Husky 450 in idle revving up an down without touching gas
- Thread starter Pepe
- Start date
This is one of the "new" Husqvarna types that I do not have a lot to do with- but an educated guess would be a massive air leak.
I am also guessing this is the same 450 that is dropping oil out of the recoil starter side, so my next guess is the cases are cracked broken at the base somewhere- allowing oil out of the tank and air into the crankcase bottom.
Removal of the rear handle/fuel tank assembly should allow you to check, or it could be under the recoil starter and flywheel areas.
Could be the saw has been somehow damaged enough to crack the oil tank and maybe loosen or tear the threads on the four bolts that hold the cylinder down on the plastic pan, so the air leak could be a separate issue to the oil leak- or they could be associated.
My own method of detection would be a teardown and inspect- repair and replace the obvious, rebuild and pressure/vac test to ensure repairs are good.
Looking at an IPL (illustrated parts list) for your model saw will help explain what fits where, how it comes apart and what might be at fault.
I am also guessing this is the same 450 that is dropping oil out of the recoil starter side, so my next guess is the cases are cracked broken at the base somewhere- allowing oil out of the tank and air into the crankcase bottom.
Removal of the rear handle/fuel tank assembly should allow you to check, or it could be under the recoil starter and flywheel areas.
Could be the saw has been somehow damaged enough to crack the oil tank and maybe loosen or tear the threads on the four bolts that hold the cylinder down on the plastic pan, so the air leak could be a separate issue to the oil leak- or they could be associated.
My own method of detection would be a teardown and inspect- repair and replace the obvious, rebuild and pressure/vac test to ensure repairs are good.
Looking at an IPL (illustrated parts list) for your model saw will help explain what fits where, how it comes apart and what might be at fault.
Not sure we can link youtube videos direct here, but pretty sure Matthew Olsen has a bolt by bolt video on a 455 which should be close enough for you.