56-62 Pinion Seal Install Question

[Bob B.]

[Joe L.]

Re: 56-62 Pinion Seal Install Question

Hi all,

I am trying to install a pinion oil seal for ’56-62 Corvette differentials. Here are two pics comparing the straight-sided original with the round-sided replacement. The one I took out has parallel sides that match the parallel sides of the shaft hole at the end of the differential.

The one that I cannot get to go in is the National 6818 that is supposed to be correct. But its sides are more rounded and crest in a lip or bulge just inward from the edge of the seal that is supposed to go into the hole.

Because it has this bulge, it will not go in like the old one. I tried the old one again just to check, and it starts easily since it has parallel sides that all go in at the same time.

All the new one does is just roll around and around depending on where I tap. You can see this where the color on the edges of the 6818 seal is rubbed away right up to the bulge.

If I get one part of the bulge a little farther in, then the opposite edge of the seal is against the outside edge of the hole and that edge bends and the seal is ruined. As you see.

So, is there another seal that has straight sides like the original did, or is there some trick I am missing?

Thanks,

Bob

Bob-----


National 6818 is the correct National part number for your application. However, I'm not sure that what you have is actually a 6818 or, possibly, it's a defectively manufactured 6818. Is the number 6818 stamped anywhere on the seal?

If it is a 6818 I think I'd either try to find another 6818 or, better yet, go with a seal from a different manufacturer. SKF 17727 would be another choice.