2 cycle weed wacker engine

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Stelcom66

Minister of Fire
Nov 6, 2014
739
Connecticut
My son gave me an old Sears 17" 25cc weed wacker that his father in law gave him. When I inspected the fuel lines they fell right apart. Got new fuel lines and installed them today, not a sign of starting. I know it's a loaded question with many reasons - but the fuel filter had this cap like thing on it with a very thin tube. Maybe the thin tube went into the smaller diameter line which goes to the carburetor? The filter, fuel line and cap were all loose inside the tank. The cap wouldn't stay on the filter, so I heated the line a bit and put it directly on the fuel filter.

Done fooling with it this evening - I wonder tomorrow should I try removing the fuel filter to see if it starts? When I prime it I don't see any fuel moving in the fuel lines. I assume I should see fuel being directed back into the fuel container via the return line. Besides the bad fuel lines I don't know what else may have been wrong with it.
 
The diaphragms in the carb are almost certainly fried. A new carb may be cheap. That and some new fuel lines may get it going.
 
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Got it to start and run for about a minute after cleaning the carb and transferring the spark plug from my other weed wacker, bought the plug last year. Now I see see fuel flowing in the lines when pressing the primer bulb. Will fool with it again another time.

Part of the trouble was the procedure for starting it that I found online was different than what was on the unit itself.

Looking at reviews - looks like you need to spend at least $200 for good one. Many one start out of five ratings. I don't want to buy one and have the same trouble with fuel lines a few years later. Don't know if there's any way to prevent them from becoming brittle. I had a decent (for an electric) battery weed wacker (or is it whacker?) - but now all the local stores I checked don't carry that 18v battery any more. Even
Black & Decker's new units are 20v. Did find a battery at a battery specialty store, but $59.99! Not going to do that.
 
I have had a Stihl 4Mix for 10 or 11 years now. I use only their oil, even though it's costly. Everything except the string and fuel filter is original - plug, fuel lines, etc. I use it fairly often, so it has a lot of hours on it.
 
if I knew I could get 10 or so years out of one without replacing fuel lines I'd be glad to pay the price. I've heard very good things about that brand whether they're weed whackers, chainsaws, leaf blowers, etc.
 
I also have a Stihl backpack blower, a 2 stroke, for the same time period. Everything on that is original. It doesn't get the use that my trimmer gets, but it's the same age. They both are good starters, due to the primers. The trimmer started first pull after sitting all winter. The blower took 3 or 4 pulls. I haven't touched either carb except to inspect the air filters.
 
My neighbor may have the same blower as you have - he says it's great. Going to ask him if his trimmer is also a Stihl also.

I think the carburetor is shot on mine, wouldn't start when I tried it later today and again no sign of any fuel in the primer bulb or lines.
 
I've had all sorts of weedeaters. Some were ok for small urban settings, but when we moved out to the country they were not up to the job. Parts broke regularly on a Ryobi and the Sears before that was balkier than a stubborn ass. Now I have a Stihl FS85 weedwhacker. It's about 10 yrs old and gets a serious workout several times a year. It's been super reliable and tough. And it runs MUCH smoother. I can now weedeat for hours without my hands going numb. I don't baby this thing at all and it just keeps going.
 
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I did confirm my neighbor also has a Stihl grass trimmer (proper term on their website). Bought it from a local Agway store. Their website doesn't even show grass trimmers but I've learned you can't always go by that. The option may be though to buy online and pick up at that local store, which would be fine with me.
 
With not working full time a new grass trimmer isn't in the budget right now. I've been using a Black & Decker trimmer for several years. I'm down to one good battery. Searched online and the stores don't carry them, except for one battery specialty store, but for $59.99! Forget that. I'm not one to buy online - but I ended up ordering a 2-pack from Amazon for about $39 + tax. I chose free shipping which would have meant delivery Monday, but they arrived yesterday. Not bad for free shipping since I ordered them two days before. I see why so many like Amazon.

The batteries may weigh slightly less than the originals - maybe slightly less output, but if this will get me by for a few more years I'm fine with that. So many consumer grade trimmers are battery powered these days. At least that's what the big box stores seem to be featuring,
but they're typically 40+ volts. Black & Decker's base model went from 18v (mine) to 20v. At least with a gas trimmer it's not likely that there will be obsolete components after 5 or so years.
 
With not working full time a new grass trimmer isn't in the budget right now. I've been using a Black & Decker trimmer for several years. I'm down to one good battery. Searched online and the stores don't carry them, except for one battery specialty store, but for $59.99! Forget that. I'm not one to buy online - but I ended up ordering a 2-pack from Amazon for about $39 + tax. I chose free shipping which would have meant delivery Monday, but they arrived yesterday. Not bad for free shipping since I ordered them two days before. I see why so many like Amazon.

The batteries may weigh slightly less than the originals - maybe slightly less output, but if this will get me by for a few more years I'm fine with that. So many consumer grade trimmers are battery powered these days. At least that's what the big box stores seem to be featuring,
but they're typically 40+ volts. Black & Decker's base model went from 18v (mine) to 20v. At least with a gas trimmer it's not likely that there will be obsolete components after 5 or so years.

Might be worth looking around for an adapter. I know DeWalt makes one for the older 18v tools to run 20v batteries, the only issue is you can't leave them connected to the adapter after use it the circuity drains the battery overnight.
 
That was my other concern - what if the charger no longer works. Will keep an adapter in mind. I should be all set for now, but the new battery isn't as powerful as the original. It'll get the job done. I just hope they won't start to become useless after a few charges.