Chainsaw Repair
Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Husqvarna => Topic started by: John Mc on March 06, 2013, 10:13:22 am
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A friend of mine may have just fried his 353. I don't know the damage, and I haven't seen it. The only report I've heard is "repair guy says compression is shot. When asked for a probable cause, he says ethanol gas may be a prime suspect, he says a number of saws have come in with similar symptoms." (I wonder if may have been run too lean?)
I'm trying to convince him to examine the possibility of replacing piston and rings, and maybe cylinder, depending on what it looks like. Neither of us have done this sort of work before, but he's fairly mechanically experienced.
If it's not worth repairing, is the 545 about the closest replacement in the Husky line these days? He'd probably go for that over something in the 400 series (like a 450 or 455). I can read the specs, I just want to make sure he's not stepping down in capability/durability.
If it helps for background: He's used his 353 for about 5 years of "landowner"-type use (he cuts about 5 cords of firewood per year, and occasionally helps out others with their wood). Mostly hardwoods (Beech, Ash, Maple, Oak), and mostly in the 4" to 10" diameter range (rarely up to 14", maybe more). He's been happy with the 353, and doesn't mind being a bit patient on the rare occasions he gets into the larger stuff. This will be his only saw. He does appreciate a well-made saw, but price is a consideration. He may drool over the 562XP, but he's not likely to spring for it. He a big Husky fan. He might be convinced to step up to a 550, especially if he can find one on sale. (I'm thinking the autotune feature may be a plus... I'm not sure how often he checks carb tuning, or even if he does it on his own or brings it to a dealer.)
Any thoughts?
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The stoichiometric air-fuel ratio of ethanol is half of what gasoline is. 7:1 vrs 14:1
Therefore if you get a slug of gas that has a high alcohol content, your chainsaw is going lean.
I think the 545 would make a good modern day replacement for the 353. The 545 is only 50cc but it runs good with good power.
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Thanks, 660Magnum. I'll recommend he take a close look at the 545.
BTW...Stochiometric ratio of Ethanol is 9:1. It's Methanol that's down below 7:1.
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I've heard of several ways that ethanol might kill saws:
As you described... a slug of gas with higher ethanol content leans out the saw (could just be poorly mixed, or could be phase separation and the ethanol/water mix settled to the bottom of the tank)
Phase separation and the resulting corrosive ethanol/water mix attacking metal parts of the saw.
Ethanol attaches plastic/rubber components of the saw, some of which may allow air leaks, or otherwise lean out the saw through their deterioration.
A saw tuned for non-ethanol fuel, set a bit on the lean side, but not so much that it destroys the saw. Switching to E10 without retuning might lower the stochiometric ratio enough to cause a problem. I'm not sure how likely this is, since switching from "straight" gas to E10 would only change the ratio from 14.6 down to about 14.0. The difference would be even less noticeable if the fuel you started with was some oxygenated fuel other than E10 (MTBE, ETBE, LAME, etc).
Or it could just be that he never had the mixture checked, regardless of the fuel used and it finally caught up with him.
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Just wondering does his 353 have the plastic intake clamp?
I just bought a toasted 353 to rebuild myself, just because no need. I would at least look at rebuilding it anyways even if I bought a new one or at least for learning experience rebuilding. Use used parts or good aftermarket and you can keep the cost down.
545 is a sweet saw and IMO could have replaced the 50cc 346 as well even though it was the 353 replacement.
I have a 545 and 550 on hand right now.
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Just wondering does his 353 have the plastic intake clamp?
I just bought a toasted 353 to rebuild myself, just because no need. I would at least look at rebuilding it anyways even if I bought a new one or at least for learning experience rebuilding. Use used parts or good aftermarket and you can keep the cost down.
545 is a sweet saw and IMO could have replaced the 50cc 346 as well even though it was the 353 replacement.
I have a 545 and 550 on hand right now.
I forgot about the plastic clamp. I had one on my Jonsered 2152. I'll have to check his out.
I know he bought this new more recently than 2007 (when I met him) probably in 2008 or 2009. Unless he got one that had been sitting on someone's shelf for a while, isn't that new enough to have dodged the plastic clamp issue?
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I had assumed the ones with the primer bulb had the metal clamp on the intake?
I have a 2008 350 and it has the metal clamp.
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I had assumed the ones with the primer bulb had the metal clamp on the intake?
I didnt see mention of this 353 having primer bulb, did you? I might have missed it.
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The later 353's had the bigger bore too.
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The later 353's had the bigger bore too.
Tell me more on this subject and comparison of tops pistons etc..
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Where do yo guys get your aftermarket parts for something like this, and who makes decent ones?
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The later 353's had the bigger bore too.
Tell me more on this subject and comparison of tops pistons etc..
I'm getting 350's mixed up with 353's!!!! my problem is that I own a 45mm 350 and do not own a 353.
In the 350's there was the early and late 44mm bore and 45mm bore and I know the 45mm has a dished piston. These are plastic body saws with a clamshell engine. But there is an adapter piece in the clamshell so they use the same cylinder as the 351 or 353. The 345 was a pure clamshell engine piece.
All the 353's are 45mm flat top.
Before the 353 there was the 351 that was 44mm
There needs to be clarification as to which of these cylinders had the removable transfer covers as I know the 350 45mm bore did? I also know that neither of the 346 cylinders had removable transfer covers.
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Where do yo guys get your aftermarket parts for something like this, and who makes decent ones?
There's a significant variation in quality amongst the after market parts. Even one person reporting how good his part is from one company, then you buy the same part from the same company and it has to be massaged before it will work.
I bought a operator presence throttle lever for a Husqvarna 372. It was of a familiar after market brand. I had to sand the width down and then file the latch part where it interfaces with the trigger to get it operating smoothly and not hanging up.
The other day, I was looking at a big bore piston that was in one of my 372's for a short while. Upon close examination, there had been a problem with the bevels on the edges of the ports in the cylinder. Specifically, looking at the piston wear patterns, there was a problem on the cylinder with the shape and bevel along the top of the exhaust port and the vertical sides of the intake transfers towards the exhaust ports. The piston was removed/replaced with a Meteor piston made for a 064 and the cylinder was ported so most of the problem was eliminated?
Meteor brand pistons and Caber rings are well respected after market brands. Yet cut4fun and I were comparing a Meteor piston for a Poulan with the OEM piston and noticing little differences here and there.
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Thanks. The variability in the aftermarket parts has me wondering if he'd be better off going with OEM, especially since this is his first time digging in to a chainsaw.
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There needs to be clarification as to which of these cylinders had the removable transfer covers as I know the 350 45mm bore did? I also know that neither of the 346 cylinders had removable transfer covers.
The 44mm top ends, 351, 2149 and early 350/2150 were a straight open port design, with no removable covers. 353/2152 and later 350/2150 all had the 45mm top ends with the removable covers. As aleready stated, plastic case models had a dished piston and the metal cased saws had the flat top. 346 jugs never had removable covers.
For guys porting, the 45mm jugs offer more potential gains. But staying stock, the 44mm set up responds real good to a muff mod and compression bump by replacing the gasket. It's a strong runner that will surprise ya!
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+1