... from Craigslist ad*. It's a 3HP Craftsman and the seller said it didn't run.
First I pressure-washed the device, to remove the gunk and grass. Next, I replaced the carb's diaphragm and carb's needle-valve and hosed the dude down with carb cleaner.
The machine will now run, BUT
If other than full choke, the engine dies.
My skills at small engine repair are at zero (or closely adjacent), so any helpful hints would be appreciated.
Thanks
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The owner only wanted ten dollars, so I thought the gamble was worth it.
This is significant. It indicates that the ratio of air to fuel in the mix is too high; this can be caused by too much air, or too little fuel.
One possibility is that there's a major air leak somewhere: at anything less than full choke, there's too much air in the mixture to support combustion.
The very first thing I'd check is the bolts or screws that hold the carburetor to the engine; I'll bet they're loose.
If that's not the case, then there's probably a small bit of gunk lodged in a passage in the carburetor, or in the jet, and the next thing to do is to remove and dismantle the carburetor, and do what you should have done the first time you had it apart: blow everything clean with compressed air.
The bolts are tight - I've removed the carb several times, but I'll bet the gasket between the carb and the engine is kerplunked allowing air infiltration. I have some gasket material from which I'll make a new one and give it a try. On a similar quest, this Tecumseh engine has two adjustable needle valves. I adjusted these both to 1-1/2 turns from fully closed. Is that right.
Thanks for the tip.
At the garage sale, I bought a B&D electric edger for $15 and the owner threw in the gas one for another ten.
Even at reduced power - with the choke fully on - this sucker edges like a sumbitch!
1-1/2 turns is the starting point and should run pretty good there.
First, are you sure both screws are for needle valves? Could one be for the idle? Usually there is only one needle to adjust.
Second, if the carb sits on top of the tank, be sure the screen (filter) at the bottom of the pick-up tube is not blocked. Also check to see that water or debris isn't laying on the bottom of the tank. Cleaning just the carb and not cleaning the entire fuel system isn't doing much good.
I use a stainless steel (SS) wire, plucked from a wire brush (held with a pair of needle nosed pliers) to clean and clear the passages (Venturi ?) in the carb. Look in the throat of the carb for them.
Perhaps even a wire cut from a guitar string might work. A carb cleaner can then be used to blow the passages out.
The carb setting sounds right. "turn" is 360 degrees, in this case.
Sounds like you have air leak from the carb gasket, as you said. Take the carb gasket back out. Give it a thin layer of Permatex IIB non hardening gasket sealer on both sides of the gasket. Then, reassemble. It's OK to wear disposable gloves. Alcohol removes any mess. Auto drygas is good. The stuff doesn't want to come off skin, clothes, etc.
Actually, it has THREE needle valves. One, non-adjustable, inside the carb to govern fuel flow to the diaphragm - this is a no-float model - and two on the outside - which I presume are low-speed and high-speed adjustments.
Nah, tank is above the carb and there is no fuel filter.
I found once, when installing a diaphragm, that it can be installed wrong... upside down it would not function as intended. They do need to be installed in the proper orientation. Seems silly but it is true. I put one in upside down and later had to change it (flipped it over) and it worked fine.
The easy way to check for leaks around the gsaket is to spray a little wd40 or something similar around the gasket edges. If there is a leak the rpm will change.
Many thanks for all the helpful suggestions. As each was implemented, the edger got closer and closer to working.
My last removal and cleaning of the carb was followed by replacing the hose from the gas tank to the carburetor. Inspection of the 3" hose revealed itty-bitty bits of it were flaking off, no doubt entering the carburetor and jamming up something.
Edger now runs like a scalded cat. I would have no problem using it as a six-inch Ditch Witch!
Once again, thanks to all for the enlightened advice.
Good for you and glad you got the contraption running. I was wondering about it and your earlier post.
Just today (Wednesday) I finally decided to start my 5 HP power washer. It sat through winter and all summer, so I knew it might be difficult to start. I helped a neighbor a couple months ago start his PW. I advised him to buy some starting fluid. I removed his air filter, shot some in the carb, choked it and had him pull the cord. It took just a few minutes to get him going strong.
Mine sat so long I borrowed his can of starting fluid, hoping that would get me going. I could get the 30 year old engine to fire with the fluid, but it would only run for seconds..
Finally I removed the float bowl, sprayed it down -- all looked well for the moment. The bowl, float and all looked and operated well as I sprayed them down.
What I found: The bolt for the float bowl has passages. My summation was the bolt siphoned fuel from each side and up (from the bowl bottom) through the center of the bolt. The center vertical passage was clogged with some goo. Using a SS wire, plucked from a wire brush I cleared the center (vertical) passage. Put the bowl and bolt back on.
With ether, if you spray it into the spark plug hole. The cylinder wall dries out, and turns a $500 generator into a $75 Ebay item. A "helpful" neighbor did this to my Dad.
Spray ether onto the air filter instead.
Oven cleaner like "Easy Off" is excellent for cleaning carbs. Put all the parts into something like a spaghetti strainer, in the sink. Spray. Wait about a minute, and rinse with water. Sloughs off grease, and varnish very nicely. Dry with a paper towel or two, and reassemble.
The starting fluid product I borrowed from my neighbor has a "lubricant" in it and can be used in the engine cylinders, so the can states.
Valvoline® Extra Strength Starting Fluid
Provides faster, smoother starting
For faster, smoother starting of gasoline and diesel engines in any weather * Starts engines quickly and reduces drain on batteries * Compatible with gasoline or diesel engines * Contains upper cylinder lubricant * For year-round use in cars, trucks, lawn mowers, chain saws, marine engines and motorcycles * Download Product Info PDF * MSDS
Spraying a carb with cleaner ( even as you did) is mostly useless. A carb has to be COMPLETELY dis-assembled and all passages must be free of debris.
I have a guitar string ( High E, smallest one) in my tool box for such things. They are long and sturdy. They fit the smallest of jets. If you know someone who plays guitar, get one from them when they break one or replace their strings, which they do both often.
Good suggestion. Regrettably, I don't know anyone who plays a guitar, even when I slept on top of Janis Joplin back at the University of Texas, she played an autoharp.
Maybe a hippie store will sell a guitar string to a straight dude?
I used a "starting fluid" , and not a "cleaning fluid". One or two shots of "starting fluid" and she fired a bit. Then I cleared the bowl bolt jet with a SS wire. No need for a complete disassemble.
Just don't break it off (or any small wire) in a passage / venturi.
Between a google poster and a top poster the thread got munged.
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