2 Stroke chainsaw maintenance - husqy 50 and 55

[TommyTreeTime]

I know some of this is chainsaw and brand specific but is there a better than average video tutorial out there to get them running really nice? Or will i just have to go to the old google and give it a whirl? I'm a mechanical engineer in the past but admittedly have had limited exposure to small engines and their maintenance. Got all three saws sharp and cutting good once they're running. Nice big shavings.

But both my Husqy rancher 50 and 55 start hard & the 50 doesn't want to idle. 72 tooth on both. I find myself having to give a little throttle once I hear one want to start. Without that throttle they barely want to start.

Premium gas (up to 10% ethanol), no additives others than the proper oil mixed in. Admittedly i used some mixed last season. Is that enough of a no no to foul things up?

I've spent more time dinking around with saws on site and pulling that cutting by far.

 

[Cool Breeze]

I'm relatively new to chain saws but have a Husqvarna 525 LS (commercial grade string trimmer). It did not like ethanol gas and I think I put the high octane in it. It had trouble starting and it just felt under powered. Once I used that up, I stuck to ethanol free gas, stabilizer, and Husqvarna 2 stroke oil mix. I've left that gas in the trimmer for months and over the winter and have not had any of the above mentioned problems.

Im not sure if stabilizer helps ethanol gas to NOT attract water. It may help keep the gas able to ignite... But the videos (if you trust them), seem to indicate that ethanol attracts water no matter what. I could be wrong but moral of story was ethanol free gas was the way.

 

[Exophysical]

Hard starting is often a result of the fuel line draining back to the tank. I'd install a new fuel filter, fuel line, and carb kit. Goes without saying, give the carb a good cleaning while your at it. Too, check the intake gasket and boot for leaks on both of them by spraying fuel, carb cleaner, or brakeclean into those areas while the saw is running. If theres a leak you should hear the saw RPM drop when the extra fuel gets sucked in.

 

[irhunter]

I would say, the very first step is to adjust the carbs to factory spec, make sure the air filters are clean, and the spark arrestors are not gunked up.

Then, report back.

If running gas with any alcohol in it...I contend, 3 months is "considerably too old."

Roy

 

[TommyTreeTime]

I would say, the very first step is to adjust the carbs to factory spec, make sure the air filters are clean, and the spark arrestors are not gunked up.

Then, report back.

If running gas with any alcohol in it...I contend, 3 months is "considerably too old."

Roy

Picked up ethanol free gas this weekend for starters. A little behind over here, thanks for more good advice.

 

[irhunter]

Picked up ethanol free gas this weekend for starters.

Cool.

I think E10 gas is fine as long as it is crazy-fresh. Like, use it "this week."

I will also say, keep at those saws. They are really fine saws.

Do you have the shop manual?

Roy

 

[Chevboy0167]

https://www.mymowerparts.com/pdf/Husqvarna-Service-Repair-Manuals/W9200002.pdf

 

[TommyTreeTime]

Cool.

I think E10 gas is fine as long as it is crazy-fresh. Like, use it "this week."

I will also say, keep at those saws. They are really fine saws.

Do you have the shop manual?

Roy

Now I do!

Thanks Chevy!

 

[TommyTreeTime]

Cool.

I think E10 gas is fine as long as it is crazy-fresh. Like, use it "this week."

I will also say, keep at those saws. They are really fine saws.

Do you have the shop manual?

Roy

So i went to work on them last night, replace anti-vibe + chain catcher on both. One was actually missing one, most were beat. neither had oem catcher which retains one of the anti-vibe bushings.

Thought that and gas was only thing wrong with 55 and I got her started, even idling pretty well. Went to do a test cut and it's very odd...

It will either grab and throw noodles or it won't cut at all with the weight of the saw. It's like maybe the bar is bent or maybe my rakers? IDK. It just floats on top of the wood or with a little pressure and pivoting the saw around it's longest axis suddenly it will start ripping through and get stuck up again depending on the angle it's held around the long axis.

