Husqvarna 50/51/55 repair thread.

[malk315]

Thanks Eric, great thread, I had read it back when you first posted but had forgotten all about it. I guess that makes this thread a little redundant.

Redundancy is good! Helps to learn all possible tricks when working with these saws. The 50/51/55 chassis is a cool setup.

Sent from my XT1585 using Tapatalk

 

[rattler]

Great thread Joe thanks

 

[PogoInTheWoods]

Had time to read the other thread. Good one there, too.

It's pretty well known that stock squish on these is in the .060 range..., but they still pull in the neighborhood of 160psi give or take due to a very compact combustion chamber. Even so, I still check squish when using any aftermarket top end that isn't a Meteor just to be safe. Dirko is my sealant of choice and I've never had a problem with it.

And here's is quick vac/pressure test approach using Gorilla Tape for checking the seals and intake bulkhead before putting everything back together. Works great on clean surfaces. Do vac first to seal it a little better than just pressing it on. Then it'll hold 6~7 lbs. of pressure no problem (if the surfaces were clean when the tape went on). Obviously a redneck leak check, but it's fast and if everything is tight you're good to go. If there's a leak you can trouble shoot it up to a point using pressure and soapy water before needing to go with block-offs for smaller leaks needing more pressure to isolate.

Anyway, I've taken some raggin' for the Gorilla Tape, but it works. Will get ya another 100 miles out of a pair o' cheap Nikes too!

​

 

[PogoInTheWoods]

Another tip if you haven't discovered it (or something better) already...

When that little square retainer on the bar adjuster disintegrates and the adjuster bolt keeps backing out, just use a snip of fuel line instead. Butt simple and works great on any saw that uses the retainer piece. I just happened to try it first on a 55.

​

 

[Onan18]

@afleetcommand and @Spike60 did a "Saw College" on this chassis, tons of great info in this video.

 

[Stump Shot]

The air filter on a 50 is also the choke. It just pushes against the air horn when the lever is pushed on the cover.
This one had the retaining tabs broken by its owner so it didn't stay on, sucked some dust through. Sometimes the little details matter.

 

[PogoInTheWoods]

Pretty nice 300th. I just sold one nearly as nice. Wish I would have kept it now.

And I do I like those ultra-fine screen filters. Think I'd be fixing that one somehow (if you haven't already).

 

[Stump Shot]

Pretty nice 300th. I just sold one nearly as nice. Wish I would have kept it now.

And I do I like those ultra-fine screen filters. Think I'd be fixing that one somehow (if you haven't already).

Would be nice to have a sticker for the starter cover, but they're like De Soto's now.

 

[Stump Shot]

I found one on eBay for mineView attachment 96346

Nice!

 

[PogoInTheWoods]

Yep. That's a sweet one.

Back to Spike's video for a second...

He mentioned something really important toward the end that was just sorta casually tossed in regarding the screw-on air filters
AND THAT DAMNED NUT just slid into the filter base. If you're taking one of those types apart for the first time and disassembling the entire intake setup there is a high probability that the damned nut will fall out somewhere along the line. You'll either lose it and not even know it until you try to tighten the air filter screw again sayin' "whuh?", or find it laying somewhere wonderin' where the hell it came from until you try to tighten the air filter screw again and realize, "Ah Ha!" Trust me, I've scratched my head over that one a coupla times.

 

[Dub11]

Yep. That's a sweet one.

Back to Spike's video for a second...

He mentioned something really important toward the end that was just sorta casually tossed in regarding the screw-on air filters
AND THAT DAMNED NUT just slid into the filter base. If you're taking one of those types apart for the first time and disassembling the entire intake setup there is a high probability that the damned nut will fall out somewhere along the line. You'll either lose it and not even know it until you try to tighten the air filter screw again sayin' "whuh?", or find it laying somewhere wonderin' where the hell it came from until you try to tighten the air filter screw again and realize, "Ah Ha!" Trust me, I've scratched my head over that one a coupla times.

Is there a fix?

 

[Stump Shot]

Thanks,I like these saws,There not the fastest 50 cc saws but I like the feel of them just enjoyable to use.

