Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Spring is almost here, and we been getting quite a few 60F plus days.  While waiting for the last snow storm/blizzard to arrive before preparing the snowblower for summer and fall hibernation, I thought I get in the spring cleaning mode and get my lawn equipment up and running. 

Besides getting new fuel lines, fuel filter, air filter, and a new spark plug, what is the proper way to service a diaphram carburetor?  What's involved?

Also, I need a new bump feed head.  Any recommendations on the quick and easy loading heads from Stihl, Shindaiwa-Echo brands?

Re: "SeaFoam" and Gas String Trimmer tune-up.
Curious as to what this SeaFoam "miracle product" was all about, I checked into the ingredients by looking up the manufacturers mandatory MSDS (Material Safety Data Sheet) on this product.  I found that it contains:  "Pale Oil" 40-60% (by weight), "Naptha" 25-35%, "IPA" 10-20%.  "Pale Oil" is simply another name for common mineral oil, the same stuff that is found in most engine oils (without the additives).  "Naptha" aka VM&P (Varnish Makers and Painters) naptha, is what is more commonly known as "gasoline" without the additives, aka "white gas".  "IPA" is simply Isopropanol which is more commonly known as Isopropyl Alcohol or "Rubbing Alcohol" (diluted).  All the "degumming" and cleaning effects of this compound can be attributed to the solvent effect of the naphtha and the Isopropanol.  Obviously, since your gas tank has a copious amount of gasoline already in it, adding more is not likely to accomplish anything.  The real solvent effect is in the Isopropanol which in 10-20% concentration, is likely to have little solvent effect upon gum, varnish, and other petroleum oxidation products unless you use it "straight".  Currently, most "oxygenated fuels" contain around 10% Ethanol (another alcohol) which is also an excellent solvent.  So adding more alcohol to fuel that already contains another form of alcohol is not likely to be particularly beneficial.  Also, there are many anecdotal accounts of small engine repairmen blaming the deterioration of internal carburetor rubber diaphrams and other such parts, on the effects of alcohol and other additives in current gasoline formulations. 

The best way that I know of to properly service a diaphragm type small engine carburetor, is to buy a carburetor rebuild kit and rebuild the carburetor.  The necessary tools are minimal and the only other thing required would be instructions (see your local library), and a can of carburetor cleaner from your local wally world or auto parts supplier.   A wrench to remove the carburetor, and a couple of screwdrivers to disassemble the thing is usually all that is required.  The diaphragm in a small engine carburetor acts by using crankcase pressure pulses to pump gas from the tank to the carburetor.   They are thin and really flimsy.  They also do not last forever.  Good luck.

Interesting observation rktc. 

However, I'm wondering if "every" ingredient in Seafoam is listed?   Seafoam is also used as a very good fuel stabilizer.  Which of the ingredients you listed would contribute to that function? 

From your analysis, one would conclude that you don't believe that Seafoam does what it claims to do.  Would I be wrong in making that assumption?   If so, it would appear that myself and many others have been duped into believing that it actually works.  I know I've run Seafoam in a number of small two stroke engines with no particular remarkable observation of improvement.   That might be partly due to my steadfast regular maintenance and the moderate use of Seafoam on a regular basis on machines I'm always using.  

Now, I do have at least two small engines that I hadn't used in many years and they had never been treated with Seafoam.  One engine was a small Tecumseh two cycle  mounted on an ice auger.  It had sat unused for at least ten years.  I recall that it had run pretty lump when I put it away.  Probably why I quit using it.   So, one day when I was giving my OPE the Seafoam treatment, I pulled down the Tecumseh engine, clamped it down on a WorkMate bench and  put in fresh fuel.    After a considerable amount of effort, It fired up and ran lumpy as usual.  I poured about an ounce of Seafoam into the fuel tank and within a minute or so, the engine began to emit very thick blue/white smoke.   Far more than normal for a two cycle.  About two to three minutes later, the smoke had cleared up and the engine was responding to throttle input crisply and idled down very nicely.  I can't make a definitive scientific conclusion that Seafoam is what cured the engine's ailments but I can't think of anything else that would have done so. 

I was so impressed with the results I got with the ice auger engine, I decided to pull out an old 1976 Johnson 15 h.p. outboard engine that I had retired for being down on power and difficult to start.  I had bought it used and don't know it's history.  I do recall that it was down on power in a big way.  I used to put the Johnson on a very light 14' aluminum boat for my young 12 year old nephew to use.  A kid down the lake had a new Yamaha 6 h.p. engine that would run neck and neck with the 15 Johnson.  I recall that I had spent numerous hours cleaning and adjusting the points, putting in new plugs, cleaning the carb probably five times and with virtually no improvement in performance.   After my nephew grew into his teens, he no longer used the 14' with the Johnson so that motor was retired to the garage about 15 years ago.   After the Tecumseh engine revival, I gave the old Johnson the same treatment.  This time, I set the pistons so that I could pour in Seafoam to let is sit in the cylinders over night.   The next day, I mounted the engine on a 45 gallon drum half full of water, put in some fresh fuel and struggled to get it running.  It fired up and ran as it normally did but puking out a thick cloud of blue/white smoke .  It  idled fairly well and would rev up sluggishly.   I added a good dose of Seafoam to the fuel and got more smoke for a few minutes then it cleared up.  I put the motor on the same old aluminum boat, added more fuel and Seafoam to the tank and took it out for a test ride.  The engine ran better than normal and would occasionally, emit  the occasional puff of heavy smoke.   I'm not exaggerating,  after five minutes or so, the performance improvement was remarkable.   It spins up to maximum rpms quickly and actually makes power much closer to a 15 than a six.  Again, I have no scientific proof that Seafoam was the ingredient that brought power back to this engine.  I do know however ,that the engine makes noticeably more power than it ever did before the treatment.   My assumption is that the rings were probably carboned up and the Seafoam may have freed up the rings to improve compression.   

In summary, I do not challenge your analysis of Seafoam ingredients.   If your intent is to dispute the effectiveness of Seafoam, I cannot scientifically prove that you are wrong there either.  On the other hand, from observations of my personal experience with many years using the product, I have no intentions of stopping use of it any time soon.