jdhupp
ArboristSite Lurker
This actually concerns a Stihl TS 400 cutoff saw, but I'm sure the list of possible causes would be similar to a chainsaw.
This saw starts with 2 pulls with choke on and then 2 pulls with choke off. It runs OK with some throttle, but it will die right away if I try to let it idle, and that is the case if the saw is hot or cold.
There are two carb adjustment screws, L low speed (coarser) adjustment and LA idle speed (finer) adjustment, but I find that even the main L screw adjustment has no effect on the problem. Standard setting is one turn out, but I can go to three turns without touching idle performance.
A second problem is that acceleration is sluggish.
I'm in the process of replacing a slightly cracked fuel hose (the tank to carb hose, not the carb to cylinder hose), but I'm not sure the cracks are enough to cause this problem.
If replacing the fuel hose doesn't fix it, what are my other likely suspects?
The spark plug is almost new and looks clean. And I have just rebuilt the carburetor (though I did not soak it in carb cleaner, just flushed with gas and installed the kit parts), replaced the in-tank fuel filter, and replaced the missing auxiliary air filter (and blown out the other two air filters) and missing spark arresting screen in the muffler. Prior to doing those things, I could get the saw to idle for a while by setting the L screw a little higher than it was supposed to be, but it would eventually die anyway after idling erratically. And it also had the poor acceleration at that point. I was imagining that the idle problem got worse because I fiddled with the fuel hose some while removing/replacing the carb.
This saw starts with 2 pulls with choke on and then 2 pulls with choke off. It runs OK with some throttle, but it will die right away if I try to let it idle, and that is the case if the saw is hot or cold.
There are two carb adjustment screws, L low speed (coarser) adjustment and LA idle speed (finer) adjustment, but I find that even the main L screw adjustment has no effect on the problem. Standard setting is one turn out, but I can go to three turns without touching idle performance.
A second problem is that acceleration is sluggish.
I'm in the process of replacing a slightly cracked fuel hose (the tank to carb hose, not the carb to cylinder hose), but I'm not sure the cracks are enough to cause this problem.
If replacing the fuel hose doesn't fix it, what are my other likely suspects?
The spark plug is almost new and looks clean. And I have just rebuilt the carburetor (though I did not soak it in carb cleaner, just flushed with gas and installed the kit parts), replaced the in-tank fuel filter, and replaced the missing auxiliary air filter (and blown out the other two air filters) and missing spark arresting screen in the muffler. Prior to doing those things, I could get the saw to idle for a while by setting the L screw a little higher than it was supposed to be, but it would eventually die anyway after idling erratically. And it also had the poor acceleration at that point. I was imagining that the idle problem got worse because I fiddled with the fuel hose some while removing/replacing the carb.
