Muriatic acid treatment on cyl video

[naturelover]

I wrapped and taped some 400 grit sandpaper to a piece of 5/8" hose, stuck that on a drill bit and chucked it in the drill press to sand my 500 cylinder.

My little homemade spindle sander seemed to work pretty well...

 

[H 2 H]

Fantastic thread thanks for posting this even tho its was poted year ago

 

[Philbert]

I ended up with some pits in my 046 cylinder. Were these inevitable, or might I have opened them up with too much acid?

A related question: When do you stop?

- when the acid stops bubbling?

- when all of the vertical lines disappear?

- when you no longer can catch any lines with your fingernail?

Thanks.

Philbert

 

[Philbert]

Can you remove aluminum transfer with a flex hone, like these from Bailey's?

Philbert

Husqvarna Chainsaws, Outdoor Power Equipment and Tree Care Supplies from Bailey's

 

[funky sawman]

thanks for the heating technique roncoinc. I been using muratic acid fur years but never knew about heating the cylinder up first

 

[RTK]

Can you remove aluminum transfer with a flex hone, like these from Bailey's?

Philbert

Husqvarna Chainsaws, Outdoor Power Equipment and Tree Care Supplies from Bailey's

I wouldn't

 

[FixNstuff]

As a side note to this, I always store muriatic acid outside. Even though the container is sealed, the stuff will attack steel anywhere nearby.

I made the mistake of storing some in a metal shed and it ate the paint off the roof over the shelf and rusted a patch before i spotted it. Many of the places that sell it have the container in a heat sealed bag.

I've also discovered that it can be very hard to neutralize. I used it on an old MH bumper to remove rust and even after thorough rinsing and scrubbing with baking soda the bumper continued to rust no matter what paint I put over it. The thing would stain through in a couple of weeks. It was like the muriatic acid started a chemical reaction that I just couldn't stop.

I still use it occasionally but I try to use phosphoric acid first. It's a kinder and gentler acid that's in a lot of autobody rust removers.

 

[RTK]

I ended up with some pits in my 046 cylinder. Were these inevitable, or might I have opened them up with too much acid?

A related question: When do you stop?

- when the acid stops bubbling?

- when all of the vertical lines disappear?

- when you no longer can catch any lines with your fingernail?

Thanks.

Philbert

If it pitted the cylinder the platting was gone in that area. I keep applying and occasionally hit it will a scotch bright pad until I can no longer feel it with my finger nail.


Good point fixnstuff!!

 

[Philbert]

Can you remove aluminum transfer with a flex hone

I wouldn't

If it pitted the cylinder the platting was gone in that area.

I was asking because an 'old school' saw guy told me that that's how he cleaned up cylinders. I was thinking that maybe the acid found a pin-hole pit in the chrome lining of my cylinder, undermined it, and made it into a bigger pit. But the cylinder hone might leave it as a tiny pin-hole, filled flush with aluminum, and still usable?

Philbert

 

[kr5258]

I was thinking that maybe the acid found a pin-hole pit in the chrome lining of my cylinder, undermined it, and made it into a bigger pit. But the cylinder hone might leave it as a tiny pin-hole, filled flush with aluminum, and still usable?

Post up a pic. Depends where the pits are and how big. If the pits are down low, no big deal. If the pits are between the top of the cylinder and the exhaust port then you have to start thinking about longevity.

 

[Philbert]

Post up a pic. Depends where the pits are and how big. If the pits are down low, no big deal. If the pits are between the top of the cylinder and the exhaust port then you have to start thinking about longevity.

Thanks KR,

Once the pits appeared, I got 'experimental' with the cylinder, trying different grits of wet-dry paper, seeing what more acid would do, etc.

This was a first attempt, and I was originally expecting to replace the cylinder, so I am not that disappointed, but think that a more experienced hand might have saved it, so I am trying to learn from it.

The procedure was more tedious than I expected, and I think that 'the next time' I need to be more conservative and sparing with where I place the acid, rather than trying to remove all traces of aluminum and assuming that the plating will protect the rest of the cylinder. That is why I asked the "When do you stop?" question.

I also found it hard to see into the cylinder, especially that area above the exhaust port.

