crank scored ,lined?

[n0n0_1963]

I replace the old rope seal by a two pieces viton seal viton on my 6.2 and the leak still there. After been so tire to clean the driveway and put a cardboard under the truck every time I stop I decide to redo the job and pay more attention to it.
I found out the the mating surface where the seal is sitting is not highly polished like on the rear bearing for example and some fine line are showing , they are regulary spaced, on short and one long, around 5 & 10 mm, and at 30 degree out of the alignment of the crank ...
Did anybody get the same thing?

[britannic]

I just replaced my rear seal and found that someone had already the replaced the old rope seal with the new one. The reason it was still leaking, was because they hadn't set the seal ends to 2 o'clock and 8 o'clock, but had instead line them up with the main bearing cap.

I noticed there was a very faint score line in the middle of the bearing and guessed it was probably caused by a piece of grit during the previous R&R. It was so minor, that I didn't bother to replace the bearing.

[CleviteKid]

Hello n0n0_1963,

What you may be seeing is a pattern designed to pump oil back toward the sump and away from the outside. I have not seen this on GM diesel crankshafts before, but some seals are designed this way to minimize loss of the fluid being contained.

This might work with a rope seal, but I would be concerned about the lines causing rapid wear of a lip seal.

Dr. Lee :cool:

[n0n0_1963]

Hey Britannic, did you see the little line on the crankshaft itself that I'm writing in my previous post, too bad that I didn't think to take a picture. :(
It's look like the tiny grove was "factory made" the space between and the lenght are in very regular patern. :confused:

[britannic]

My crankshaft was smooth without any lines/scores on it, which is why I wasn't worried about the slight score in the bearing.

Would you describe the lines/grooves as being similar to a widely spaced screw thread?

[britannic]

Originally posted by n0n0_1963:

I found out the the mating surface where the seal is sitting is not highly polished like on the rear bearing for example and some fine line are showing , they are regulary spaced, on short and one long, around 5 & 10 mm, and at 30 degree out of the alignment of the crank ...
Did anybody get the same thing? I just re-read your post. I think you're actually talking about the surface that contains the seal itself? Did you already put it back together?

If I understand your question, then these lines may be for gripping the seal?

Let us know if we're on the right track.

[n0n0_1963]

I think the Dr Lee is right, they are probably made to hold the oil outside by pushing back the oil when the crankshaft is spinning since they are against the rotation.
Now my ral concern is what kind of seal I should use, the viton are very easy to install and the rope a real pain.
I install a Banks and change the CDR valve, and check the vacum, it is at the Chevy spec.
Anybody had some positive experience with the rope seal? :rolleyes:

[britannic]

Viton is the way to go with a turbo; the rope type is OK for N/A, but doesn't have the same life expectancy.

It may be worth checking with GM's tech. department to see if the viton seal is compatible with your crankshaft.