Oh no....Grooves in my cylinder wall!!!!
 

I hate it when this happens.

Got the new heads on (loose) last night and all I had to do tonight is put the bolts in and torque.
Realized that I might not have tapped all the block threads on passenger side so I pulled the head to check - and there it caught my eye....

A couple 1/2 inch long grooves in cyl #2. They are shallow - can't catch a nail on them but you can still feel them. They start about 1/4 inch from the top of the shiney marks on the wall, get gradually deeper, and then taper back to smooth. They are both the same length and about 1/2 apart.

All other cylinders look great - yes, I checked the other side too.

I'm afraid of the proper fix - no way I'm gonna do any major work at this point of time......

What do I do?
Leave them?
Can I polish them a little?

Help!

Dan

No prob yet bud, relax a little and tell me this, how far from the top of the block is the very beginning of the score to the end of it going down tward the block, lets start there and respond, built 51 302's as of last week.

Don't worry, I'm not that excited - just dissapointed that I could have run into a problem. I'm just asking for help from experienced people.

Starts a little less than 1/2 inch down from the top.

I mentioned that it starts below the top of the shiney part meaning that it starts below the top of the (ring) wear surface in the wall.

Where in the cylinder are they? If the cylinder was a clock, and the front of the engine represented 3 oclock, where are the marks?

They are aprox 6:00.

To explain it another way, as you look down at the block while standing at the passenger tire, they are at the outboard side of the cylinder.

Hope that makes sense.

Dan

Well, that rules out a piston pin problem!

Sounds like your 2nd comp. ring is broken. Don't stress it now, but I'll be willing to bet that the outside skirt on the #2 piston will have hairline cracks by the time it gets pulled.


http://homepage.mac.com/pkrwud/.Pict...%21/302.7.jpeg

Wow hows that for a reply, tells ypu and shows you whats wrong.

Nice:D

Thanks for the pics.
If it were a broken ring wouldn't the grooves go the lenth of the stroke? Right now the grooves are about a 1/2 inch long.

Not necessarily. The cylinder gets wider the farther down you go, plus the first inch the piston travels sees the most outward force. After that, the energy is directed down. You said the marks weren't deep enough to catch a nail on, so they're young. As time goes on, the grooves should lengthen, but it also depends on what the ring looks like. How many miles are on the short block? Did it recently see nitrous or a blower? Why are you swapping heads?

150k on the stock block.

Always been N/A

Why the heads? In search of more ponies:). They are just part of my overall upgrade. Someday I'll do the whole motor.

Dan