Cylinder wall rust.

[280z5368]

I took the engine appart planning on replacing seals and honing the cylinders since i bought the engine alone. Couple of things got in the middle and florida weather did his thing. Is it salvageable by honing only or is boring needed? I plan on going to a machine shop with him today but i dont know what to expect. In case of boring does it mean that new pistons are required?

[texasz]

Looks like surface rust to me, in which case it would come off easily.  If you do have (or choose) to bore the you will need larger pistons (or you could consider sleeving the cylinders, though I think larger pistons would be much more cost effective).

[280z5368]

Just now, texasz said:

Looks like surface rust to me, in which case it would come off easily.  If you do have (or choose) to bore the you will need larger pistons (or you could consider sleeving the cylinders, though I think larger pistons would be much more cost effective).

I can feel the surface difference on the cylinders, they will measure the clearances, I never been to a shop before. Hopefully no need to bore. Im not certain on how much sleeving could cost

[S30Driver]

Hard to tell by the pictures, looks like just surface rust.   The machine shop will check to see if the bores are in spec for taper.  If they recommend the re-bore, you are likely looking at a new set of oversize pistons and rings.

[siteunseen]

I agree with surface rust. They can run a geglazer or hone down and clean that off.

 

[280z5368]

1 minute ago, siteunseen said:

I agree with surface rust. They can run a geglazer or hone down and clean that off.

 

Hopefully, definitely learned a lesson on this one. I wanted to run one of those myself but at this point just leave it to them and start rebuilding soon.

[280z5368]

I got the engine back and although they cleaned the cylinders I expected more on the hot tank. Is my first time so idk if is supposed to look like that

[texasz]

So was it just surface rust or did they bore the cylinders? 

[Patcon]

I'm not surprised it didn't come cleaner. The chemicals get less and less aggressive every year

[siteunseen]

The core plugs are really bad, people don't see that. I had mine hot tanked and then dug and chipped at the rear to get a little more. The cylinders look good, cross hatch I think they call it. You could dig more calcium out but that could break free on down the road. I think I would let it go as is, they did and they're day in and day out guys. Trust is tough but you have to on these old cars. Now when it blows up don't get mad at me. 

 

[siteunseen]

Well wait a minute. They hot tanked it and it didn't get that blue paint off?

Maybe they just honed the cylinder walls?

Yep, I think your cylinder walls were just honed. Every block I've had dipped came back nothing but steel. No paint.

Edited May 1, 2021 by siteunseen

[280z5368]

1 minute ago, siteunseen said:

The core plugs are really bad, people don't see that. I had mine hot tanked and then dug and chipped at the rear to get a little more. The cylinders look good, cross hatch I think they call it. You could dig more calcium out but that could break free on down the road. I think I would let it go as is, they did and they're day in and day out guys. Trust is tough but you have to on these old cars. Now when it blows up don't get mad at me. 

 

Yes, that's the main reason I send it to get hot tank, maybe if I had it baked instead, but is too late. I wish I had more to reduce that but the passages are as clear as they are goinf to get. Crosshatch I think could have been done better, looks kind of wavy not straight.