346xp OE Peek @ piston. Look OK?

[bwalker]

Correct me if i am just babbling, BUT after you use the scotch brite do a thorough cleaning. Forgot you already have it back together.. Next reader may benefit.

This is just me, but using scotch bright on aluminum hurts more than it helps.

 

[ChillyB]

This is just me, but using switch bright on aluminum hurts more than it helps.

I worked for a long time in an engine plant where chainsaws would easily fit inside one engine cylinder. Scotch Brite was banned from coming onto company property.

 

[Vintage Engine Repairs]

fine grit (600) Scotch brite on crown to remove carbon by hand is perfectly fine. It doesn’t even mark it let alone remove any ally. Yes wash it well after

 

[BrettS]

What would be a good carbon removal chemical that doesn't harm aluminium (or ah loo ma nim)?.

 

[Chevboy0167]

A few spray can styles. Some a bit pricey....

https://www.crcindustries.com/products/marine-engine-tune-up-decarbonizer-13-wt-oz-06121.html
https://www.ebay.com/itm/274930125514?epid=773031759&hash=item40031ccaca:g:0IcAAOSwbfNhL92o
https://www.ebay.com/itm/194881690183?epid=28020713649&hash=item2d5fda9a47:g:fFkAAOSwK5hiHbsH

 

[Chevboy0167]

Cheap route would be throttle body cleaner and some manual labor. Old toothbrush and some towel scrubbing time! May help to soak all parts in a container of gas or parts dip for a week to help loosen up the hard stuff.

https://www.walmart.com/ip/GUNK-CC3...p.ds&msclkid=4e21e22e277219e9e42d807562c69de3
https://gunk.com/product/gunk-parts-cleaner-with-drip-basket-cc3k/

 

[BrettS]

Cheap route would be throttle body cleaner and some manual labor. Old toothbrush and some towel scrubbing time! May help to soak all parts in a container of gas or parts dip for a week to help loosen up the hard stuff.

https://www.walmart.com/ip/GUNK-CC3...p.ds&msclkid=4e21e22e277219e9e42d807562c69de3
https://gunk.com/product/gunk-parts-cleaner-with-drip-basket-cc3k/

Don't think you can get "GUNK" here in New Zealand.

 

[Chevboy0167]

Check your auto parts stores and ask them what they can get that is similar in your area.

 

[BrettS]

Check your auto parts stores and ask them what they can get that is similar in your area.

I have, their reply was that they don't carry bulk cleaning products (the product I wanted) as it's flammable, implying that I can buy multiple aerosol cans of the same stuff they did stock instead.

 

[Chevboy0167]

I would think the auto stores would something like this...

https://www.crc.co.nz/ThrotLBody/6895-2369d770-7bb2-4e15-988f-51df13b4961a/
https://www.crc.co.nz/GDI-Intake-Valve--Turbo-Cleaner/6895-84547a2b-5cf3-49b8-8806-5b83d967f8c7/

 

[BrettS]

I would think the auto stores would something like this...

https://www.crc.co.nz/ThrotLBody/6895-2369d770-7bb2-4e15-988f-51df13b4961a/
https://www.crc.co.nz/GDI-Intake-Valve--Turbo-Cleaner/6895-84547a2b-5cf3-49b8-8806-5b83d967f8c7/

I usually use CRC brake cleaner for carbs etc, bit tough on the pocket buying it in 600gm spray tins all the time though. I see CRC make "EXOFF", wondering if that is any good.

 

[huskihl]

I’ve scotchbrited probably 500 chainsaw cylinders. I run a scotchbrite mandrel sized a little bigger than the bore after I’m done porting every cylinder and then flush it all out with mineral spirits in the parts washer. For carboned up pistons I use scotchbrite rolloc discs along with some penetrating oil to remove it from the crown and mandrels to clean it off the skirts. But everything is flushed out well in the parts washer afterwards

 

[Engineeringnerd]

Piston looks fantastic, machine marks are still there.

Gently clean off the carbon with some fine scotch brite and treat it to a new ring.

scotchbrite the cylinder walls too.

pop the c-clips out and inspect the small end bearing, replace it if you’re unsure.

New c clips, clean the gudgeon pin and finish off with a pressure and vac test. New carb kit, lines and filter and it will last another 20 years.

Thanks Vintage. At some point I'm going to put a big bore in there, but it looks like what's there has a few more years in it to give!

 

[Engineeringnerd]

I’ve scotchbrited probably 500 chainsaw cylinders. I run a scotchbrite mandrel sized a little bigger than the bore after I’m done porting every cylinder and then flush it all out with mineral spirits in the parts washer. For carboned up pistons I use scotchbrite rolloc discs along with some penetrating oil to remove it from the crown and mandrels to clean it off the skirts. But everything is flushed out well in the parts washer afterwards

Would be nice to see what that Scotchbrite/Mandrel setup looks like. Perhaps take a picture when you do cylinder #501?

 

[huskihl]

Would be nice to see what that Scotchbrite/Mandrel setup looks like. Perhaps take a picture when you do cylinder #501?

it’s actually called a scotchbrite drum, not a mandrel

 

[TRTermite]

it’s actually called a scotchbrite drum, not a mandrel

View attachment 982509

I am going to GOOGLE this to see what sizes R available THANKS for sharing.+ Hydraulic cylinders are in the back of my mind.