D eez: What do you think has happened DonyBoy73? Anyone else have any ideas?
What and where does the contact occur that causes scoring on the piston; below the ring?
BeaudreauBell1141 (1Year ago) suggests engine is running to lean and in turn exhaust gases get hotter and then the aluminum piston goes(I guess he means it gets scored) but he also kind of mentions that the “PISTON RING” often gets seized in its groove.
"I think" this “Seized Piston Ring” scenario makes the most likely cause because if ring is seized in its groove, (likely due to carbon buildup) it stops the piston from being centered and when ring wears away on part of its area the piston will rub on the cylinder wall along with metal shavings and carbon. I think this is the likely cause because I recently took apart a Poulan where all the evidence pointed to the Seized Piston Ring in its piston groove.
Adam Luna: I have the 346xp but after first 2 logs I cut I start getting some oil burn smoke on my chain and then the chain goes dull and lots of smoke coming from the chain bar. What could be my problem? Thanks
Shaun Victor: I just purchased a used Stihl 026 and its running right at 140PSI and it has no scoring whatsoever and it runs great.140 is not really a low reading.When you pushed the piston around inside the cylinder that was weird.That top end is not going to live long,thats for sure. You should pull it down and see if the cylinder is worth salvaging and maybe get away with a new piston and ring. Would like to know how it all works out. Interesting video,thx.
mooch1441: Ok I just thought if I did sell it I would notify the buyer way before hand. I have two other older lawnboys and have also thought about using it for parts. What would you suggest?
donyboy73: I prefer not selling things with know defects
mooch1441: Donyboy I have a older 2 cycle lawnboy and the piston is very scored. It has about 90 PSI but still runs ok. I was thinking about selling it before i saw the scoring. Do you think I should still sell it?
donyboy73: very possible
Xxpoison99xX: I put an expansion chamber on my saw off an 83 rm80 and it runs waaaaaay faster
Xxpoison99xX: Could a lightly scored piston score a cylinder?
cyrus romer: I have a super xl homelite chainsaw and the piston has scoring on the bottom side of the piston and the piston is loose in the case is that bad but it runs fine
KxFanyboy 111: How much psi should a tecumseh lawnmower have?
cyrus romer: Thanks I'm going to kahlers to buy a bolt but man there expensive 1.42 for one bolt
donyboy73: SOUNDS LIKE THAT IS YOUR PROBLEM
cyrus romer: I have a 345 that won't start it has spark and good compression but there is scoring on the intake Side but none on the exhaust side I noticed a bolt missing on the underneath the motor could that be the problem not enough back pressure
cyrus romer: I have a 345 chainsaw and it won't start and there is scoring on the intake side but I noticed that its missing a bolt underneath it could that be the problem why it won't start
donyboy73: i know but i just don't have time to keep up
Antonio Araiza: Thank you for all your videos, I learn too much from you to keep my tools in good shape. Hampton, VA
TheDurnans: I use 87 octane non ethanol petrol and I mix it a little rich. I use a 2.5 gallon mix jug and mix it to 2 gallons of gas. I've seen saws fry before while using the "correct" 50:1 mix, so I'm a little hesitant to run a true 50:1. To be honest, i really don't know how to properly adjust the carbs on one of these saws. I'd be afraid to lean it out to much and burn it up that way.
TheDurnans: I just bought a 346XP ETech - not my choice to have the cat muffler, but was told all new 346s are cat muffled now. Mine runs hotter than a pistol and I haven't adjusted any of the screws on it since I bought it a little over a month ago. When it's good and hot, it doesn't like to stay running and is very hard to start. You can see the heat come off this saw after cutting oak when it's 70+ outside. I'm afraid I'm going to fry my saw! I'm running the XP oil as well.
donyboy73: should be
Shrimps: Thanks man, I appreciate the feedback. The reason I was able to get sales is because I offer rare shrimps for sale. Not many other online place is willing to take the risk at shipping high priced shrimps. That is my way of earning online.
Husqvarna 346xp Chainsaw Scored Piston Compression Test & Startup5
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