Sea Foam Diesel Treatment Recommendations

OK, I bought a gallon of Sea Foam after hearing so many rave reviews.

I watched the manufacturer's video on treating diesel engines. But their example was a pickup truck. I'm wondering how other boaters with diesels do it.

1) The video says to start with 2 ounces per gallon into the fuel tank. My tanks hold 100 gallons each, and I have two engines. I'd rather not buy 400 ounces. Even if I do it when they're half full, that's 200 ounces. I only have the one gallon.

2) The video next shows adding it to the truck's fuel filter. I have one Racor and two filters on each engine. Can I just refill the Racor with Sea Foam, and leave the filters alone?

Any other tips/suggestions?

Thanks!!

Why do you think it is necessary?


Small dosages may not hurt anything, and may actually do nothing, but then why are you spending the money?


If it breaks loose large chunks of carbon, I have heard that's not great for the engine either.


Seems like everyoneone is looking for a miracle in a bottle....


Remember for every success story you read, how many bottles were sold and a huge percentage either had issues or nothing at all.

Personally I would not use it at all unless you have real signs of trouble now.

If you go for it then simply add it to the tank. Add what you have and see if it makes any difference.

I don't agree with filling filters as that can give a big load of questionable "fuel" to the engine. Diluted in the tanks will not shock the system.



A lot of these "recommendations " are marketing nonesense and may not really be good for your boat. Testimonials are great but also need to be taken with care.

TO be clear I have used SeaFoam and still do in my small gas engines, O/B and old Yamaha generator. It will help to keep the carburettors clean. It won't clean them if actually plugged but if not totally plugged it seems to dissolve the start of varnish improving running..

On your diesel the injection system depends upon the fuel lubricity to lube the moveing parts, injection pump and the injectors. The Seafoam will reduce that lubricity which could lead to damage. The gassers don't have those moving, high load parts.

The following can be used as a guide that not all additives are worthwhile although it does not include Seafoam.


Lubricity Additive Study Results - Diesel Place : Chevrolet and GMC Diesel Truck Forums

What problem are you trying to solve? What does the manufacturer recommend?

IMHO, snake oil. Poppycock, twaddle and horsefeathers.

Remember STP?

Xsbank said:

What problem are you trying to solve? What does the manufacturer recommend?

IMHO, snake oil. Poppycock, twaddle and horsefeathers.

Remember STP?

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Snake oil perhaps, but I had an annoying, noisy sticking tappet in my 5l v8, so I tried STP when an oil change didn't work. STP did the job.

I was afraid someone was going to ask...

No real problem. Just a pair of 1982 vintage Perkins' which tend to smoke a bit on start up, haven't had injectors taken out and cleaned in who-knows-how-long, have turbos, and don't get run up to full RPMs as often or for as long as they should.

Talk around the docks is that Sea Foam is a good preventive measure for all these things. So many different people suggested I really, really should buy some that when I found a local place that sold it in gallons, I grabbed one.

You guys are giving me second thoughts. Still, tossing a half-gallon in each 100-gallon tank probably won't be a bad thing. Maybe I'll just do that and be done with it.

Talk around the docks? And who of those is really an expert on the subject?


I know dock talk isn't always a bad thing...as for some topics, experts are few and rarely handy......but my experience is often dock talk is useless in a vacuum, and sometimes outright dangerous.


At some point, research is necessary.

Sometimes the MSDS will give you clues about ingredients. I suspect SeaFoam is very similar to diesel fuel, except in price.


Years ago I bought Diesel Kleen on recommendations. I think it was mostly a "feel good product".


I'm pretty sure the engineering standards organizations would publish specifications for such products if it was possible.

CaptTom said:

I was afraid someone was going to ask...

No real problem. Just a pair of 1982 vintage Perkins' which tend to smoke a bit on start up, haven't had injectors taken out and cleaned in who-knows-how-long, have turbos, and don't get run up to full RPMs as often or for as long as they should.

