Using honing stones on a 242xp chainsaw cylinder?

[kentjames]

Hey everyone

 

Just wondering, having watched videos of it on youtube, if its possible to use honing stones to remove the groves in a cylinder prior to fitting a new piston? Is there enough tolerance within the piston and rings to loose a few thou or would it be useless??

 

Photo attached. Its from the husky 242xp which i am rebuilding after my dad blew it up about 5 years ago, see previous thread.

 

I can source a new cylinder online but wondered if anyone had done it??

 

Cheers, James

[Joe Newton]

No, it's terminally broken. Your best bet is to sell it to me. I'd be doing you a favour, honest!

[adw]

Dont use this type of hone, you need a flex hone, they look like a christmas tree wiith lots of carbon balls on the tips, you will not remove groves in the cylinder, however it will remove any alloy transphered from the piston, the lining on the cyliner is nikasil all you can do is polish it not over size it, the odd pitting in the cylinder is quite good for oil retention, but you want no high spots.

[wrsni]

First you need to figure out what the damage is. If it's aluminium from the piston deposited on top of the plating then you'd be better removing it with wet and dry locally where the deposits are. You can rub as hard as you want to remove the aluminium but you'll not do the plating any harm as it's so hard.

 

If however the damage is into the surface of the barrel then unless it's very shallow the cylinder is for the bin. They can be repaired and replated but I doubt that would be cost effective with a chainsaw.

 

If it's been a straight forward seizure it's most likely to be the first scenario though. Solid stone hones are a specialist tool, even after years of two-stroke engine building I wouldn't even consider trying to use them.

[kentjames]

Joe ... sorry ... she's mine ... eventually when i get round to doing it lol

 

adw - like one of these you mean?

[DCS6800i]

Youve searched for a new cylinder, so are braced to pay out for it. Youve watched youtube videos and have 'learned' how to hone the cylinder. Youve now nothing to lose by giving it a try and seeing what happens - youl either save yourself a cylinder kit and gain some handy experience, or youl knacker an already 'knackered' cylinder (and a new piston) then buy a nice new kit. So give it a go!!

 

Iv been through it, i watched countless videos and bought a cheaper Draper honing kit like the tool in your first post - i never knew you could get the other type!!! Iv now done 2 saws and have new knowledge to bring a dead saw back to life.

 

The spring loaded tool youve got to be very careful with as the stones catch easily in the ports if you bring it too far down the cylinder as you polish up, the other tool will be a far better option.

[spudulike]

The aluminium needs removing with chemical - it etches it off. The remaining oxidised aluminium can be removed by using 150 wet and dry. Do not rub heavily in localised areas as it will produce cavities that will make compression drop and cause blow-by.

 

Once this is done, heavily oil the bore and you can use a two or three legged stone hone but just go lightly and back off the spring adjustment. You wont remove all scores that are a little deep but you never will and it doesn't hurt compression too much from my experience. One did a MS260 and it looked boderline - over 1.5 years on it and very high compression.

 

Just hone to break the surface and allow the new piston to bed in fast.

 

I am not knocking the soft hone - it will work better on open transfers better but the earlier hone you mentioned, will work if used carefully - proof is out there!

[Stubby]

I would try removing any aluminum transfer with acid first ( as spud is always advising ) Might minimize any other work you have to do on the cylinder .

 

 

Oh he is on it before I finished !

Edited February 5, 2015 by Stubby
Spud typed quicker than me !

[adw]

Always used the flex hone with good results, no need for wet n dry/acid or any other chemicals, the flex hone will remove the alloy from the piston and cross hatch the the bore, we have recovered hundreds of cylinders like this.

[wrsni]

Do not rub heavily in localised areas as it will produce cavities that will make compression drop and cause blow-by.

 

Not on a plated cylinder.

 

You can rub it with wet and dry to your fingers hurt and it won't fizz on it.