chain saws

[mud runner]

ok im fixing up a chain saw for my uncle its a McCulloch Timber Bear it looks exactly like this one McCulloch Timber Bear Mint Condition Chainsaw New Chain 20" Bar 610 620 Beaver | eBay but mine doesent look this good but the problem im having with it is i can get it to start for about 5 sec. max and then it dies and it wont start and i think i know what the problem is it wont let gas go through the line to get to the carb iv tried alot of stuff to get it to run right but i cant seem to get it running right any ideas

 

[motoman159]

clean carb, new plug, new gas lines.

 

[mud runner]

alerady done 15151515

 

[Braaaptor]

Its time for a diaphragm (rebuild) kit in that carburetor.

If you haven't already done so, replace the weighted fuel filter inside the tank. It has a felt element inside of it which will pack up with debris over time. You can't clean it; it must be replaced.

You said you already installed new fuel line. Good.

Now about the carburetor...That saw should use a Walbro HD series carbuetor. It works much like the carbs found in some snowmobiles and almost all jetskis, just on a much smaller scale. Those little saw carburetors use fuel pump diaphragms which eventually grow hard and brittle with exposure to gasoline. It is probably time for you to install a kit in that carburetor.

Take the carb off the saw, disassemble it, and go get a rebuild kit. Your carb should take a part number K10-HD kit. You can find one online or at your local small engine shop. After giving the carburetor a good cleaning, check the fuel strainer screen on the fuel pump side of the carburetor, and be SURE it is clean. They are known to become blocked with sawdust.

Also, check the gasket which goes between the carburetor and the intake manifold. It must be in good shape or you'll have an air leak.

Once you get ahold of a kit, reassemble the carburetor with fresh diaphragms and gaskets, set the hi and lo speed adjusters out 2 turns each, and crank it up. The engine should run fairly well with those settings. Once you warm the saw up, adjust the low speed adjuster until the saw idles smoothly and accelerates cleanly. You want the low speed side to be set lean enough that the engine doesn't flood out, but rich enough that it will accelerate cleanly when you get on the throttle.

Once the low-speed circuit has been adjusted, hold the throttle wide-open and turn the high speed screw in until the engine screams and begins to bog out. Then back it off until the engine begins to stumble (burble) slightly. Leave it there. You want a chainsaw to run rich at WOT when the engine is not under a load, because when you put a load on it, the engine will need more fuel.

Any questions, just ask! I fix lawn equipment and saws for a living and have lots of experience.

 

[mud runner]

Its time for a diaphragm (rebuild) kit in that carburetor.

If you haven't already done so, replace the weighted fuel filter inside the tank. It has a felt element inside of it which will pack up with debris over time. You can't clean it; it must be replaced.

You said you already installed new fuel line. Good.

Now about the carburetor...That saw should use a Walbro HD series carbuetor. It works much like the carbs found in some snowmobiles and almost all jetskis, just on a much smaller scale. Those little saw carburetors use fuel pump diaphragms which eventually grow hard and brittle with exposure to gasoline. It is probably time for you to install a kit in that carburetor.

Take the carb off the saw, disassemble it, and go get a rebuild kit. Your carb should take a part number K10-HD kit. You can find one online or at your local small engine shop. After giving the carburetor a good cleaning, check the fuel strainer screen on the fuel pump side of the carburetor, and be SURE it is clean. They are known to become blocked with sawdust.

Also, check the gasket which goes between the carburetor and the intake manifold. It must be in good shape or you'll have an air leak.

Once you get ahold of a kit, reassemble the carburetor with fresh diaphragms and gaskets, set the hi and lo speed adjusters out 2 turns each, and crank it up. The engine should run fairly well with those settings. Once you warm the saw up, adjust the low speed adjuster until the saw idles smoothly and accelerates cleanly. You want the low speed side to be set lean enough that the engine doesn't flood out, but rich enough that it will accelerate cleanly when you get on the throttle.

Once the low-speed circuit has been adjusted, hold the throttle wide-open and turn the high speed screw in until the engine screams and begins to bog out. Then back it off until the engine begins to stumble (burble) slightly. Leave it there. You want a chainsaw to run rich at WOT when the engine is not under a load, because when you put a load on it, the engine will need more fuel.

Any questions, just ask! I fix lawn equipment and saws for a living and have lots of experience.

thanks im thanking about taking the carb off of a weedeter im fixing up for him too the motor locked up on it but i got it to free up but im gonna try to get the chain saw running befor i toutch that weedeter and its called weed eater i think its from tractor supply and any ideas on where i can get parts for that chain saw iv been looking but most of the parts they dont make any more

 

[Braaaptor]

thanks im thanking about taking the carb off of a weedeter im fixing up for him too the motor locked up on it but i got it to free up but im gonna try to get the chain saw running befor i toutch that weedeter and its called weed eater i think its from tractor supply and any ideas on where i can get parts for that chain saw iv been looking but most of the parts they dont make any more

The Weedeater brand of trimmer is the bottom of the barrel, quality-wise. They were built cheap, and are kinda meant to be tossed out once something breaks. Sometimes, you can actually take the piston out of the cylinder, sand the cylinder down, unstick the piston ring from the piston, and put it back together. They will run again, such are the loose tolerances in these engines.

Just FYI, the carb from the weedeater won't fit the McCulloch chainsaw. Totally different design.

Its getting hard to find spare parts for these older Mac saws, no matter where you look. Ebay is your best bet for stuff which is an actual Mac-supplied part of the chainsaw. That being said, you can get carburetor kits directly from Walbro, as that HD carb was used on many different makes/models for several years. Fuel line, fuel filters, spark plugs, air filters, etc are not a problem, as they can be had in the aftermarket.

You can easily find a Carlton or Oregon bar and chain to fit that saw when the original ones wear out.

Another good bet for parts would be to talk to an older shop around town that used to sell McCulloch saws and parts. Chances are that if you find an older place, they may still have a stockpile of parts from back in the day. Its kinda like finding parts for Clinton and Lauson engines....difficult, and it gets harder every year...but not impossible.