have a moderately used 261, regular carb that does not want to rev above 9000. when it started to run run out of fuel it when up to about 13,000 for a second or two before dying. new plug, tried removing the air filter - no change. removed carb and did a light spray with cleaner, no change. high speed screw does seem to change anything from 3/4 to 1 1/2 turns out. suggestions very welcome at this point, TIA
261 does not rev
- Thread starter striperswaper
- Start date
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Fuel tank vent, fuel filter, fuel line, dirty carb.....
if the problem is fuel delivery as in vent, fuel line and filter, why would the saw run better/higher rpm as it runs out of fuel?
It's running lean.
I understand the rpm increases as the mixture leans out. can't adjust the carb lean enough to get the rpm where they should be. that is the problem as it appears to me. why it appears to be rich? that is the question or problem
Seems the problem is its running too rich, and only when it runs out of fuel, and finally leans out some, it increases in rpm.
You have some good advice, so work thru it step by step.
My advice, is to check whats already been mentioned, if your not sure how to check each thing, then ask.
if its got some hours on it, when was the last time it had a carb kit in it. ?
could be some leaking fuel past the needle, running too rich, stiff metering diaphragm usually causes other issues, but hey, could be an issue here.
The fuel pump diaphragm and its one way valves can go stiff in operation, or not seal over the body of the carb on the drillings, all can contribute to it.
would suggest getting a new carb kit go gen stihl, and fuel filter whilst your there, and go from there.
Have a good look inside, make sure the needle seat is not scored, or dirty with dried up/ fuel resin, which can also contribute to a needle not sealing well.
Lets go step by step thru this and fix it.
You have some good advice, so work thru it step by step.
My advice, is to check whats already been mentioned, if your not sure how to check each thing, then ask.
if its got some hours on it, when was the last time it had a carb kit in it. ?
could be some leaking fuel past the needle, running too rich, stiff metering diaphragm usually causes other issues, but hey, could be an issue here.
The fuel pump diaphragm and its one way valves can go stiff in operation, or not seal over the body of the carb on the drillings, all can contribute to it.
would suggest getting a new carb kit go gen stihl, and fuel filter whilst your there, and go from there.
Have a good look inside, make sure the needle seat is not scored, or dirty with dried up/ fuel resin, which can also contribute to a needle not sealing well.
Lets go step by step thru this and fix it.
I think it's a fuel supply issue. Either way, going over the fuel system isn't hard to do. Make sure you set the metering lever to the correct height, or just reuse the old one. They don't really go bad.
