Cylinder bore question with pictures
 

This is my number 4 cylinder... any idea what is going on? These marks are square with the bore, so it can't be water, you can definitely feel these marks.. the home was fresh at the beginning of this season. This is the only bore that did this.. thanks for any ideas.

Chad Dammen

Are you running alcohol?

Have any head gasket problems?

Been out in the rain?

:confused:

Vp x16 race fuel

No head gasket problems

No rain..

The marks are about 80% around the cylinder and square to the deck... if it was water the line would be at a angle to the deck... this is why I am confused...

Engine sit for a long time without being cranked over?

Ring faces look any different on that cylinder?

Is the block filled to passed that point on the wall?

All of those vertical marks are a sure sign that at least the ends of the oil ring rails need to be rounded over , a lot of fiction getting introduced there!

The longest the engine sat was 2-3 weeks if that.

Haven't pulled the pistons out yet.

The block is not filled, it's aftermarket.

The ring pack is total seal classic race

.043/.043/3mm the short block turned over at 11-12 ftlbs. Well according to the cheap craftsman beam style tq wrench.

What has made you yank the head(s)?

If that's where the piston in 4 was sitting when you pulled the head, then it sure looks like signs of water to me, but I woukd not expect such to be showing rust pitting around 360 degrees of the Bore , only on the low side of the piston if the motor was sitting in a normal position.

You could have a leaky valve seat coolant wise?

Looking at the first shot again I see what I believe is a crack in the wall below those pit marks and just to the right of that second gas port hole.

I put the heads on at the beginning of this season , they were used and needed the valve job touched up... I just didn't have time earlier to do it so I lapped the valves and ran it... also the connecting rods are only rated to 850 hp and I was way above that, so I was going to upgrade my rods as well...

I was questioning if that was a crack also.. might have to get the block pressure checked...

If the chamber and plug from 4 look cleaner then the others then chances are it's from water.

A crack my not open without heat, a Mag test is the way to go and far faster and cheaper!
Way above 850 hp by means of NA?

It made 870 n/a and I was spraying a .026 jet in a fogger.. so 225-240 ish...

All the chambers and pistons looked the same, nothing was steam cleaned...

Well at any rate that cylinder needs to be confirmed as good or bad at this point!

If needed, can that one cylinder be sleeved?

Fully agree!

I would figure that would be the fix..

Is it a thin spot with coolant seeping in from the back side?

Pressure check along with a good sono of area. A sleeve should take care of it.

total seal gapless? did it use any oil?

Generally inside water jacket eventually gets rusted and the metal eventually gets thin spots with age.
Before new sleeve clean it good seal off with good anticorrosion paint best suited to task.(Rust-Oleum Specialty products)

BTW odds are you might see a darker shadow if you honed for a bit where you see rust now. The shadow might move some...but don't lose too much material just to play you'll need support for sleeve too.

Using VP fuel you can fog engine with fogging oil to stop it Q16 C11 C12 are a very dry gas with very little petroleum base oils and cyl. walls will rust. I seen the same thing in my super stock engine before i started fogging.
Greg Meyer

Classic ring..(std style)

Oil usage, not that I'm aware of.

You could put the heads back on and pressurize the cylinder and see if the cooling system starts building any pressure.

There is nothing wrong. The engine has not seated and you are using racing oil they have very little rust preventative in it. I had a 454 that had break in oil in it. Had to pull heads because valve guide seized. Set maybe a week. Pulled heads and was amazed at the amount of surface rust on cylinders On yellow bullet N/A section there was a thread started on it by the admin of that section. Rod Cole

Rod you posted about rust on all of your cylinders , he only has a issue with 1 cylinder!

One of my cylinders looked like that, water seeping in through the ported heads in my case.

That's why I mentioned valve seat issue until I saw what I precive to be a crack , but these Heads have 1/4" wall thickness which would take a ton of porting to breach thru, but heck ya never know!

My thought is that hole was the one with either valve open where the moisture came in. Real early in the rusting process. My opinion is if a crack would be more stain . Stain looks like a oil ring to me not crack. But I have been wrong a lot.

I've seen this in 6.9/7.3 IDI diesel blocks, but they are know to have problems with vibration induced cavitation. They also had 300,000+ miles on them. It is possible there could be porosity in the cylinder wall that is letting coolant out of the water passages and into the cylinder. I'd pressure check the block after I had it checked with dye penetrant.