Yes, it is possible, but in succeeding you will have become an expert on the carburetion systems of your appliances and the techniques for recalibrating them. A fully optimized E85 conversion would also have increased compression ratio and/or more advanced spark timing, but that would be icing on the cake in this case.
Startability may suffer. A shot of ether should take care of that though.
On a chainsaw, the fuel tank is integral, so you don't have the option of changing it to an alcohol resistant material. Some tanks are mag, to save weight and I would be worried about rapid corrosion with alcohol. Also, you need to look at the boot/seal between the carb and the crankcase--another specialty item you may not be able to find in an alcohol resistant material.
CSLufkin: May I ask what the purpose of this conversion is?
If it is just for fun, I vote to give it a shot. Like others have said, you will need increased fuel flow, a greater advance on your spark timing, and to ensure that anything that comes in contact with fuel is compatible with E85.
The fuel flow increase can be had by modifying the carburetor, and the spark advance can likely be done by making some sort of a bracket to mount the magneto at location with a lower crank angle compared to the current magneto mounting position.
The extra fuel flow requirement might require enlarging everything from the internal idle passages to the needle and seat to the fuel lines to the breather vent.
Regards
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Thanks Guys, I was out for a few days and missed all your replies until this morning.
I am in Upstate NY (you don't have to be from Alabama to be a Redneck you know)
This conversion would be strictly for fun, and conversation sake.
What percentage more fuel (roughly) will I need to provde?
E85's dirty little secret.. when used as directed will shorten the life of an engine. Remember to flush the engine with gasoline after use and change the mowers oil often.
The fuel system materials have to be compatible and the venting has to minimize moisture absorption. Once that is worked out then the carb needs to be rejetted and youre off to the races.
Good Luck
I believe there is a product, about to hit the shelves, that is a premix/non alcohol blend designed 1st for convenience, 2nd to prevent your tools from crapping out after winter storage. How many of us really take the time to flush out our $75.00 weedwhackers in the fall? It's only gonna get worse with the increase in alcohol percentage in our gas. I would buy the stuff, I think for the convenience factor alone.
To flush the E85 from the fuel system, you want to use gasoline with NO ETHANOL in it. If you are unsure of your fuel sources, you can by an inexpensive test kit that will detect ethanol in the gas.
The folks with classic cars are having trouble with E85. Quite an increase in classic cars lost to fire in the corn belt per my ins agent and some guys are seeing accelerated tank corrosion and seam solder erosion.
Who in his right mind would put E85 in a classic car? They weren't even designed for gasohol (E10)! I would not put E85 in anything not explicitly designed for flex fuels unless I didn't care what happened to it.
He converted to E85 and is lovin it.
There is a local guy that has done the same and likes it's performance in his drag car for the last year and a half. As always, it is not as good or as bad as people say. I would convert my 67 Firebird if the fuel was readily available here. Have seen plenty of 1000+hp turbo and blower cars run on it and they admit to a couple problems but can tell you how to make it right. As far as "classic cars" are concerned, that would require a definition. Can you estimate how many factory original 60's cars are out there verses how many have at least had the carb switched to a Holley, Edelbrock, Demon, etc. Mine has a Quickfuel billet Holley style 4500 series and they offer E85 metering blocks for those that want to build an engine with E85 as the fuel of choice.
I've been running a Craftsman mower with a 10 HP Tecumseh on E85 for about 5 or 6 weeks with no problems. My carb had enough room for adjustment that all I had to do was richen it up with the load screw (not sure on the number of turns out, just turned it till it ran right). I can't quite get enough idle fuel. It'll idle but the gov. makes it surge a little from needing more fuel. I didn't advance my timing and I didn't notice any loss of power. It would probably have more power than gasoline if I did advance the timing. It's also noticably louder, which would probably change if I advanced the timing. I also have a 3.5 HP MTD push mower that I just made run on E85 the last time I mowed. It didn't have an adjustable main jet, so I went the old moonshiners route...choked it till it ran right, then made a stop for the choke at that point so it would stay partially closed all the time (I can still fully choke it for starting). It has an idle adjustment and I had to give it a little more idle fuel than with gas. It runs exactly like it did on gas, with noticably more power. I didn't think the choke method would provide the right amount of fuel at various RPM's, but it seems to run right at any RPM. If I have any problems I'll post here again, but so far everything seems fine!
Something I forgot to mention...When I buy E85 I noticed from one fill to the next the % of gasoline may be a shade different. When I bought my second can I had to richen up the load jet like a 1/4 turn for it to run the same. The pump says the E85 will be a minimum of 70% ethanol, so having this mixture change makes running it in a carb engine somewhat annoying. If this continues to work I may buy a barrel so I can keep it sealed up tight and be able to keep the same carb settings all summer long.
