359 toast piston?

[vapnut257]

Hi, Today I cut a 20" pine, blocked it up, cut the stump. just before my final cut, I stopped my saw. When I tried to restart, It wouldn't. Upon pulling the muffler, the piston looks badly scored. I'm wondering if anyone has any Idea why this may have happened. I was running 50:1 oil mix and had refueled before I startded the job. When done, I had used about 2/3 of a tank. If the saw is toast (this saw has pretty much been a lemon anyway) what am I looking at in rebuilding? I will be doing the work myself. The saw has less than fifty hours on it. I have attached pictures. Any advice would be appreciated.

 

[ericjeeper]

still under warranty?

Or were the 50 hours over a long period?

 

[vapnut257]

Saw is not under warranty. The fifty hours is since 2004, most of the time has been in the last six months. The compression reading was 76 psi.

 

[RiverRat2]

Just prior to the problem did it idle well, ran smooth,

ETC...... no signs of a pressure or vacuum leak????Loose base gasket I would still check for them any way if you are going to rebuild prior to taking it a part any further, if no leaks possibly leaned it out with improper carb adjustment stale fuel or the diaphram may be abit stiff and could not deliver enough fuel under load???

Bummer!!!!! you might get by with a piston kit/ carb kit and hone the cylinder,
but ya gotta figure out why it cooked first??????

 

[Four Paws]

Hi, Today I cut a 20" pine, blocked it up, cut the stump. just before my final cut, I stopped my saw. When I tried to restart, It wouldn't. Any advice would be appreciated.

How dull was your chain? Seems unlikely that the saw would make it through the entire tree with an improperly adjusted carburetor. It also seems unlikely the saw would just melt down without any symptoms first, unless you were forcing it through the cut with dull chain.

Most sing the praises of the 359, odd that you say yours has been a lemon.

 

[Lakeside53]

A dead Husky piston looks just line a dead Stihl...

Could be as simple as a varnished up inlet screen in the carb, or a bad fuel filter.. or bad fuel line...

But.. it didn't happen instantly, so what was it doing in the 10 minutes prior to failure...??

 

[Steve128]

Cost 359 p&c

http://store.baileys-online.com/cgi-bin/baileys/5909?mv_session_id=Cnt3cAyL&product_sku=537 15 73-02

Hope this helps. I agree with RR2 on finding the cause before you begin!

 

[vapnut257]

The bar and chain is new, I keep the chain sharp. It cuts through the wood with very little effort. Before starting my cut, I filled with bar oil, and tank with fuel mixture. (50:1) The mixture is less than thirty days old, high grade fuel. (I didn't shake the can of fuel like I usually do before each refueling) this was my only deviation from protocol, but the tank was about 1/3 full. (mixture separation in the tank also?) The saw started up normally, warmed up, and made all the cuts down to removing the stump flawlessly. I was cutting the stump in half and went most of the way through, leaving only enough to keep my saw off the ground. I turned the saw off with the switch, rolled the stump to make the small finish cut on the other side. At this point the saw would not restart. It didn't run out of fuel. When trying to restart, it just "felt like" something was wrong and thats when I pulled the muffler to look inside. I checked the compression and it was 76 PSI. The cylinder looks clean, but the piston looks toasted to me. (I ain't no saw expert)
I refer to this saw as a lemon because of trouble I have experienced with it before. The air intake clamp on the carb to cylinder was of defective material and replaced under warranty as was the fuel line. (failure). The saw has seen more down time than my lowly Poulan 2100, which has never been in a shop. I like my 359, and when it runs, it's just wonderful and easy to use. If I have to replace the saw I will probably get a 357 or.... god forbid.... a Stihl. (which is most likely the best saw out there). Thanks guys for the comments, I will at least use this saw as a training tool to learn how to replace a cylinder and piston. It will never see the inside of another "saw hostage" dealer shop.

 

[timberwolf]

357 is same lower end and frame except and for the added case stuffers on the crank and the stickers on the side.

There must be a reason, check out the intake for leaks. My 359 came off the shelf on the verge of being lean with the carb tuned as rich as the limiter would allow.

50:1 leaves little safety margine IMHO. Was the muffler opened up?

 

[DGG]

Did you get it new? If you got it from a dealer I'd ask him if he has seen a similar problem. They may have had a lot of improperly made pistons and will still honor the warranty. What brand of 2-cycle oil were you using? Just doens't seem to make any sense that a saw with only 50 hours would suffer this sort of damage.

 

[RiverRat2]

357 is same lower end and frame except and for the added case stuffers on the crank and the stickers on the side.

There must be a reason, check out the intake for leaks. My 359 came off the shelf on the verge of being lean with the carb tuned as rich as the limiter would allow.

50:1 leaves little safety margine IMHO. Was the muffler opened up?

After hearing the rest of the Poop I'm thinkin like T Wolf,,, sounds like it leaned out with some sort of anomoly like an intake leak or something out of the ordinary,,,,,perhaps when the saw gets heated up a bit from normal work load it begins to manifest itself a bit more???? it will b interesting ot see what you find thats why I would do a thorough leak check and dont forget Lakes advice (as always) is very much needed to be investigated,,,, you'd be surprised at the simple trash in a carb inlet screen or mechanical carb problems that are responsible for toasting many saws........

Good luck and keep us posted on your findings,,,,,,

R2'ed

 

[A100HVA]

check the fuel hose for any cracks

 

[Mr.]

The 359 carb is a piece of crap. Can't get around that.

Fred

 

[RiverRat2]

+1

check the fuel hose for any cracks

I think Lake coverd that but good reinforcement!!!

 

[outdoortype]

What's wrong with the 359 carb?

Mr.--If you have any suggestions or things to watch for let us know.

 

[vapnut257]

Iuse only Husqvarna oil and mix according to specs. Fuel line was replaced before under warranty.

 

[RiverRat2]

you still need to pressure test it and the carb

Iuse only Husqvarna oil and mix according to specs. Fuel line was replaced before under warranty.

then test the crankcase for pressure and vacuum, do a search, there are several good threads on leak testers and how to do it!!!!