Talk around the docks is that Sea Foam is a good preventive measure for all these things. So many different people suggested I really, really should buy some that when I found a local place that sold it in gallons, I grabbed one.

You guys are giving me second thoughts. Still, tossing a half-gallon in each 100-gallon tank probably won't be a bad thing. Maybe I'll just do that and be done with it.

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If your Perkins isn’t smoking when cold it’s not running. It will remain “cold” and smokey until it’s been run under load for a few minutes. It’s not a modern (clean) diesel. Return the Sea Foam and buy a case of beer (or 2)

I used SF in old engines that others threw away ... wouldn’t turn over.

Put some SF down the carbs w the carbs up and spark plugs down. After 1-3 days rotate the engine 180 degrees and pour a bit in each cylinder hole after removing spark plugs. Hold the engine however and use a long wrench .. tap w hammer while holding pressure on wrench. Very few old outboards won’t free up this way.

But to free up or clean up rings and ring grooves one would need to get the SF into the combustion chamber in sufficiently low quantities not to cause problems from too much pressure. And enough to wet the cyl walls w SF so it seeps down the cyl walls and into the rings.

I could do that through the glow plug holes.
But diesel engines don’t have domed pistons and the SF would probably puddle in the depressions on the piston crowns.

Ski or others would/will probably either dismiss this as not a good idea and I have never done it but there is someone on TF that has essentially done this on a car. The problem is getting the SF into the rings to soak them free of carbon and varnish. If I was to do this I’d be extremely careful not to put too much SF in the combustion chambers possibly causing big troubles.

But there’s a possibility of causing the rings to move properly in the grooves to increase compression. May increase performance and reduce smoking.

Seafoam is something I put in my tired land diesels to make them smoke less. It’s suppose to slow down the rate of combustion. Some engines it worked on and some it didn’t. Some engines cleaned up with more frequent oil changes and some did not. If an engine just marginally failed an opacity test, a quart in 30 gallons sometimes made the difference. Wish I could give you more scientific answers but I can’t.

I wouldn't wory about something like a Perkins 4.101, 4.108, or 70s or early 80s (not .4) 6.354 smoking at start up until cruise. They all seem to do it, turbos more than others. Midlife ones more than newly rebuilt one's, but none don't do it.

If sea foam in fuel, or the occasionally fill of a fuel filter would hurt things -- we'd know it by now. It isn't a new elixer. I suspect.

It is unlikely that putting it in the fuel filter will work magic. Ive just never seen that myself of heard it 1st hand. But, maybe long term it helps. There's a lot of people who say it does -- but same is true of placebo.

My last boat was smoky, an 6.354MGT turbo and hadnt been run for years when I bought it. It may have helped it over time, I'd like to think it did -- but running it might also have done the trick!

I occasionally fill a fuel filter with it when changing. Why? It is just a convenient way to avoid needing to bleed or bleed as much. I pour a little from the bottle into one filter, and a little into the other, and the two drops left into the tank. I find it easier than getting a small amount of clean diesel.

Maybe it helps, maybe not. But, personally, I'm not worried about it hurting anything in the two seconds before it goes through the return.

The fuel filters on many of these are a pain to pre-fill, although there is a screw on upgrade available.

When I do it, I use a thick piece of masking tape to hold the bottom on as tight as I can until I get it bolted back in, then pull off tape.. It still weeps a little, but I can often avoid bleeding or, at the least, nees to bleed much less.

WE use Sea Foam as a problem solver. Stuck old outboard , fine.

Small electric fuel pump stuck? fill it and wait a day or two ,usually problem solved.

AS a constant treatment Bio Bore , or a bug killer of some variety helps most boxes for fuel..

I will admit that Sea Foam has helped in keeping the carburetor jets clean in my Case and Gravely land equipment. I am not a big proponent of “snake oil” but for specific issues the right chemical is useful.

