Hi everyone,
I have owned this trimmer for about 2 years now. It has had a very easy life. Regular use but only about 20 mins per time. I always let it warm up for a few minutes and use Stihl premium synthetic oil 50:1. It has probably had about 15 hours use in total. It has been a great trimmer until last week. I started it and found that it wouldn't reach WOT. It was running ok though and after a few minutes seemed to come good. A few minutes later it started cutting out at idle. I could not get it to keep idling even after it had cooled down and was restarted using choke. I check plug, spark arrestor, air filter. All good. I took the carby apart and cleaned it. It now runs better but haven't had a chance to give it a good run yet.
This is because I found that the black plastic rotor seems to be binding against the housing. This is now causing it to hang and not return to idle under the tension of the spring like it should. I don't think it was doing this before I cleaned it. I have pulled it off and put it back on several times and taken it apart and cleaned. I can't see that I'm doing anything wrong as it just pushes into the housing and 3 screws hold it in place. I have lubricated around the barrel with 2 stroke oil and put some grease under the rubber cap thinking that I may have removed its lubrication during cleaning. It still seems to catch but only sometimes now. When it catches, if you flick it up vertically with a screwdriver it frees up and flicks back to its base position so it seems to be the bottom of the rotor binding against the bore.
Has anyone experienced this problem?
When looking around the net for info on this carb I found many many threads where people were rubbishing these Zama RB carburetors. I read somewhere that in some markets they were replaced with Walbro carbs.
Are these carbs really that bad?
The rest of the trimmer seems to be very well made.
I have owned this trimmer for about 2 years now. It has had a very easy life. Regular use but only about 20 mins per time. I always let it warm up for a few minutes and use Stihl premium synthetic oil 50:1. It has probably had about 15 hours use in total. It has been a great trimmer until last week. I started it and found that it wouldn't reach WOT. It was running ok though and after a few minutes seemed to come good. A few minutes later it started cutting out at idle. I could not get it to keep idling even after it had cooled down and was restarted using choke. I check plug, spark arrestor, air filter. All good. I took the carby apart and cleaned it. It now runs better but haven't had a chance to give it a good run yet.
This is because I found that the black plastic rotor seems to be binding against the housing. This is now causing it to hang and not return to idle under the tension of the spring like it should. I don't think it was doing this before I cleaned it. I have pulled it off and put it back on several times and taken it apart and cleaned. I can't see that I'm doing anything wrong as it just pushes into the housing and 3 screws hold it in place. I have lubricated around the barrel with 2 stroke oil and put some grease under the rubber cap thinking that I may have removed its lubrication during cleaning. It still seems to catch but only sometimes now. When it catches, if you flick it up vertically with a screwdriver it frees up and flicks back to its base position so it seems to be the bottom of the rotor binding against the bore.
Has anyone experienced this problem?
When looking around the net for info on this carb I found many many threads where people were rubbishing these Zama RB carburetors. I read somewhere that in some markets they were replaced with Walbro carbs.
Are these carbs really that bad?
The rest of the trimmer seems to be very well made.