I started with 600 grit wet-dry paper (note: US grits are different than European 'P' grades!) which was very slow. 220 was too rough, and quickly scratched the plating. Even some of my ScotchBrite pads scratched the plating (ScotchBrite comes in different grits - this might have been coarser than the kitchen/dishwashing pads). I think that the 320 to 400 grit wet-dry paper is probably the best compromise to leave you with a lightly honed surface.

I like Naturelover's idea of using a piece of hose as a sanding block, as my fingers got tired fast.

Philbert

 

[RTK]

I was asking because an 'old school' saw guy told me that that's how he cleaned up cylinders. I was thinking that maybe the acid found a pin-hole pit in the chrome lining of my cylinder, undermined it, and made it into a bigger pit. But the cylinder hone might leave it as a tiny pin-hole, filled flush with aluminum, and still usable?

Philbert

If the pin hole is below the top of the ports no biggie, if it is above you might have a problem, I would probably take the chance anyway and run it.

 

[kr5258]

This was a first attempt, and I was originally expecting to replace the cylinder, so I am not that disappointed, but think that a more experienced hand might have saved it, so I am trying to learn from it.

The procedure was more tedious than I expected, and I think that 'the next time' I need to be more conservative and sparing with where I place the acid, rather than trying to remove all traces of aluminum and assuming that the plating will protect the rest of the cylinder. That is why I asked the "When do you stop?" question.

I also found it hard to see into the cylinder, especially that area above the exhaust port.

I started with 600 grit wet-dry paper which was very slow. 220 was too rough, and quickly scratched the plating. Even some of my ScotchBrite pads scratched the plating. I think that the 320 to 400 grit wet-dry paper is probably the best compromise to leave you with a lightly honed surface.

It's better to go slow. Put the swab only where you need to. You can always put more acid on if it didn't dissolve all the transfer deposits.

I find using a small flashlight shining through the intake port really helps to see what you're doing. I also use one of those fancy magnifier lights and a pair of reading glasses. I don't really need the glasses, I just use them when I want to see what I'm doing!

Yep, I use 320 wet/dry myself, cuts fast but still leaves a decent finish.

You can't save them all. I just did a clam shell cylinder and couldn't save it. Man, there is hardly any plating on those things!

As a side note to this, I always store muriatic acid outside. Even though the container is sealed, the stuff will attack steel anywhere nearby.

Agreed!

 

[starsailor]

Just cleaned my first cylinder.

Just cleaned my first cylinder with some "Safer Muriatic Acid" that I picked up at HD. It's a 54mm Mahale piston/cylinder off an 045 AV Electronic I picked up for $25 in a lot of tools from an estate sale. The cylinder had some AL deposits on the exhaust side and the piston had a stuck top ring. The exhaust side piston skirt is a bit worn but still looks usable. I picked up the last set of 54mm rings for it from a local Stihl dealer. I figure I'll try cleaning the deposits off the cylinder, clean the ring grooves on the piston and smooth out the worn skirt a little, slap the new rings in and see what I get.

Well today it took me over an hour with a dozen or so Q-tips with this acid to get the deposits off the cylinder wall. I think "Safer Muriatic Acid" means a weaker concentration of hydrochloric. It seemed to go well, albeit very slowly. I got all of what I think are the AL deposits except for 2 very small scratches that I can't feel with my finger nail but I can just feel with my finger tip. I cleaned up a slight gray discoloration of the treated area with a very light sand with some 1000 grit wet/dry sand paper. The Nikasil now looks the same as the rest of the cylinder with no pits or worn spots.

Anyway my question is this. While scrubbing with the acid the Qtips all turned a dark green color. I switched to a clean Qtip each time this happened. Does anyone know what makes it turn green? Is the aluminum, the Nikasil, or something else? I know muriatic and copper will make green, but I just don't know what's going on here.

 

[cheeves]

Why thank you Lee..
worth a 116 ??
i can even pick it up ??

be there in two hrs ??

120Si !! :msp_biggrin:

 

[SkippyKtm]

Just cleaned my first cylinder with some "Safer Muriatic Acid" that I picked up at HD. It's a 54mm Mahale piston/cylinder off an 045 AV Electronic I picked up for $25 in a lot of tools from an estate sale. The cylinder had some AL deposits on the exhaust side and the piston had a stuck top ring. The exhaust side piston skirt is a bit worn but still looks usable. I picked up the last set of 54mm rings for it from a local Stihl dealer. I figure I'll try cleaning the deposits off the cylinder, clean the ring grooves on the piston and smooth out the worn skirt a little, slap the new rings in and see what I get.