For outboard motors

I use it in my Tohatsu 20hp which hangs off my stern all year. I also run my engine dry after using it and use only premium gasoline with no ethnol.

yep,,,bought a can of it and poured it into a mason jar....dropped my little honda outboard carb in the jar for a week, wow, it turned white which was all ethanal coming out of all the jets.

I've cured multiple injector, carburetor, and also transmission valve body ills over the years with Seafoam. It's a very valuable tool for maintenance. Running some through is a great idea. You have two problems:

a) treating the system effectively if you have large tanks

b) Seafoam is very volatile, so you will loose a lot of the efficacy if you treat a large tank and let it sit for a long time w/o running the fuel.

I would say you need to play with a low tank(s). Get them low, add it, then run them as low as practical/safely that you can.

PEA (polyetheramine) is also an outstanding product for this purpose and less volatile, but I think would be too expensive as it is more expensive (it is the main active ingredient in Techron and Gumout Regane).

do you think Sea Foam can help my Tohatsu 3.5 hp 2 stroke outboard? I had the carb rebuilt in September 2018, ran fine about 2 hrs total . then I drained the tank and ran till it stopped, then drained the fuel bowl in the carb and put away in the basement till July this year.
started up fine but ran 5 minutes then quit. ran with choke out a few minutes then died.
put seafoam in the tank or soak the carb in seafoam mason jar?
what is Sea Foam anyway? kerosene? acetone?

adornato said:

a) do you think Sea Foam can help my Tohatsu 3.5 hp 2 stroke outboard?


b) what is Sea Foam anyway? kerosene? acetone?

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a) My instinct is to say no. Seafoam will lift varnishes and deposits that can clog carb jets, injectors, solenoids, etc. If you stored it properly as you said and it was rebuilt as you said, it's not happening from that.

(Caveat with the rest - I'm no two-stroke expert). I think that sounds like there's an air leak. Do you prime it? If so you create enough pressure to draw fuel, then it bleeds down. I'd first start looking along those lines - a hose that got damaged moving it around or the tank(s). Just a first guess.

Other thing to try is go to a fishing forum where people who really know and work on these things may know more probable causes (maybe someone here will know).

b) It is proprietary but it's a blend of petroleum distillates and aromatic hydrocarbons. I looked into trying to find out what was in it and if I could "homebrew" some a few years ago. I wanted to have a large amount of it for a cylinder head/piston cleaning project. Decent search revealed no real answers.

I found one guy who said he figured it out and said it was something like 70% white gas (stove fuel), 20% acetone, 5%MEK and 5% isopropyl alcohol (or something like that; this was a few years ago). I had all that stuff on hand so I mixed a pint and it was no where near as effective, and the components wouldn't even stay in suspension (polar and non-polar ingredients as you can see).

My side exhausting 315 HP Yanmar was sooting up the side of the boat until I poured the specified amount of Power Source Diesel Klean into my tanks. Before that, my fingertips came away blackened from the red hull aft of the exhaust after an hour or two of running. Nowadays they come away CLEAN with no evidence of dirt after hours and hours.

I noticed at NAPA yesterday a new to me “marine” SeaFoam.

And yet, there are those who claim that all additives are snake oil. I will not run any diesel without an additive to raise the lubricity of today's ULSD fuel. The irony of those "snake oil" folks is that refiners use, wait for it, yes, an additive to raise the lubricity of ULSD fuel to a minimum standard. Unfortunately, that minimum is not sufficient for many components especially those in common rail engines. Anyone owning an engine that uses a Bosch CP4 injection pump and is not using a lubricity improver, well, get ready, cuz your pump will eventally fail. There are numerous examples of these pumps actally exploding. Whether they do or not, the internal wear spreads metal shavings throughout the system. On pickup trucks, the repair costs around $13K. All fuel lines, the fuel cooler, all injectors have to be replaced. Even the fuel tank has to be removed and flushed clean. My point is, additives are not snake oil. Owners of a Lehman or Perkins probably have nothing to worry about, probably.

rgano said:

My side exhausting 315 HP Yanmar was sooting up the side of the boat until I poured the specified amount of Power Source Diesel Klean into my tanks. Before that, my fingertips came away blackened from the red hull aft of the exhaust after an hour or two of running. Nowadays they come away CLEAN with no evidence of dirt after hours and hours.

