Look at my Cylinder Wall

[Defiant]

I pulled the head cause #2 exhaust port was soaking wet in oil.

I suspect a broken ring, or a dirt behind a ring in the groove.

 

[terefic181]

Turbo 2g awd,

You should take a good look at the URL site below. It was originally brought up by 92redman. Look specificly at the portion on "Center Point Skirt Scuffing".

Since you said this was common across all your cylinders and not an isolated case, then oil ring would go way down on my list of probables. Your oil problem in the one cylinder may or may not be associated with the scuffing. The scuff area shown in the picture for "center point scuffing" is about the right size and level, it starts just below the oil ring and it's patern looks close also. I think it's an interesting prospect. The picture shows the piston but I'm sure you would have the same patern showing on the cyl wall.

http://www.tomorrowstechnician.com/tt/t230338.htm

 

[Turbo 2g awd]

Thanks guys for all the help. I also put up a post on the DSM Link forum. Most of them say it is normal in a race motor and not to worry. A coulpe of them have it in there own 2.0 or 2.3 motors. It will just take much longer for a stock motor to see it. With forged internals and high boost it will show up sooner. And the pic makes it look worse than it is. I can shine a light on it and see the hatchings still. It is on both the front and rear of the cylinder which is where the most of the pressure is from the way the crank rotates. And I also believe that the piston pin is a little offset towards the exhaust which would put a little more pressure on the back of the piston on the way down. Oh well not gonna worry about it. Just gonna run higher boost and race fuel. Once the head comes back I will see what the 3065 feels like with 28psi.

 

[red91gst]

http://www.hastingsmfg.com/Service Tips/piston_cylinder_scuffing.htm
http://www.engineproblem.com.au/piston_pickedup.htm
http://www.tomorrowstechnician.com/tt/t230338.htm

So if you want to know if it should look like that, why haven't you called the people that built the engine yet?

This would be a great idea if our pistons actually came out of the bore at the bottom of the cylinder, stop building chevy BBs and put a Mitsu motor together.

Please have experience with this before you quote a 30 year old motor resource.

Nate
SBR

This wear is common on a forged piston motor.

 

[TargeT]

Turbo 2g awd,

You should take a good look at the URL site below. It was originally brought up by 92redman. Look specificly at the portion on "Center Point Skirt Scuffing".

http://www.tomorrowstechnician.com/tt/t230338.htm

P

iston Crown Scuffing
Crown scuffing occurs when the piston rapidly exceeds normal operating temperatures. Typically, this is caused by an over-fueling condition, a result of either too much fuel or too little air. In some applications, a lack of oil cooling the crown can also cause rapid piston crown growth, resulting in a loss of crown-to-cylinder liner clearance, creating crown scuffing and possible seizure.

hahhaha, i pulled that from your link...

now tell me your going to take ANYTHING on that page seriously after reading that...

 

[terefic181]

Greetings TargeT,

hahhaha, i pulled that from your link...

Well, first of all, it wasn't my link, it was 92redman's link.......Secondly, I didn't review the whole article I addressed the part that we were discussing here, scuffing in a particular location.......and thirdly, I said "I think it's an interesting prospect"


Now.... the reason I said it was an interesting prospect... was do to the picture of the piston with the caption "Center Point Skirt Scuffing". The patern and location of the scuffing match pretty closely to the markings on the cyl wall in question. I simply pointed out the simmilarites in the patern and location of the two.

now tell me your going to take ANYTHING on that page seriously after reading that...

Nope........sorry I didn't read that, it wasn't what we were looking at.

:laugh:

 

[Doug99RS]

Here is a pick of my cylinder wall. Its a Slowboy Racing Ross/Eagle Stage II 6 bolt. The motor has 5 thousand miles on it. Is this marking ok???? I just took the head off to replace some leaking Valve stem seals.

What about the honing cross-hatches. Don't they look over-worked and too close together? This below below is another 4 cylinder but with higher mileage. The walls in here still have a semi mirror finish and the cross-hatch pattern can still be seen a little. Something just doesn't look right with the rest of the cylinder walls. Also, how were the piston rings lined up on installation? And what was the orientaion of the rings on removal? None of the gaps are supposed to line up with another.
Doug

 

[terefic181]

I'll take a shot at it, and go on the line.

From what I can see in the picture. The piston, cylinder left.

The rings were possibly put in, in line with one another, due to a continuous from top compresion ring to botom of throw distance, line. I believe the original orientation was probably north because this line looks to be older. The end orientaion, I would say looks to be west with possibly fresh carbon build up at that line. Also a probable blown gasket between the two cylinders with coolant contamination.