Well today it took me over an hour with a dozen or so Q-tips with this acid to get the deposits off the cylinder wall. I think "Safer Muriatic Acid" means a weaker concentration of hydrochloric. It seemed to go well, albeit very slowly. I got all of what I think are the AL deposits except for 2 very small scratches that I can't feel with my finger nail but I can just feel with my finger tip. I cleaned up a slight gray discoloration of the treated area with a very light sand with some 1000 grit wet/dry sand paper. The Nikasil now looks the same as the rest of the cylinder with no pits or worn spots.

Anyway my question is this. While scrubbing with the acid the Qtips all turned a dark green color. I switched to a clean Qtip each time this happened. Does anyone know what makes it turn green? Is the aluminum, the Nikasil, or something else? I know muriatic and copper will make green, but I just don't know what's going on here.

I wouldn't reuse that piston, but I'll leave that up to you...:msp_wink:

I was wondering what that "safer" stuff was, I saw it at HD but I went to my little mom and pop hardware store to get the real stuff, and I'm glad I did. :msp_smile:

You must have a chrome cylinder there, because that's what color I get whenever I clean up a chromed cylinder. With Nikasil you don't get the color change.

 

[Agrarian]

In an earlier reply, someone said not to use a hone on a cylinder. I'm curious if this is true for a Flex-Hone (ball hone) this since the manufacturer of the flex hone has a special line using aluminum oxide as the material that they claim is explicitly for doing Nikasil plated cylinders. Since Nikasil (Nickel / Silicon Carbide) is harder than aluminum oxide, shouldn't this be ok to use?

I realize these hones are not for removing the aluminum transfer from the piston - the acid is best for that IMHO. But the hone will knock down any high points from the piston-caused damage - won't it? And unlike using hand applied sandpaper, the flex hone would use even pressure so that there was no localized cylinder distortion. Am I off-base with this thinking?

 

[starsailor]

I wouldn't reuse that piston, but I'll leave that up to you...:msp_wink:

I was wondering what that "safer" stuff was, I saw it at HD but I went to my little mom and pop hardware store to get the real stuff, and I'm glad I did. :msp_smile:

You must have a chrome cylinder there, because that's what color I get whenever I clean up a chromed cylinder. With Nikasil you don't get the color change.

Thanks skippy!

I hear you on the piston, but I have so little into it at this point that can't see spending alot of time trying to find a "quality" replacement 54mm piston for this cylinder. There are so many crap aftermarket pistons out there that are probably worse than what I've got.

I guess I should really base this decision off of some real data. What measurements would you use? Dia. at the bottom of the skirt? Dia. at the top of the piston?

Also, both the piston and cylinder are labeled Mahale. I thought all Mahale cylinders were Nikasil. Can you tell chrome or Nikasil from the numbers on the cylinder?

 

[Alex D]

thanks for the enlightenment brother, any thoughts on the strength of my acid?

Id personally use hardware strenght only and heat the cylinder up. I tried making it more concentrated by putting it in a glass container on top of a hot plate and boiling it outside- gave off white fumes turned it off when they stopped- got it up pretty damn close to 100% id guess completly destroyed a cylinder i still have it somewhere i think ill post a pic up.

 

[RTK]

In an earlier reply, someone said not to use a hone on a cylinder. I'm curious if this is true for a Flex-Hone (ball hone) this since the manufacturer of the flex hone has a special line using aluminum oxide as the material that they claim is explicitly for doing Nikasil plated cylinders. Since Nikasil (Nickel / Silicon Carbide) is harder than aluminum oxide, shouldn't this be ok to use?

I realize these hones are not for removing the aluminum transfer from the piston - the acid is best for that IMHO. But the hone will knock down any high points from the piston-caused damage - won't it? And unlike using hand applied sandpaper, the flex hone would use even pressure so that there was no localized cylinder distortion. Am I off-base with this thinking?

No need to ever use a hone, some will disagree. Clean deposits off with acid and if you like run a scotch brite pad with kerosene or similar.