General Product Question
450 Chainsaw, 20 inch bar/chain, power issues
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General Product Question posted October 27, 2014 by Terry Sanders
65 Views, 2 Comments
Question:
450 Chainsaw, 20 inch bar/chain, power issues
Starts great and cuts great on anything under 10 inches in diameter. However, whenever I try to cut anything larger (red/white oak), saw bogs down heavily and often dies, especially when I pivot and try to use any forward part of the bar. Have owned a 455 Rancher and was always pleased with its performance. Have owned 450 for about 2 months now. Seems gutless. Suggestions? Since there is no adjustment allowed for H jet any longer, I can't try to tweak myself.
Starts great and cuts great on anything under 10 inches in diameter. However, whenever I try to cut anything larger (red/white oak), saw bogs down heavily and often dies, especially when I pivot and try to use any forward part of the bar. Have owned a 455 Rancher and was always pleased with its performance. Have owned 450 for about 2 months now. Seems gutless. Suggestions? Since there is no adjustment allowed for H jet any longer, I can't try to tweak myself.
Answer
the limiters can easily be removed but I don't recommend doing so. if the saw idles okay, and has instant throttle response toward wide open, then the carb jet needles are not the issue here. always use wedges when attacking larger work, the chain needs to be sharped accurately. I can't be certain of cause without witnessing the event. does it smoke? too much oil in the mixture or too rich a mixture if so. elevation? if not high elevation it could be excessive heat robbing optimum compression because it is too lean and getting too much air vacuumed in thru the carb. I suggest you pull the plug and compression test for a value. if you don't have a compression testing kit, sears sells a nice set for $65.00 or so. any number 140psi up is plenty compression. check intake boot for a crack. if there is a crack then it is sucking in too much air making the mixture dangerously lean. that would overheat the jug and cause a loss of compression at the time work is most demanding... give more background info and I will assist in resolving this issue...
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Terry,
I know you said that you have only had the Model 450 for two months, but did you buy it brand new, used or refurbished ? If it was purchased used or re-furbished, I would probably suggest taking the muffler off and looking inside the cylinder at the condition of the piston, and piston ring, and during your inspection make sure there is no scoring on the internal parts of the engine,
I would also check the fuel filter in the tank, even If it is new. The fuel filters can varnish over very easily (Note: they will change color from a pristine white to a yellowish or brownish color ), I usually just replace them before I start troubleshooting a chainsaw just to eliminate that possibility, but yes it will give you the exact symptom that you have which is it will start fine, idle OK, and then when it gets underload at full throttle it bogs down.
They are easy to replace, and fairly reasonable, make sure you are using the correct fuel filter for a 50 cc engine, if someone put a smaller filter in the tank that could be a problem too. I also always dump the fuel out of a chainsaw that I am troubleshooting, and mix up a fresh batch of fuel just in case someone left 2-3 month old fuel in the chainsaw, so I would also suggest making sure the fuel is as fresh as possible, or pick up a can of pre-mix and try that with a new filter.
I hope this helps
Karla
PS. I am Not a Husqvarna Representative or Authorized Repair, Just an Experimental Chainsaw Person.
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