Homelite chainsaw won't run steadily

[Wood Duck]

I have a crappy homelite chainsaw that has never run consistently (which is why I think it is crappy). Today I am having the typical problem: The saw starts OK, but to keep it running I have to 'goose' the throttle constantly, alternating between about half throttle and almost full throttle. i can't get the saw to run with any steady throttle setting, not full, not half, and sometimes not even idle. Any ideas how to remedy this problem?

When it occasionally runs well, I think this isn't a bad saw. it is smaller, with a 16 inch bar, but it cuts most of what I scrounge pretty nicely. Not bad for a cheap saw if it would run.

 

[MasterMech]

I have a crappy homelite chainsaw that has never run consistently (which is why I think it is crappy). Today I am having the typical problem: The saw starts OK, but to keep it running I have to 'goose' the throttle constantly, alternating between about half throttle and almost full throttle. i can't get the saw to run with any steady throttle setting, not full, not half, and sometimes not even idle. Any ideas how to remedy this problem?

When it occasionally runs well, I think this isn't a bad saw. it is smaller, with a 16 inch bar, but it cuts most of what I scrounge pretty nicely. Not bad for a cheap saw if it would run.

If the saw doesn't respond well to the usual carb adjustments then I'd start looking for air/vacuum leaks.

 

[Wood Duck]

I have a crappy homelite chainsaw that has never run consistently (which is why I think it is crappy). Today I am having the typical problem: The saw starts OK, but to keep it running I have to 'goose' the throttle constantly, alternating between about half throttle and almost full throttle. i can't get the saw to run with any steady throttle setting, not full, not half, and sometimes not even idle. Any ideas how to remedy this problem?

When it occasionally runs well, I think this isn't a bad saw. it is smaller, with a 16 inch bar, but it cuts most of what I scrounge pretty nicely. Not bad for a cheap saw if it would run.

If the saw doesn't respond well to the usual carb adjustments then I'd start looking for air/vacuum leaks.

Humor me - I don't know much about chainsaws. What are the usual carb adjustments?

 

[MasterMech]

It varies from saw to saw but there should be factory adjustments for the mixture screws in your owners manual. Newer saws have limiter caps on the screws to prevent the screws from being adjusted too far from factory settings. Most common thing I get with saws that run fine but will not idle for more than a second or two, is the idle stop screw backs out over time. It's the one that holds the throttle plate cracked open just a bit to allow the saw to idle. You mentioned that it acts up at all RPMs, hmm, check the fuel supply line from the tank to the carb for pin holes/cracks, may be cheaper/faster just to replace it. Otherwise could be air leaks from a loose carburetor, leaking gaskets in the intake/carb stack, internal issues in the carb such as a stretched diaphragm or debris packed inside, or leaking crankshaft seals.

 

[Wood Duck]

I wanted to cut today so the first thing I did was check the carb adjustments. My saw has two small, deeply recessed, square head screws that seem to be the carb settings. I can barely even see the screws and have no idea how to just what setting they might be on, let alone smoothly adjust them, since they seem to require small, thin-walled square sockets that I don't have. So, the only thing I could do was try to adjust the high screw with a screw driver - there is no slot for a screw driver in the head of the screw, but a screw driver is about the only tool I have that will reach into the narrow hole where the screws are located. I tried to turn the screws, but it didn't seem like I was able to move them at all.

Nevertheless, it worked great. I guess I changed both the low and high settings, since now the saw idles at a pretty high speed and at full throttle it runs well. it really isn't adjusted correctly, I am sure, but at least now I can cut with it.

What tool is the right one for this job of adjusting the carb settings?

 

[HittinSteel]

You need a special screwdriver to adjust those .....do you have a decent dealer in your area? They may adjust it for you at a reasonable cost. Most likely your Low speed needs richened and then your idle adjusted.

 

[Wood Duck]

I don't know of a good place to have the saw adjusted. There is a small engine repair place nearby, but they take a week or so to get around to fixing things so it is not convenient, and the carb seems to be back out of adjustment in an hour or two. I need to be able to adjust things myself.

 

[HittinSteel]

This is likely what you need........

http://www.ebay.com/itm/New-OEM-Spe...592?pt=LH_DefaultDomain_0&hash=item23146c6d78

A word of caution though, find the operator's manual online and find out which is the H and which is the L screw for sure and what the standard setting is (likely 1 full turn out from lightly seated). With the saw turned off, I would turn both the H and L screw clockwise until they seat (lightly, don't keep turning them once they seat or you will damage the needle ends). Then back each screw off, counterclockwise to the standard setting. I'd then go about an 1/8 to a 1/4 more counterclockwise. This will simply richen your mix. DO NOT under any circumstances turn either the H or L clockwise from the standard setting. This could lean the saw out and it may burn up.

Next would be to mess with your Idle screw (sometimes marked T or LA). With the saw running, turn it clockwise until the chain starts to move and then back it off counterclockwise an 1/8 or 1/4 turn. You may now need to fine tune the L screw......either clockwise (but again NEVER past the standard setting) or counterclockwise until the saw accelerates smoothly. The H may also need to be adjusted and should be done with a tachometer, unless you are comfortable with what "4stroking" sounds like.

Here is a much more descriptive tutorial, complete with wave files to let you listen. http://www.madsens1.com/saw_carb_tune.htm.

This is saw tuning 101. I learned to tune on a Poulan Wild Thing. I figured if I messed up, I wouldn't be out much. I eventually ended up giving the saw after a muffler mod and retune to a buddy who absolutely loves the saw for his small woodcutting tasks.

 

[MasterMech]

Special tool is (drum roll please... ) Husqvarna Part #530 03 55-60

 

[wkpoor]

Proper tuning isn't something you can learn from a book. You have to know what lean and rich sound like. Find someone who knows how to tune and get some dual time. Learning 2 cycle tuning is almost a prerequisite to running a chainsaw. I have been operating a chainsaw for over 25yrs and still had something to learn from the masters when I got into hot saws.

 

[Singed Eyebrows]

As was mentioned, you won't do much tuning if there are leaking crank seals. If speed changes if you tip the saw on it's sides when idling chances are they are worn out. Randy