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rgano said:

My side exhausting 315 HP Yanmar was sooting up the side of the boat until I poured the specified amount of Power Source Diesel Klean into my tanks. Before that, my fingertips came away blackened from the red hull aft of the exhaust after an hour or two of running. Nowadays they come away CLEAN with no evidence of dirt after hours and hours.

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I had exactly the same situation with my twin 4LH-STE Yanmars years ago. The Diesel Klean cleared up the heavy soot, and the engines run smoother. Also, my engines call for a minimum cetane of 44, the world standard except for the US, which is 40.

bykpjfk said:

I had exactly the same situation with my twin 4LH-STE Yanmars years ago. The Diesel Klean cleared up the heavy soot, and the engines run smoother. Also, my engines call for a minimum cetane of 44, the world standard except for the US, which is 40.

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Yep. That snake oil worked. Not a surprise to me but I wonder whether the snake oil guys will acknowledge that some snake oils do work.

Or buy engines that don't require snake oil..


Sorta kidding....I go with the Caterpillar philosophy. If you need it, use it, if you don't, don't.

Running a low dose of SeaFoam on newer marine engines will keep them clean.

However, running a high concentration of SeaFoam in older engines can loosen carbon deposits, if any. Carbon deposits are very hard and have sharp edges which can harm engine internals.

On automobile turbo engines, the carbon deposits loosened by high doses of SeaFoam have broken turbo vanes on the exhaust side.

On Lehmans, Bob Smith or Norm Dribble recommended Marvel Mystery Oil as the only thing to add to the fuel.

CatalinaJack said:

I will not run any diesel without an additive to raise the lubricity of today's ULSD fuel. The irony of those "snake oil" folks is that refiners use, wait for it, yes, an additive to raise the lubricity of ULSD fuel to a minimum standard. Unfortunately, that minimum is not sufficient for many components especially those in common rail engines. Anyone owning an engine that uses a Bosch CP4 injection pump and is not using a lubricity improver, well, get ready, cuz your pump will eventally fail.

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And this is the thing.

The inherent lubricity in diesel has changed over time.

Would you run a modern Mercedes on 1950s full-leaded gasoline? Or a 1940 Ford coupe on modern 93 unleaded with 10% ethanol?

People argue the additive question like engines and fuel are constant over time. They are not.

Pulled from the web , about 9 years ago.
Notice how many "old friends" areactually harmfull!



In Order Of Performance:

1) 2% REG SoyPower biodiesel HFRR 221, 415 micron improvement. 50:1 ratio of baseline fuel to 100% biodiesel 66.56 oz. of 100% biodiesel per 26 gallons of diesel fuel Price: market value

2)Opti-Lube XPD Multi-purpose + anti-gel cetane improver, demulsifierHFRR 317, 319 micron improvement. 256:1 ratio 13 oz/tank $4.35/tank

3)FPPF RV, Bus, SUV Diesel/Gas fuel treatment Gas and Diesel cetane improver, emulsifier HFRR 439, 197 micron improvement 640:1 ratio 5.2 oz/tank $2.60/tank
4)Opti-Lube Summer Blend Multi-purpose demulsifier HFRR 447, 189 micron improvement 3000:1 ratio 1.11 oz/tank $0.68/tank

