Service & Maintenance Question
455 chainsaw dies when throttle is wide open
,was running...
Service & Maintenance Question posted September 15, 2014 by john schindler
212 Views, 13 Comments
Question:
455 chainsaw dies when throttle is wide open
,was running good when chain slipped off bar. after refitting and adjusting chain, saw is chocking down and dying when throttle is fully opened
,was running good when chain slipped off bar. after refitting and adjusting chain, saw is chocking down and dying when throttle is fully opened
Average Rating:
100% (+1/-0)|
-
Answer
john, from the brief narrative it sounds like the brake band is biting into the clutch drum. check it carefully along with the clutch condition. after removing the cover, activate the brake and release it while evaluating the function. also the big spring behind the plate and bar bolts. I can't imagine how but it may have been impacted. those things are where I would investigate 1st.
good luck, let me know what you find...
Be the first to rate this
|
When I took off the cover, the brake band was indeed biting into the drum. leaving the cover off and checking the filter, it was dirty. I left it off also and started the chain saw. Same thing happened. I was able to observe the air intake. As soon as it started to open the saw started to chock back. When it was fully open, the saw died
Be the first to rate this
|
please look at the impulse hose and make sure it is connected. it has vacuum and the end that comes out of the crank should hold vacuum. next thing I need is to know is if you have been using fuel with ethanol. ethanol dissolves the black rubber hoses and allows small chunks to flow into the carburetor.
Be the first to rate this
|
ethanol is definitely a bad idea. but 1st what is happening with the clutch and brake band? was there damage? and when you say the band was indeed biting into the drum, was the brake lever on, or off? you must 1st make certain the clutch brake and clutch are in order. if any damage occurred when the chain jumped you have to identify it. I need more info so that I can try to help.
Be the first to rate this
|
when you say the band was indeed biting into the drum, was the brake applied or released? if any damage was done when the chain jumped, it must be identified. the clutch inspection is important as well. the shoes and springs should be engaged by the driveshaft, but the drum should free wheel on the needle bearings smoothly. those bearings are very important and should be in-tact and functional. after you get past the clutch area, I need to know if ethanol is being used in that fuel system. ethanol will destroy those hoses and allow small chunks to get sucked into the carburetor. hopefully, that will not be an issue. if it is, then carb comes off and gets thoroughly cleaned out. and hoses replaced. the impulse hose must be clear and unobstructed for vacuum. I need more info to try to help you.
Be the first to rate this
|
The chain rides easily on the bar when pulled. I've checked the brake, bands and sprocket. There doesn't appear to be any damage. Now for the ethanol. the mention of that word sends my body into epileptic fits and results in a great loss of sleep trying to figure how anyone could have put that curse onto mankind. I don't use it in any of my 2 cycle engines. But I bought this from tractor Supply, supposedly reconditioned. Because this problem made me examine the "inside the cover" area, I can assure you their reconditioning consisted of no more work than cleaning the outside. I can also assume that the person who returned it to Tractor Supply doesn't have a clue as to the nature of ethanol. I bought a 3 year warrantee at the time of purchase and am thinking their warrantee might be a joke. I called the repair shop I was given. The mechanic said it sounded like a piece of dirt might have gotten into the high speed jet. He told me the warrantee didn't cover carburetor work and one needed a special tool to adjust the jet. This lends itself to Bob's comment about the deterioration of the hoses.
Be the first to rate this
|
John, and Robert,
I am guessing that there is something wrong with the clutch and brake.
Can you pull on the chain with a pair of gloves on in the direction of the normal chain travel, and does the chain move freely?
If it does not, I would check out the brake as robert suggested, If you need help checking it or testing it, just give me a shout, and I will be glad to try and help.
PS. I am Not a Husqvarna Representative or Authorized Repair, just an experimental chainsaw person
Be the first to rate this
|
I've posted 2 comments to your answers, but I don't see them. Have you seen them?
Be the first to rate this
|
if you think all is well in the clutch and brake area then its good enough for me. as long as there is no wobble with the drum on those needle bearings. when the chain jumped, that is when this problem started, but that could just be a coincidence.
now, lets try this. assuming you have a good blowgun with a narrow aggressive hosel, and a compressor, remove the spark plug and the CRV from the top of the jug. blow it out at TDC and at the bottom of travel. open the choke gate and blow thru the carburetor trying to bust any FOD loose. now blow out the jug once again. blow out the fuel tank then use hemostats or a hookpic to pull the fuel line out. remove the fuel filter off of the hose, unless you know for sure its okay. now use a paint strainer to refill the tank after stuffing the fuel line back in. this is for testing only. the filter must be replaced/reinstalled b-4 you go cutting. replace the spark plug and the CRV and fire it up.
lets see what happens...
Average Rating:
100% (+1/-0)
|
Thanks, I'll try this first thing in the morning.
Be the first to rate this
|
I did as you suggested. The fuel lines and filter are in good shape. I used the air nozzle. It now runs great, no hesitation. Thank you for your help, John
Be the first to rate this
|
just on the outside chance any gum is accumulating, douche the carb with carburetor cleaner and allow it to soak in for about 15-20 minutes. then blow it out well.
Be the first to rate this
|
okay brother, you are welcome. we lucked out and found it quickly. congrats. now just keep it clean and be careful...
Be the first to rate this
|