I'm use to my older 50 just cutting itself straight with it's own weight pretty much?

The bar on the 55 is a bit more beat, has some signs of getting really hot (blue) and actually has a rolled burr on the top and bottom edges. Excuse me if that is normal but i have not gotten into educating myself on the bars yet at all. Both bars are pretty beat. Both look original I'd have to say...

NOW back to the 50... was seized up! Probably from running so poorly last time i used it.

Thought it might be hydro locked, NOPE, pulled plug and it still wouldn't budge. Put a little bit of the new gas in the 50 and played with the "flywheel?" it eventually worked free slowly and eventually moved really smooth. Too smooth, it feels like really weak compression now?

I see kits cost like nothing on amazon to rebuild top end? Maybe just do it for education purposes? Better to by a name brand or performance option some where for a little more money?

Sorry, a lot to un pack here but these saws were run hard and abused, so there is a lot of variables coming up each time i dig into the original problem of the day.

 

[TommyTreeTime]

I would say, the very first step is to adjust the carbs to factory spec, make sure the air filters are clean, and the spark arrestors are not gunked up.

Then, report back.

If running gas with any alcohol in it...I contend, 3 months is "considerably too old."

Roy

Gonna check the Spark arrestors and air filters tonight while i'm working on trouble shooting this other stuff i mentioned above.

 

[Sidecarflip]

Why is it that posters always butcher the Husqvarna name? If you cannot spell it out correctly or are too lazy to, Just shorten it the 'Husky', not something butchered becauese you lack the knowledge.

Why I don't respond to threads like this one...

 

[irhunter]

Why is it that posters always butcher the Husqvarna name? If you cannot spell it out correctly or are too lazy to, Just shorten it the 'Husky', not something butchered becauese you lack the knowledge.

Why I don't respond to threads like this one...

So, let me get this right...

You are yanked up over "Husqy" versus "Husky."

Right?

And, your "becauese" is fine?

Roy

 

[Sidecarflip]

So, let me get this right...

You are yanked up over "Husqy" versus "Husky."

Right?

And, your "becauese" is fine?

Roy

In reality, I don't give a hoot but I do have a very vintage and collectable 'Husky' built 308 rifle they manufactured for Smith & Wesson in the early 60's in pristine condition so I do know the correct spelling of their name.

Like oil threads. I find them entertaining but seldom post any comment. At my age, 73, I don't get 'yanked up' over anything, whatever in the hell that means, I haven't a clue.

 

[ihookem]

To the O.P. I think you wrote you had old gas in it from last year. If so that is the problem . I had soem old gas in my ouboard that was about 7 month old and it ran terrible. I didnt even remove the old gas, just added some new and it ram way better.

 

[Exophysical]

In reality, I don't give a hoot but I do have a very vintage and collectable 'Husky' built 308 rifle they manufactured for Smith & Wesson in the early 60's in pristine condition so I do know the correct spelling of their name.

Like oil threads. I find them entertaining but seldom post any comment. At my age, 73, I don't get 'yanked up' over anything, whatever in the hell that means, I haven't a clue.

Here in Canada those rifles are not really collectable... but they are sure awesome hunting rifles. Every bit the quality of a pre-64 Winchester for 1/3 the price. Being mainly a stillhunter/ tracker I like the "Lightweight Carbine" version 1600's. I've got two, one .270 and the other a 30-06, both with set up with identical trigger jobs and 2-7x scopes. A couple times since I started using them my wife volentarily gave me the go-ahead to "spend whatever, just get what you want".... and after several rounds of extensively shopping around I'm still using the Huskays. That should speak volumes right there.

 

[Exophysical]

So i went to work on them last night, replace anti-vibe + chain catcher on both. One was actually missing one, most were beat. neither had oem catcher which retains one of the anti-vibe bushings.

Thought that and gas was only thing wrong with 55 and I got her started, even idling pretty well. Went to do a test cut and it's very odd...

