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A18A
07-12-2009, 09:41 PM
does this mean it needs to honed out or something? and is this caused by facked rings? or is it from having water sitting in it for 1 - 2 years?
http://img40.imageshack.us/img40/9476/1005908medium.jpg
http://img40.imageshack.us/img40/4051/1005910medium.jpg
also.. what do i need to know when choosing a motor to rebuild? (this one hopefully) all i know about it, is that it has done around 270000 - 300000km, mostly city, temp needle has been buried in the red zone one time in my ownership (possibly more in the past) and it smoked heaps of blue smoke under load. the head gasket looked okay when i pulled it apart though. if the head/block is cracked, should that be visable to the naked eye? or do they start out microscopic or something

of course i plan on doing loads more research before i continue.. i'm too poor at the moment anyway. just wanted to get your thoughts on this first before i waste any more time on this :) this is gonna be more for a learning experience than anything else for me as this would be my first build

Ayeobe
07-12-2009, 09:51 PM
Them cylender walls look prety messed up.
Anyone can correct me here, but..
For the head, its usually "microscopic" when it starts out. I dont rememebr exactly how to test it, but i know unless its a bad case, its not usually visible to the naked eye.
also, you'd need a straight edge for the measurement of wether or not the head is warped. That can cause coolant or oil or both to leak ither together or into the cylenders.
For the Cylender walls, theres a tool you attach to like an impact gun or drill that is like a brush and spins in the cylender to remove the rust and shit, but im not sure what the limit to how bad the walls can be before you cant do it anymore.
That also means you may need bigger Pistons and piston rings, though not by much probabily.

Well, good luck man.

2ndGenGuy
07-13-2009, 12:27 AM
With that many miles, you're going to want to bore that out. If you want a reliable engine, that is. After so many miles, the cylinders tend to get egg-shaped and really the only way to get rid of that is with an overbore. You may or may not be able to hone all that corrosion out, depending on how deep it is. Not that it matters, because you really should bore it and throw in oversized pistons.

The only thing that I know of that would make the cylinders bad is if the corrosion goes so deep that it's still there after a bore out. I'm not sure what the chances of that actually are. Probably best to get it bored oversize on just about any old block anyways...

If it's been overheated, make sure you get the block resurfaced and probably want to get the main bearing bores... uh rebored... :)

A18A
07-13-2009, 02:09 AM
sweet thanks for the info. i will probably ask a bunch of questions later, i just cant think of anything right now

if i take detailed photos of everything, would you guys be able to tell me more about the condition of it?

AccordEpicenter
07-13-2009, 02:52 PM
you should have it bored out. Also i would check the head for warping as well as the deck surface on the block. shitcan all the old pistons and get new ones to fit the new bore

Ichiban
07-13-2009, 03:07 PM
sweet thanks for the info. i will probably ask a bunch of questions later, i just cant think of anything right now

if i take detailed photos of everything, would you guys be able to tell me more about the condition of it?

Pictures don't really say fuck all. If a part is obviously scored or fucked out, you yourself are going to be able to tell. Otherwise you need to measure parts accurately with a micrometer to be able to tell whether it's good or not.

Things to measure:

Cylinder bores: Taper, out of round, ring ridge
Cylinder head/block decks: Warpage
Rod/main bearing journals: Taper, out of round, out of spec (undersize). End thrust.
Pistons: Wear, undersize, ring side play, wrist pin bores
Rods: Crank journal bores just love to go out of round. Side play on rod journal

...etc. This is just a list off the top of my head.

Dr_Snooz
07-13-2009, 07:13 PM
Pictures don't really say fuck all. If a part is obviously scored or fucked out, you yourself are going to be able to tell. Otherwise you need to measure parts accurately with a micrometer to be able to tell whether it's good or not.

Things to measure:

Cylinder bores: Taper, out of round, ring ridge
Cylinder head/block decks: Warpage
Rod/main bearing journals: Taper, out of round, out of spec (undersize). End thrust.
Pistons: Wear, undersize, ring side play, wrist pin bores
Rods: Crank journal bores just love to go out of round. Side play on rod journal

...etc. This is just a list off the top of my head.

I agree. It's hard to tell much of anything from the pics. That could just be simple discoloration or deep pitting. A good machine shop should be able to mike it out, pressure test it, etc. That will tell you a lot more than we can tell you looking at pics. A good machine shop is your best resource really.