20 Most Recent Husqvarna , No.455 Rancher, 20" Gas - Powered Chainsaw - Page 5 Questions & Answers

Check the fuel tank vent, ive had 455 and a 450 rancher in for repair that have had the same symptoms. Sometimes it can be the breather pipe that has come off the carb, ive had that happen on a 395xp. The vents are simple to change and it sorted out the problem on both saws. 1 was simple to spot as it leaked fuel when laying on its side.

try using the de-compression button when starting, will do the same as removing the spark plug but without removing the spark plug.Failing that, remove the starter cover and check starter cord for daage or signs of snagging.

Sorry but the only true way is to put the unit on the machine, set the air gap to 0.3mm diss connect any wires on the unit that go to the switch, assemble the starter, use a new plug or spark tester with a wide gap, earth well against the cylinder, crank the engine as if you were going to start it, if there is a spark the unit is ok, if not then its bad. There are expensive testers on the market, but if the unit does not spark on the saw what is the point of testing it.

check the carburetor. If you have a stiff diaphragm then it won't run.I have seen them that behave just like that. They will run fine, turn it off for a few minutes then they won't restart. WD40 isn't going to get it to run either, try a small amount of mixed gas right into the carb. It should run for a minute until the gas you put in runs out then die. If it doesn't run then you have a bigger problem If you need further help, I’m available over the phone at https://www.6ya.com/expert/kelly_69a0cf1b13789df1

You need to pull the muffler off and check the condition of the piston throught the open exhaust port, if there is signs of damage or scuffing, the machine will have to come apart for further investigation, water can act as a catalyst and part the two stroke oil from the petrol, the saw will normally stop if there is a large amount of water in the tank before any damage is done, washing out the tank and refilling with good fuel normally sorts them out.

There are two needle screws that can be adjusted to make the engine run properly. Be certain that the carburetor is clean and the diaphragm is in good condition, and the fuel is new. The two needle screws mentioned above should initially be adjusted at one turn open from turned in all the way (lightly seated). Each of these needle screws performs different functions. One is for idle and throttle response (this screw is marked "L" and the other screw is marked "H". L and H are marked on the carburetor body and also on the plastic "shroud" near the adjustment screws. These screws are not interchangeable, being foolproof since the thread sizes are not the same. When properly adjusted the low speed screw (L) allows the engine to idle properly and throttle response will work properly. When the high speed screw is adjusted properly the engine will have correct power at full speed. Adjust the low speed screw so that the engine idles and when you squeeze throttle all the way to wide open the engine should not hesitate and should come up to full speed and when you drop the throttle it should idle nicely without stalling. Now adjust the high speed screw. Hold throttle wide open, holding it there while you adjust the high speed screw. If this scares you (be carefully so that the spinning chain does not cut you!) you may adjust the high speed screw at idle, turning it just slightly in or out. The high speed screw should be adjusted so that the engine does not run clean at wide open throttle but sputters slightly, slightly adjusted open from running clean to slightly sputtering. When under load (cutting a log) the engine should run clean. Good luck!

The piston ring opening should have a spot on the piston with a little nub to align it. If it doesn't then just make sure the ring openings do not line up together. As for putting the piston in, there should be a mark on the top that will go toward the exhaust side If you need further help, I’m available over the phone at https://www.6ya.com/expert/kelly_69a0cf1b13789df1

The piston crown will have an arrow on it if you clean the carbon off, the arrow always goes towards the exhaust port which puts the ring peg at the inlet.

Sounds like fuel starvation, always start with simple things first, replace the fuel filter in the fuel tank, check the fuel hose up to the carb for signs of leaking.

Also make sure that where the oil is pumped against the side of the bar that the oil port (little hole) that feeds oil into the bar's slot is clear. Mine would go through a tank of oil with each tank of gas, but the chain wasn't getting oiled until I cleaned out this little hole.

you need too adjust the high jet ccw (making it richer) do do that takes a little work cause you need a special tool but I can help you around that if you like. let me know

what is the chain angle for the 460 chain using the electric sharpener

Faulty crankshaft oil seals.

hi

check the fuel filter,clean the gas tank,the carburator ,check the fuel pump(not to be tired).the fine filter inside the carb under the fuel pumpand the sparkplug.

by for now savumihai71