This saw never did respond quickly to throttle opening. It starts easily ,idles well, cuts good, but now its worse than ever getting up to working rpm, without at least 5/6 squezzes of the trigger. I have replaced the fuel,air filter. The plug is tan color (Help)
Echo CS-370 Throttle Response
- Thread starter fayjim2
- Start date
1.Flywheel key check.
2.Pressure test carb, tank and lines.
3.CLEAN exhaust port and remove that pesky window screen slash forest fire maker.
4.Most likely issue, replace the carb with OEM. Or clean the old and rebuild that little fella'.
5.LOAD test the ignition coil.
2.Pressure test carb, tank and lines.
3.CLEAN exhaust port and remove that pesky window screen slash forest fire maker.
4.Most likely issue, replace the carb with OEM. Or clean the old and rebuild that little fella'.
5.LOAD test the ignition coil.
If a two stroke engine is not running properly don't use it you can ruin the engine. If it is running lean it can do piston and cylinder damage, as a lean condition causes the engine to over heat from lack of lubrication. Your problem is probably due to the main metering diaphragm getting hard and brittle and not flexing like it should. The diaphragm works like a float in a bowl type carb. and it needs to flex freely. If it gets hard and brittle it does not flex like it should it will cause it to run lean. It also has a fuel pump diaphragm it has two flapper valves and a pulse area. Crankcase high and low pressure acts on the pulse area and draws fuel into the carb buy way of two flapper valves an inlet and an exit that work in conjunction to work as a pump. If it is not working properly it will not pump fuel into the main metering chamber like it should and can cause hard starting and a lean running condition. Get it fixed.
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The problem with new equipment [especially 2 two cycles] is that no one ever tune them before delivery. Most are setup with a will start settings and usually run fairly well. With 2 cycles as the metering diaphragm stiffens the problem of improperly tuned engine become more apparent. Plus most Echo equipment are fairly lean even when tuned correctly which is why they take up to two minutes to warm up to operating temperature. Otherwords they are sluggish when first started. But when they warmed up the throttle response should be fairly good on a properly tuned engine. This is even when the saw idle mixture is tuned rich per Echo instructions. Plus the high speed may need to be slightly enrich to keep engine from exceeding max allow rpms.
Tuning these engines do require a tachometer and an EPA plug removal tool. This should be done by a professional 2 cycle tech that has the Echo tuning instructions and tools. And that tech should also check the metering lever height as many are not set correctly from the carburetor factory.
As HLW49 posted you can destroy an engine that is not properly tuned.
It also doesn't hurt to have a properly sharpen chain in use. Most homeowners will use a chain so dull that you could slide backwards down it and probably only get a scratch. Then when they burn up a bar bitch like crazy that saw is a piece of junk when in fact it is just needing proper maintenance. Nearly every chainsaw that comes into my shop has to have the chain sharpen or replaced.
Tuning these engines do require a tachometer and an EPA plug removal tool. This should be done by a professional 2 cycle tech that has the Echo tuning instructions and tools. And that tech should also check the metering lever height as many are not set correctly from the carburetor factory.
As HLW49 posted you can destroy an engine that is not properly tuned.
It also doesn't hurt to have a properly sharpen chain in use. Most homeowners will use a chain so dull that you could slide backwards down it and probably only get a scratch. Then when they burn up a bar bitch like crazy that saw is a piece of junk when in fact it is just needing proper maintenance. Nearly every chainsaw that comes into my shop has to have the chain sharpen or replaced.