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Rusty Cylinders, what to do?

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I've been working on my latest project, a 99 outback that I got for 600 bucks with a bad rod bearing.

 

I got a shortblock from another board member, and haven't looked at it until tonight. I was so excited to get everything all swapped onto the new block that I didn't even think to check the cylinder walls. This is what I found tonight. I scrubbed them up a bit with a scotch brite pad and some oil. This is after the scrubbing:

 

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This is as deep as I have ever been into an engine, and at this point I don't know what to do. The quicker and easier the fix the better, not really wanting to pull the pistons and re-hone. does this need a hone, or is there something else I could try first?

 

Thanks!

 

 

Time for a full rebuild or a different short block I'd say.

Sadly the block will need to be honed at least to be usable.

 

TOONGA

if you dont have to smog it i say run it only realy need to hone it if your installing new rings those rings are already mated to the cylinder worst that will happen is you will get some blow by and burn oil the rust is mostly above the ringlands the rest will go away real fast once that piston starts moving ive run alot of motors in ruff shape like this one 20141114_100218_zpsdlw6sc6a.jpg

 

just clean it up and run it

^^^ Because once you split the case open it never ends... until it's all new again   ;)

Edited by Crazyeights

Scotchbrite may not be rough enough for steel. Try some fine Emory paper or steel wool. Rub in a crisscross angle pattern. You don't need to remove all of the rust, just make it smooth. The engine will take are of the rest as its running. I've run engines with much worse in the cylinders without cleaning them at all.

  • Author

Thanks for the input guys, I took it down to a local shop today to get some advice in person. I told him I was leaning towards using some really fine grit sandpaper with lots of wd40. He didn't see a problem with that. I tried as best as I could to do it in an angled crosshatch pattern. Didn't get them sparkling, but they were pretty smooth. At this point I don't really have the time or the money to pursue other routes so this is just gonna have to work. Hopefully it won't run into issues anytime soon.

Oops. My error.

 

O.

Edited by ocei77

I put heads on a block worse than this. I used ATF and marvel oil and rotated the crank to polish it down, rinsing the crud out with WD40 after each rotation. 

^^^ I have too and I cringe when I start them. Most of the time they are just fine. I WOULD NOT do this on a customers car however.

Perhaps steel wool would be best as it would remove the rust but not polish down tolerances. Maybe even some coca-cola with that steel wool. 

  • Author

Miles, I'll try that if there is ever a "next time." This motor is all back together and ready to go back in the car tomorrow. Except for the pesky centering pin stuck in the old shortblock..

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