5)Opti-Lube Winter Blend Muti-purpose + anti-gel cetane improver HFRR 461, 175 micron improvement 512:1 ratio 6.5 oz/tank $3.65/tank 6)Schaeffer Diesel Treat 2000 Multi-purpose + anti-gel cetane improver, emulsifier, bio-diesel compatible HFRR 470, 166 micron improvement 1000:1 ratio 3.32 oz/tank $1.87/tank
7)Super Tech Outboard 2-cycle TC-W3 engine oil Unconventional (Not ULSD compliant, may damage 2007 or newer systems) HFRR 474, 162 micron improvement 200:1 ratio 16.64 oz/tank $1.09/tank
8)Stanadyne Lubricity Formula Lubricity Only demulsifier, 5% bio-diesel compatible, alcohol free HFRR 479, 157 micron improvement 1000:1 ratio 3.32 oz/tank $1.00/tank
9)Amsoil Diesel Concentrate Multi-purpose demulsifier, bio-diesel compatible, alcohol free HFRR 488, 148 micron improvement 640:1 ratio 5.2 oz/tank $2.16/tank

10)Power Service Diesel Kleen + Cetane Boost Multi-purpose Cetane improver, bio-diesel compatible, alcohol free HFRR 575, 61 micron improvement 400:1 ratio 8.32 oz/tank $1.58/tank
11)Howes Meaner Power Kleaner Multi-purpose Alcohol free HFRR 586, 50 micron improvement 1000:1 ratio 3.32 oz/tank$1.36/tank

12)Stanadyne Performance Formula Multi-purpose + anti-gel cetane improver, demulsifier, 5% bio-diesel compatible, alcohol free HFRR 603, 33 micron improvement 480:1 ratio 6.9 oz/tank $4.35/tank
13)Used Motor Oil, Shell Rotella T 15w40, 5,000 miles used. Unconventional (Not ULSD compliant, may damage systems) HFRR 634, 2 micron improvement 200:1 ratio 16.64 oz/tank price: market value 14)Lucas Upper Cylinder Lubricant Gas or diesel HFRR 641, 5 microns worse than baseline (statistically insignificant change) 427:1 ratio 7.8 oz/tank $2.65/tank
15)B1000 Diesel Fuel Conditioner by Milligan Biotech Multi-purpose, canola oil based additive HFRR 644, 8 microns worse than baseline (statistically insignificant change) 1000:1 ratio 3.32 oz/tank$2.67/tank

16)FPPF Lubricity Plus Fuel Power Multi-purpose + anti-gel Emulsifier, alcohol free HFRR 675, 39 microns worse than baseline fuel 1000:1 ratio 3.32 oz/tank $1.12/tank

17)Marvel Mystery Oil Gas, oil and Diesel fuel additive (NOT ULSD compliant, may damage 2007 and newer systems) HFRR 678, 42 microns worse than baseline fuel. 320:1 ratio 10.4 oz/tank $3.22/tank

18)ValvTect Diesel Guard Heavy Duty/Marine Diesel Fuel Additive Multi-purpose Cetane improver, emulsifier, alcohol free HFRR 696, 60 microns worse than baseline fuel 1000:1 ratio 3.32 oz/tank $2.38/tank 19)Primrose Power Blend 2003 Multi-purpose Cetane boost, bio-diesel compatible, emulsifier HFRR 711, 75 microns worse than baseline 1066:1 ratio 3.12 oz/tank $1.39/tank



CONCLUSIONS: Products 1 through 4 were able to improve the unadditized fuel to an HFRR score of 460 or better. This meets the most strict requirements requested by the Engine Manufacturers Association. Products 1 through 9 were able to improve the unadditized fuel to an HFRR score of 520 or better, meeting the U.S. diesel fuel requirements for maximum wear scar in a commercially available diesel fuel


For further study.
Fuel Property Testing: Lubricity - DieselNet


https://www.dieselnet.com/tech/fuel_diesel_lubricity.php
The most important bench tests are the High Frequency Reciprocating Rig (HFRR) and the Scuffing Load Ball-on-Cylinder Lubricity Evaluator (SLBOCLE).

Supposedly even that "now older" diesel supplement test was potentially in error as I believe the "scuffing" measurement part was not done properly or scientifically....


So again....beware of what you read...even supposedly widely accepted research.