·
If you do add it to your oil, you're supposed to change it after a day or so of mild driving.


Btw.... after using it, my mpg is up to ~19-20 from 14. is it snake oil? is it a coincidence? dont know. I didnt use it in the oil or fuel... just in pcv valve.
 
#20 ·
...
Btw.... after using it, my mpg is up to ~19-20 from 14...
Well hi all, i was reading and trying to understand why is everybody doing this and what are the gains.

I have an 05 with the H6, pretty much like you have absolut, and i always run about 350-375 miles with one tank so that puts me around what 22-23 mpg...

Don't know how you can get 14mpg with your H6... Anyone else?

Before anyone asks, i have 135,000 miles on mine.

Any other advantages to that seafoam thing?
 
#18 ·
Went out and did this to my car today. I only did 2 of the three runs of seafoam, cause the way the engine was behaving was freaking me out a little. That being said, I think I would have been fine to do the third. Thanks for putting all this info together in one place.

For you non-believers who don't think the Seafoam does anything check out the attached picture. These are pictures of the PCV nipple that goes into the intake. I fed the seafoam all the way through the PCV hose and through this nipple so they would get cleaned as well, and as a test just to see what the Seafoam did. Granted, the seafoam was most concentrated going through the hose and nipple, but it still did an impressive job a removing all the junk that was in the hose and nipple.
 

Attachments

#21 ·
Techron - For Clean Combustion Chambers

I've heard of Seafoam, but have never used it. I know it's been around a long time, and was developed for marine applications, if memory serves. I would only use it if there was no better way to improve performance. Regarding the crankcase, I would rather use an engine flush if I suspected an abundance of deposits, not a product that is meant to run your engine on diluted oil, as someone else mentioned.

Aside from the crankcase, I've found a great performance-enhancing product that I've used for years and works very well to clean jets/injectors/combustion chambers/valve seats (there's a dedicated version for fuel injectors). It's Techron. Works like a charm for all 3er's and Civics I've owned. Just pours into an empty gas tank before fill-up and always has produced a noticeable result for me.

I understand the combustion chamber is not the crankcase, and oil is not gasoline, but Techron has always done the trick for me, maintenance-wise.

:2cents:
 
#22 ·
So I'm new to subaru & this forum & wanted to see what this seafoam talk is all about. I just watched the seafoam ad video above & dont want to seem like the new guy jerk but holy crap that was scarrrry. I charge lots of money to tell people they ruined their motor by hitting a rain puddle & ingesting less liquid than they poured in that video.

I am sure the stuff works but so did pouring ATF down carbs 30 years ago & by pouring I mean only slightly faster than OP suggested & makes the exact same smoke cloud & so does misting water down the throttle,on everything inside the combustion chamber anyway just not the backs of the intake valves.

I know the old GM decarbon stuff went in kinda fast but not like that vid & all professional decarboners go through either a atomizer or through a small diam hose. Heres hoping people listen to the original posters application method more than the video.

Nice to have clean valves & pistons, though I am a little curious what the solvent that is also a lubrucator does to O2 & cat. How long has this stuff been around,many years?

BTW add a Qt of that trans fluid I mentioned above to oil & idle 10 min before oil change will also clean sludge & soften seals like the seafoam claims also.
 
#23 ·
If SeaFoam was water, I could agree with you. But the fact that it is volatile solvents makes it a different animal when it comes to hydrolocking an engine. If you were to pour it in fast enough, it's possible. But it's supposed to be introduced in a controlled rate, and I'm sure it evaporates quite fast in the hot manifold. Get's a nice cloud of vapors in there to get to the backs of valves and the tops of pistons.

It's been around for many years. But it's a huge unknown secret, apparently. Once you discover it and try it, it's quite useful in any IC engine including small engines.
 
#26 ·
It is, and sure, it probably saw a much higher concentration of seafoam, but it the fact that it came so clean tells me that the Seafoam is pretty potent stuff. And for me, I got relatively little smoke, and put the seafoam in very slowly with the baby bottle method.
 
#31 ·
When on the farm we used to use water. With the engine running we would slowly pour water into the carb or intake somewhere. The water would boil creat steam and clean out injectors, intake cross-overs etc.
I will be doing this the same way (into the PCV hose) with water to my 2000 Outback next oil change.
I've never documented mileage, hp, etc. before and after, just seat of the pants conclusions. I did know a few farmers that did this type of treatment to their equipment.
 
#34 ·
When on the farm we used to use water. With the engine running we would slowly pour water into the carb or intake somewhere. The water would boil create steam and clean out injectors, intake cross-overs etc.
year old thread, but gotta start sometime...

this is called an italian tune-up. used to pour the water right into the carb.

@rockhopjohn - it's so powerful, it cleaned your fingers too! :29:
 
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