I hear you, I find myself reaching for this one more and more. Since it broke in it really runs great and is a treat to cut with. Spools up quick and is hell on limbs. Open ports are still ports. Lol

 

[afleetcommand]

How about the ugliest 51 you every saw..but could still be brought back to life?
Part 1

Part 2

 

[Stump Shot]

Changing out the seals, worm gear in the way. Let's find a way to get it out of there right quick and easy. There's the Husqvarna way and all the 5,000 other ways people have come up with. If it works for you, it's the right way. This is just my way, and if it helps or inspires someone to help find their way, then it's all good.



A half to three quarter pipe adapter is screwed on the gear threads.


Here's where I deviate, instead of finding a bolt, I just use a clamshell puller.


Comes right off and the worm gear can be threaded out with just your finger.


To reinstall after the seal is put in, heat up the worm gear and just drop it on the shaft.

 

[Stump Shot]

Used the FIT puller to get the seals out. Pretty easy...



I really like the Husqvarna tool for putting the seal on the PTO side.
While they don't show one for it, the 272 series does the job. 502 50 53-01


Important note: Seal on the flywheel side should be 1 mm proud, PTO side 1 mm sunk under flush.

 

[decableguy2000]

try 505 38 17-23 for the seal protector sleeve

 

[PogoInTheWoods]

I'm sure there've been some revisions since I ran across this version but it's fairly inclusive for the older saws.

 

[huskihl]

Had time to read the other thread. Good one there, too.

It's pretty well known that stock squish on these is in the .060 range..., but they still pull in the neighborhood of 160psi give or take due to a very compact combustion chamber. Even so, I still check squish when using any aftermarket top end that isn't a Meteor just to be safe. Dirko is my sealant of choice and I've never had a problem with it.

And here's is quick vac/pressure test approach using Gorilla Tape for checking the seals and intake bulkhead before putting everything back together. Works great on clean surfaces. Do vac first to seal it a little better than just pressing it on. Then it'll hold 6~7 lbs. of pressure no problem (if the surfaces were clean when the tape went on). Obviously a redneck leak check, but it's fast and if everything is tight you're good to go. If there's a leak you can trouble shoot it up to a point using pressure and soapy water before needing to go with block-offs for smaller leaks needing more pressure to isolate.

Anyway, I've taken some raggin' for the Gorilla Tape, but it works. Will get ya another 100 miles out of a pair o' cheap Nikes too!

View attachment 96110

View attachment 96111

View attachment 96112​

I'd never hack on anyone for using Gorilla tape as a block off. Grab a piece, poke a couple holes in it, or put the intake clamp over it, and go. If the exhaust port surface is clean, you almost don't need to install the muffler over it to do just a vacuum test. That stuff works great

 

[Tor R]

Used the FIT puller to get the seals out. Pretty easy...
View attachment 97846
View attachment 97848

I really like the Husqvarna tool for putting the seal on the PTO side.
While they don't show one for it, the 272 series does the job. 502 50 53-01
View attachment 97850

Important note: Seal on the flywheel side should be 1 mm proud, PTO side 1 mm sunk under flush.

Steve, lathe out a seal adapter system, special on models you often swap seals on.
The one I plan to use as a base is the seal mandrel to 550, #575 34 70 01

try 505 38 17-23 for the seal protector sleeve

I can recommend them seal protector sleeves, I don't have the 55 sleeve (not yet), but I've used the sleeves for 242 and 346&550, they are worth every dolar.


Question for your 55 guys (for some odd reasons I've never got any 50,51,55 projects from my dealer).... There is two different crank mounting kits from Husky who both are ment for this serie.
502 50 30 09, 50>9250856, 45>9251168, 40>9101116
502 50 30 12, on them newer ones.

Anyones knows if there was different crank threads on them 40/45/50's through their life span?

 

[RIDE-RED 350r]

Another good thread @Onan18

I have a 55 open port mostly torn apart. The P&C is smoked and it needs several other bits and pieces and some TLC. Once my 242 is done I'll probably dig into that one. I'm thinking I might try the Huztl 55 Closed Port P&C kit on this one. I don't really NEED another saw in this size as I have a solid 359 and a ported 357, but the chase to make something out of nothing is where the fun lies.

Good tips on the oil pump worm gear removal @Stump Shot . Do all 51 and 55 have this setup?

I can see why these saws remain popular. All of the benefit of "professional class saw" construction but at a lower price point and a bit less performance compared to the XP counterpart of it's day. Not unlike how the 359 related to the 357xp and the triple-nickel relates to the 562xp now.