McCulloch CS420t....issues

[raindogred]

Hi guys,
It starts and idles fine with brake on. The problem is when the brake is off, the chain spins madly then it cuts out when you press throttle. I think if i let it idle and warm up for a while, can get it to run ok. I took the bar off and started it...same issues. There is 3 adjustment holes ..T-idle screw, H and L.....I don't have a tool for H and L, but i messed with idle screw....took it all the way right then went anti-clockwise a full turn...tried going way down anti-clockwise a few more turns incrementally...doesn't make any difference....i did notice that for a split second it seemed to stop the chain spinning when idling, but as soon as the throttle pressed...spins madly again. Talking with chat GPT and reckons to check the "clutch shoes"...what are they and could that be the issue???? This saw cost me $100 on market place, the guy started it up...me being a newb, thought "you beauty" it runs and took it. I'm using an corded electric in my yard, which is working well..but I would like to get this mcculloch running...if only as a learning excercise in understanding 2 stroke devices better.#repairs

 

[Bob Hedgecutter]

Buying plastic consumer grade saws second hand always comes with risk- they are often "damaged" and an uneconomic repair- part of the throw away modern era.
Your idle screw is not a jet adjusting screw- it does NOT have a base setting of lightly seated and out one turn.
The idle screw simply tapers against the throttle plate lever and the further in you go, the more open the throttle is.
If you cannot start the saw and back off the idle screw to a point where the unbraked chain stops rotating around the bar- odds are you have an air leak in the system- probably a loose engine pan or crank seal issue.

 

[raindogred]

yep its a throwaway then. i don't have much money, and i can't keep buying chainsaws....wish i knew more about them...are there affordable options out there that you could recomend...any makes and models...I'm in Australia...probably lots of models aern't common place here, as in other countries?? the electric is ok, and i bought a mini battery one hand thing, which is surprisingly good. I need a petrol machine, as i just can't see how the electric corded will go while working off 16 foot trestles pruning mango trees in my yard. I have already knocked a few trees over, the cord gets very annoying. I have some palms to chop down, mango trees to prune, and a couple of unknown species to bring down i would need an 18 inch bar...one tree is as high as the power line...after this project I won't be doing much chainsawing...i just need something that will cut the above mentioned. I see these cheap chinese machines on ebay at crazy prices "giantz brand"...are they not worth the the low price they are asking?? Also I have had a look at a mob called edisons who sell baumr ag brand, which i have had a bit of luck with one of their line trimmers which ran great for a couple years, but went under the floods in 2022, ended replacing with an echo with insurance money.. any info appreciated Bob

 

[Bob Hedgecutter]

So you live on our Western Island then?
Saw brands and types are pretty common between us.

If you do not have a whole lot to do- hiring a saw that suits is a possibility.

Same old same old with tools- you generally get what you pay for- if its cheap, it usually is not as good as something dearer.
If you dont know the pitfalls, or what to look for/look out for- buying secondhand is a risk and a gamble.
You mentioned Echo trimmer- they do some pretty good reasonably priced chainsaws as well.