Can this cylinder be used?

[gmax]

This piston and cylinder is from a Olympk 284 F, I cleaned up the cylinder using
600 grit wet paper & WD 40, I can slightly feel where its scored.
Is it worth using again? , I'm having trouble finding another cylinder for it, the
rest of the chainsaw is good.

 

[blsnelling]

Pictures always tend to make things look worse than they are. I bet a new piston and rings would make great compression in that cylinder. Go for it!

 

[gmax]

Pictures always tend to make things look worse than they are. I bet a new piston and rings would make great compression in that cylinder. Go for it!

Good, thanks, I bought a used piston & cylinder from a US ebay shop, but the cylinder is different (nowhere to mount the coil on the cylinder), but I might
be able to use the piston ( the gap between the piston skirt is slightly smaller).

Or I could just send the lot back & look for a piston elsewhere, that's the problem with these old Olympk saws, well made but parts are hard to locate'
cheers

 

[Bowtie]

Have you tried a little muriatic acid applied with a q-tip? It looks like most of that is aluminum transfer. It might clean up a lot better if you try that. Lots of info here about that process.

 

[gmax]

not yet, is that the same as Hydrochloric Acid that goes in car batteries?

 

[Dan Forsh]

Yep same stuff

 

[blsnelling]

That doesn' really look to me like transfer. Just looks like the scratches you get as the result of a seizure. Was there transfer on there that you already sanded off?

 

[Bowtie]

not yet, is that the same as Hydrochloric Acid that goes in car batteries?

Its a different acid, but Im not sure if it would work the same or not. It may be too caustic, but I have never used it on a cylinder. Muriatic acid is available at most any hardware store. The thing is to make SURE you dont get it on the aluminum part of the cylinder. It raises hell with aluminum. Thats how it cleans the aluminum transfer off of the cylinder wall. I apply it to the the aluminum with a qtip, wait maybe a minute, then sand with 400-600 grit sandpaper. Wash, and try again. It will take several applications, but have patience, and it works very well.

 

[Dan Forsh]

Muriatic acid is the same as Hydrochloric acid. Muriatic is the old name for it. Check your bottle it should show HCI on the label.

 

[gmax]

That doesn' really look to me like transfer. Just looks like the scratches you get as the result of a seizure. Was there transfer on there that you already sanded off?

Yes I sanded some of the transfer off, there was no seizure, the motor would still turn over with some compression but not enough to start

 

[Bowtie]

Muriatic acid is the same as Hydrochloric acid. Muriatic is the old name for it. Check your bottle it should show HCI on the label.

Wow, good info Dan, I didnt know that.

 

[gmax]

Its a different acid, but Im not sure if it would work the same or not. It may be too caustic, but I have never used it on a cylinder. Muriatic acid is available at most any hardware store. The thing is to make SURE you dont get it on the aluminum part of the cylinder. It raises hell with aluminum. Thats how it cleans the aluminum transfer off of the cylinder wall. I apply it to the the aluminum with a qtip, wait maybe a minute, then sand with 400-600 grit sandpaper. Wash, and try again. It will take several applications, but have patience, and it works very well.

Ok I'll give it a go, any reason I couldn't just take a little from my car battery?

 

[yo2001]

I don't know if anyone do this but a steel wool on the end of drill bit chucked on a cordless drill works pretty good on cleaning fine detail stuff.

 

[Dan Forsh]

Ok I'll give it a go, any reason I couldn't just take a little from my car battery?

I wouldn't know what the concentration would be from your battery, but I can't see any harm in trying it with care.

 

[gmax]

I wouldn't know what the concentration would be from your battery, but I can't see any harm in trying it with care.

Great, that will save me a trip to the hardware shop.

 

[Jacob J.]

There's probably a piston from a different application that would work in that cylinder. You can send me a PM with the measurements on diameter, wrist pin, and crown height and I'll help you find a new one.

 

[Mad Professor]

Battery acid is sulfuric acid, diluted to something like 33% by weight. It should oxidize aluminum like hydrochloric acid. It is the hydrogen ions being reduced so that is the difference in reduction potentials you are concerned with; metals vs hydrogen. The concentration (normality) of the acid also plays a role.

Other acids will chew up things by oxidation/reduction in different ways, i.e. oxidizing acids like nitric acid.

 

[gmax]

Battery acid is sulfuric acid, diluted to something like 33% by weight. It should oxidize aluminum like hydrochloric acid. It is the hydrogen ions being reduced so that is the difference in reduction potentials you are concerned with; metals vs hydrogen. The concentration (normality) of the acid also plays a role.

Other acids will chew up things by oxidation/reduction in different ways, i.e. oxidizing acids like nitric acid.

Cool! I guess that's why your the "Mad Professor"

 

[litefoot]

Ok I'll give it a go, any reason I couldn't just take a little from my car battery?

I wouldn't think so, the electrolyte in your car battery is mostly water (2/3 water and 1/3 sulfuric acid).

Edit to add: The professor typed faster than me. And here I was thinking he was off with Ginger somewhere.

 

[gmax]

There's probably a piston from a different application that would work in that cylinder. You can send me a PM with the measurements on diameter, wrist pin, and crown height and I'll help you find a new one.

Jacob, I presume this is the crown height in the photo 20mm, the other photo is of the piston that came with the cylinder, it's almost the same apart from the
gap at the bottom of the piston skirt is smaller ( I'm not sure if that will be a problem).
If the seller wont refund the piston & cylinder I might have to try use the piston, anyway I'll send you a pm , cheers