blower vibration on at wide open

[xxl]

I have had my echo 755 bp blower and noticed a power loss one day that it would not rev up to anyware close to what it used to. Checked the exhuast port and screen clean and clear. Then i changed carbs worked for it and ran great but now has developed a vibration at high power like the fan is unbalanced any ideas on what to check?

[viper00085]

could have a crank brg or internal engine issue happening causing the vibes and drag (loose of rpms/power)

also I cant remember if it was 650's or 650-755's but echo did have some issues with fan bolts coming loose from the flywheels that they mount to and causing your symptoms. Does the engine feel weird (like its gonna kick back or has high compression) or any different while trying to pull start it than what it used to? If you do find this is the issue when you order a new fan or flywheel it comes as a kit with both parts and its decently priced for a echo part :-)

[xxl]

checked the fan bolts tight as can be. feels the same when i pull the rope the weird thing is it happens after 5 minutes of running then it develops the vibration