It will either grab and throw noodles or it won't cut at all with the weight of the saw. It's like maybe the bar is bent or maybe my rakers? IDK. It just floats on top of the wood or with a little pressure and pivoting the saw around it's longest axis suddenly it will start ripping through and get stuck up again depending on the angle it's held around the long axis.

I'm use to my older 50 just cutting itself straight with it's own weight pretty much?

The bar on the 55 is a bit more beat, has some signs of getting really hot (blue) and actually has a rolled burr on the top and bottom edges. Excuse me if that is normal but i have not gotten into educating myself on the bars yet at all. Both bars are pretty beat. Both look original I'd have to say...

NOW back to the 50... was seized up! Probably from running so poorly last time i used it.

Thought it might be hydro locked, NOPE, pulled plug and it still wouldn't budge. Put a little bit of the new gas in the 50 and played with the "flywheel?" it eventually worked free slowly and eventually moved really smooth. Too smooth, it feels like really weak compression now?

I see kits cost like nothing on amazon to rebuild top end? Maybe just do it for education purposes? Better to by a name brand or performance option some where for a little more money?

Sorry, a lot to un pack here but these saws were run hard and abused, so there is a lot of variables coming up each time i dig into the original problem of the day.

Check for air leaks on that 55, make sure the carb is working properly and set up right then try a new chain. The 55 I have feels pretty strong when its reving in its happy place, but bog it down and it will fall on its face pretty suddenly. If I had to hazard a guess I'd say the the 55's powerband, coupled with a dodgy chain and the high jet being poorly adjusted could cause the problem you are describing.

The one thing you need to ask however; assuming the carb was properly adjusted at some point, why would it be working poorly now? Your carb could be crudded up, you could have an air leak etc. If you simply tune out the symptoms without looking for/ dealing with the root cause it could end up cooked like your 50.

The 55 is a pretty comon saw, if you look around you should be able to find a usable OEM takeoff cylinder in good shape. Thats what I would put on the 50.

 

[Chevboy0167]

I have seen where the intake tube and impulse seal tube rub against each other. Causes a hole or split in the impulse tube that creates an air leak and weak impulse vacuum to run the fuel pump circuit in the carb.... equals starving for fuel and running lean.

This can cook the top end and starve all the crank bearings of fuel/oil mix.

 

[coffeebrk]

But both my Husqy rancher 50 and 55 start hard & the 50 doesn't want to idle.

It would be great if you could do one saw at a time.
What do the pistons and cylinders look like?
Have the carbs been gone through?
New kits in the carbs?
OEM carbs?
Have you determined that the fuel line from the tank to the carb is good by putting 10 lbs of pressure into fuel line at fuel tank?
These saws should start easily and idle perfectly.

 

[muddy42]

I have seen where the intake tube and impulse seal tube rub against each other. Causes a hole or split in the impulse tube that creates an air leak and weak impulse vacuum to run the fuel pump circuit in the carb.... equals starving for fuel and running lean.

This can cook the top end and starve all the crank bearings of fuel/oil mix.

View attachment 1185392 View attachment 1185395

Agree with this. To be honest the way the impulse enters the cylinder isn't the best design (also the choke isnt great but that's a seperate matter). Pressure and vac test it, making sure this impulse and boot is included in the test, in other words sealing behind the carb.

 

[Exophysical]

Gonna check the Spark arrestors and air filters tonight while i'm working on trouble shooting this other stuff i mentioned above.

So, I put an aftermarket top end kit undetermined lineage ( got it in a lot of parts I purchased) in my 55, just for the hell of it, and also rebuilt the carb... afterwards I was having the problem you described. Saw either reving or dying in the cut, turned out that on the bottom of the carb I had put the gasket on the wrong side of the diapham, the main point being that it was a fuel delivery problem.

Coupled with the hard starting that was your original probem, I think you definately need to go through the things I reccomended in my first post before you run that saw any more.