CYLINDER WALL MARKS.

kyle43335 · Apr 23, 2012

just tore the heads off a customers truck,and i found these.

customer did his own gasket job,then they blew a week later(arps and bo gaskets)

you can catch your nail in them.

these 2 are located inward from where the studs screw into the block.

there are others,in some of the other cylinders.

going to talk to my customer.

i feel the engine needs to be pulled,pressure tested,and if pass? bored.

discuss.

SootPowered · Apr 23, 2012

looks like the engine may have set up for a while and the rings seized to the cylinder wall. Really hard to say where it come from. I would say pull and at least have the cylinders honed.

Mdub707 · Apr 23, 2012

You can't really just hone a scratch out though. It really should be bored like he said.

Those are some really odd markings though. I'd be interested to see what the heck caused that. I'll be tearing my heads off soon, crossing fingers that the cylinder walls look good.

What I don't get is, besides those odd marks, the rest of the cylinder looks great.

kyle43335 · Apr 23, 2012

Mdub707 said:
You can't really just hone a scratch out though. It really should be bored like he said.

Those are some really odd markings though. I'd be interested to see what the heck caused that. I'll be tearing my heads off soon, crossing fingers that the cylinder walls look good.

What I don't get is, besides those odd marks, the rest of the cylinder looks great.

im worried theres a slight crack,or pin hole in one of these marks.

Triple H · Apr 23, 2012

Definetley looks like the engine was parked for awhile. There's a ghost of the piston in the top of the bore.

Are those scratches raised or below the bore surface? If they're raised, then I would think the thread bore was full of junk or liquid when the studs were installed or stud over torque. Block could be damaged. Would magnaflux work in the bore to check?

kyle43335 · Apr 23, 2012

Triple H said:
Definetley looks like the engine was parked for awhile. There's a ghost of the piston in the top of the bore.

Are those scratches raised or below the bore surface? If they're raised, then I would think the thread bore was full of junk or liquid when the studs were installed or stud over torque. Block could be damaged. Would magnaflux work in the bore to check?

their below.

the stud holes didnt look the best.

they used what looks like thread sealant as well.

Mdub707 · Apr 23, 2012

kyle43335 said:
im worried theres a slight crack,or pin hole in one of these marks.

Valid concern.

Triple H said:
Definetley looks like the engine was parked for awhile. There's a ghost of the piston in the top of the bore.

Yeah now that you mention it you can definitely see it in the second pic. Wow.

Worstenemy453 · Apr 23, 2012

That's from it doing alot of sitting. Have seen quite a few come through the shop like that. Never affects running, or anything like that, but is definetaly something that makes you sit back, and scratch your head.

kyle43335 · Apr 23, 2012

Any other thoughts?

java · Apr 23, 2012

I wouldn't think there would be a pinhole. Mine looked like this and I just bored it .040 over and it worked great with EDE pistons. I did have the block tested and all checked out.

Triple H · Apr 23, 2012

Low spots in the casting, eh?

wetnsloppy4x · Apr 24, 2012

Triple H said:
Definetley looks like the engine was parked for awhile. There's a ghost of the piston in the top of the bore.

Nice catch. I missed that too on the first look.

That cross hatch looks amazing though. What kind of mileage is this motor supposed to have Kyle? In the second pic it looks like the mark/gouge is nearly straight across. Is that right? It makes me wonder what that skirt looks like. It also makes me wonder how far the customer torqued the studs and how he did it. Are you thinking what I think you're thinking?

Java, your pic is scary man. A possible casting flaw in the cylinder? Yikes. Either that or some something bad happened in that hole in the past and someone cleaned it up the best they could. Or do you mean this was before the .040 over?

09stroker · Apr 24, 2012

That picture was taken on the stock motor before any machine work. .040 was necessary because .020 would not clean up the pitting.

wetnsloppy4x · Apr 24, 2012

09stroker said:
That picture was taken on the stock motor before any machine work. .040 was necessary because .020 would not clean up the pitting.

OK. I get it now. I appreciate the clarification. Was that a motor that blew a HG and sat for a while? [/derail]

kyle43335 · Apr 24, 2012

wetnsloppy4x said:
Nice catch. I missed that too on the first look.

That cross hatch looks amazing though. What kind of mileage is this motor supposed to have Kyle? In the second pic it looks like the mark/gouge is nearly straight across. Is that right? It makes me wonder what that skirt looks like. It also makes me wonder how far the customer torqued the studs and how he did it. Are you thinking what I think you're thinking?

Java, your pic is scary man. A possible casting flaw in the cylinder? Yikes. Either that or some something bad happened in that hole in the past and someone cleaned it up the best they could. Or do you mean this was before the .040 over?

this motor has 77,000 miles

i cant see this happening from siting.

javas pic yeah def. his looks like rust...

the marks in this cylinder have a sharp edge.
looks like the wall moved around the stud bores slightly,and the ringing have been shaving it.

java · Apr 24, 2012

wetnsloppy4x said:
OK. I get it now. I appreciate the clarification. Was that a motor that blew a HG and sat for a while? [/derail]

That is from my daily driver, it puked with ARPs and when we took it apart thats what we found. I was told that it could have been from my water/meth.
Sorry for the derail OP.