What's on your bench today?

[bmp01]

2 hours ago, spudulike said:

I think you will find it is the same as the MS200T...pretty sure of that!

Thank you ! 

Ever tried replacing just the O ring ?

Piston groove: Dia = 3.17, Width = 1.20    Bore in carb 5.0 

O ring with ID 3.0, Section 1.1 Viton material would be about right.... probably unobtanium.

 

[Macpherson]

29 minutes ago, bmp01 said:

Thank you ! 

Ever tried replacing just the O ring ?

Piston groove: Dia = 3.17, Width = 1.20    Bore in carb 5.0 

O ring with ID 3.0, Section 1.1 Viton material would be about right.... probably unobtanium.

 

Try SEALS 'R' US, they've got an ebay shop, they pop up first in a search. in my experience o rings are mostly a standard size so a 3 mm ID x 1mm would be the most likely with nearly 0.1mm beyond the 5mm piston.

Apologies for busting in but I've been closely watching this for a solution.

 

 

 

 

[bmp01]

Yeah, I agree regular sizes would be preferable.... the original oring is a little over 1.0mm section I think (hard to be sure it's degraded and changed shape etc). Wouldn't be hard to machine up a new piston to take 1.0mm section Oring but at that stage might as well just buy new from Stihl.

 

[Macpherson]

4 hours ago, bmp01 said:

Yeah, I agree regular sizes would be preferable.... the original oring is a little over 1.0mm section I think (hard to be sure it's degraded and changed shape etc). Wouldn't be hard to machine up a new piston to take 1.0mm section Oring but at that stage might as well just buy new from Stihl.

 

 

What I meant was that if the piston groove is 3.17mm + 2 x 1mm o ring cross section then there would be a 0.17 mm interference fit in the cylinder  with the slight extra width of the groove 0.2 mm or only 0.008" allowing for the slight deformation of the o ring which would seem about right for the push back to form a seal.

 

Sorry for the imperial reference but my brain doesn't work in fractions of mm's😁

 

Here's a link if any use to you, they're usually next day even to me way up here. looks like 5 for 2 quid free delivery👍

 

Metric Viton Rubber O Rings 1mm Cross Section 1.5mm-35mm ID - UK SUPPLIER

WWW.EBAY.CO.UK

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Viton also referred to as FKM has a low compression set and have high temperature and chemical resistance. All of these...

 

[aspenarb]

5 hours ago, bmp01 said:

Yeah, I agree regular sizes would be preferable.... the original oring is a little over 1.0mm section I think (hard to be sure it's degraded and changed shape etc). Wouldn't be hard to machine up a new piston to take 1.0mm section Oring but at that stage might as well just buy new from Stihl.

 

Not really worth the grief of assembling the thing and it not working if the 200t one fits, I measured the bore and spud is right they are the same. I you are struggling to get one I have one here.

 

 

 

 

 

[spudulike]

17 hours ago, bmp01 said:

Thank you ! 

Ever tried replacing just the O ring ?

Yes of course. If the piston isn't scored or through the plating to the brass body, I only replace the O ring. 

I checked, the MS200t ones measure up the same.

[spudulike]

I would avoid using an unknown seal type as I have seen pistons stuck in the bore and have had to drill them out and pull them out with a screw! The piston spring is a low rate and if the piston is too tight, it will get stuck in one position and makes for poor performance off idle!

[Max 201]

So today I decided to dive into my husky 36. It started running very irregular and after a carb swap it still wasn't fixed. (The carb was also in bad shape though) initially I couldn't see any scoring trough the ports but my gut feeling was that something was wrong so I opened it up. I'm fairly new to rebuilding engines but I can't imagine that the sides of a piston are supposed to look like this.

On that note does anyone know husky 136 parts fit the 36? I can't find any differences!

[adw]

The 36/41 were replaced by the 136/141 and replaced by the 137/142, they were all basically the same saw but with improvements as they went on, most parts are interchangeable, the 36/41 had large crank seals housed between the cylinder and base, as the models evolved the seals became part of the bearing housing, so not interchangeable, biggest issue with this model was induction tube splitting, impulse seal splitting, crank seals blowing inside out, muffler coming loose and melting the top cover and in some cases melting through the oil tank.

[spudulike]

Yes...the splitting impulse tube...my favourite!!! I think Husqvarna made it out of Silicone when Nitrile would have done. Use a bit of big fuel line, done it in the past, just got to make sure the length and diameter is bob on perfect.

Make sure you don't clamp the fuel line with the air box divider on reassembly!