I have a WeedEater gas-powered trimmer. It has a plastic bulb that you squeeze in order to prime the engine. One of the problems with this system is that the bulb tends to crack and fail after exposure to gasoline containing ethanol. That's just another unfortunate result of the move to ethanol.
This story begins when I take a trip to the store to get a new bulb. I get there and find that they cost up to $8 -- for a little piece of plastic!
Alas, in the process of taking off the small plastic retaining ring that attaches the ($8) bulb to the carburetor, I managed to break it. I tried using J-B Weld, Gorilla Glue, and duct tape, but nothing I tried would fix it, so I had to begin the search for a replacement retaining ring. A quick look through the bone yard at the yard equipment repair shop didn't produce anything I could possibly use as a substitute for the retaining ring.
So I looked further for the part itself and found that no such single part is available for this model -- you have to buy a whole new carburetor. Individual parts are not sold separately. Luckily, I found a carburetor for $24, and I was able to put it on myself, saving the $20 minimum that the repair shop charges.
Chalk up another one for ethanol-based fuel. Add to that problem the inability of the WeedEater folks to use the right material in the primer bulb that would be resistant to the corrosion from ethanol. So I had to go through all that trouble to buy what was probably a 25-cent part.
This entry was submitted by A.K. Rosenhan, PE, and edited by Rob Spiegel.
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Straight gas is definitely better than the ethanol blend for hand held power equipment. There is another option available. STIHL offers Motomix pre blended fuel that utilizes ethanol free high octane gas pre-mixed at 50:1 ratio for use in hand held power equipment. It runs great in their product.
Yes Rob, it eats most anything made from rubber. By the looks of it, the rubber becomes brittle, then just falls apart. Now for "negative consumer reaction to legislation". Who will Congress pay more attention to; a) a guy on a remote island with a few hundred dollars in damaged tools or b) a lobby guy who plunks a million dollars on his desk for reelection?
Same with sugar, Americans pay way more than the international price, but most folks think they don't use enough sugar to whine about the few cents more they pay. To us, its a few cents, to big sugar, its millions. Lobbists pay Congressmen to support bills like the ethanol scam. Demand for corn increases, prices of food increase, the ethanol business is subsidized by tax dollars, the Federal Reserve prints ever more money driving prices even higher and the resultant comments are: It's those damn Arabs!
I don't know about you, but certaily I don't count much to my Congressman. I send them a letter, I get a form letter back that has nothing to do with my topic (other than he is working/fighting hard for me), and we end up paying for the postage (franking). What a system. The best government money can buy.
I'd like to turn the political clock back 200 years.
This story is a good example of environmental stress cracking, which I covered in an article earlier this year. Evaluating the resistance of rubber and plastic materials to new biofuels helps keep materials engineers like me busy. Besides ever-increasing ethanol percentages (your product had better be able to tolerate gasoline containing 25% ethanol if you want to sell it in Brazil!), there are also newer alternative fuels and fuel additives such as biobutanol that need to be considered.
As Beth points out, it's important to keep up on these trends, and make sure that the materials in your product will be compatible.
I am in Royal Oak, two blocks south of the Red Run golf course.
I investigated the engineering program at Oakland University in 1969, and based on what I saw, I enrolled in the Lawrence Technical Institute instead. I graduated with a BSEE and have been in engineering ever since.
And, based on the several jobs and employers that I have had over the years, I suspect that the engineering salary surveys that I have seen are a bit exagerated. Or at least, they don't include this part of the country. How reliable is that data, and have you ever seen the tax returns to verify it's veracity?
Hey, I had a lawnmower that kept wearing out carburator parts. I wonder if it was the ethanol? I just blamed the design and rebuilt the carb every couple years.
Yes, I would imagine it would be hard to find gas stations that sell non-ethanol gas. Even with the directory mentioned in earlier comments, I would guess those stations come and go. By the way, William, where are you in southeastern Michigan. I grew up near Oakland University.
We don't see consumer backlash because the link between the damage and the cause of the damage is not that obvious. Around this part of southeastern Michigan it is hard to find gas that does not have ethanol added. They add ethanol because then water will disolve in the fuel and water is much cheaper. So the profit increases. The downside is that the mix is a bit corrosive, so not only is there an ethanol damage problem, but also a larger corrosion problem. The mix conducts electricity, while pure gasoline does not conduct.
It is amazing how many ways our modern materials can be damaged- sun, chemicals, ethanol gasoline, and so on. Short sighted engineers can cause problems in the field where a little common sense and consulting could resolve them before they happen.
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