Restoring Eccentric Adjusting Bolt (3820253)

[Joe L.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

I myself have taken apart the rear cam bolts on my cars 72/63 and they are splined at the at the end of bolt where the cam washer fits,it's likely pressed together.

Edward----


That makes sense. I've never taken one apart and it's not otherwise apparent but splines would ensure positive retention and prevent any rotation of the cam relative to the bolt.

[Joe L.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

I myself have taken apart the rear cam bolts on my cars 72/63 and they are splined at the at the end of bolt where the cam washer fits,it's likely pressed together.

Edward------


By the way, is your 1963 cam/bolt assembly the same as the 1972? Does the 1963 lack the "degree" marks on the attached cam?

[Edward J.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

Edward------


By the way, is your 1963 cam/bolt assembly the same as the 1972? Does the 1963 lack the "degree" marks on the attached cam?

Joe 63 has no degree marks and I have a 64 I will look at this later and get back to you, just in case they did not change.

[Jim D.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

I myself have taken apart the rear cam bolts on my cars 72/63 and they are splined at the at the end of bolt where the cam washer fits,it's likely pressed together.

Yes, it's pressed together. Stevie Wonder could see that they are not welded.

[Patrick H.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

Though I've been told that midyear cam/bolt finishes were the same, they're not my area. So, make your own extrapolations.

68-72 are as I noted above and as Joe has noted.
Below is a picture of a 3000 mile 72 that I found and had one of our members purchase. It's a gorgeous car.

Note the phosphated bolt with natural cam. I commented on the finishes to the now-owner as I was underneath inspecting the car.
I also have a picture of the other side of the bolt and cam, but we're not talking much about those.

The 68-9 manual doesn't directly comment on the adjusting cam we're discussing, it just mentions the black phosphate bolt. I'd have to look back in my notes to see if we purposely avoided mentioning it.

[Edward J.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

Heres a pic of a 64 camber adjustment bolt assy. Its been cleaned up and from the appearance it looks like it was black from the hardening process??, really cannot say if there was any zinc or cad ever on any parts. no degree marks either.

[Gary B.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

Picture of the other side. Ed Foss 4-mile car. As said in previous post, make your own extrapolations.

Gary Bosselman

[Edward J.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

Picture of the other side. Ed Foss 4-mile car. As said in previous post, make your own extrapolations.

Gary Bosselman

Gary, what year was the car? 68/72?

[Gary B.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

1971, yellow car. Big block.
Gb

[Terry M.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

1971, yellow car. Big block.
Gb

I thought that car was a 1972, but they all look alike from that view.

[Patrick H.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

The one I posted was a 72. However, the back side of it looked just like what Gary added above.

[Michael F.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

starting to get little personal guys, two good minds just can't agree on this one.

[Patrick H.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

I would not be surprised if the finish changed on the eccentric cam over the years. Gene is talking midyears, Joe is talking Sharks. They might both be correct, but as I noted in my post above I don't spend enough time under very low mile midyears to comment on them myself.

However, I learned years ago that the cam for 68 (who knows on those cars) to 72 should be natural, as I posted above.

[Joe L.]

Re: Restoring Eccentric Adjusting Bolt (3820253)

I would not be surprised if the finish changed on the eccentric cam over the years. Gene is talking midyears, Joe is talking Sharks. They might both be correct, but as I noted in my post above I don't spend enough time under very low mile midyears to comment on them myself.

However, I learned years ago that the cam for 68 (who knows on those cars) to 72 should be natural, as I posted above.

Patrick------

We know that 1963 was different, at least with respect to the degree markings. It's possible that later C2 had a different finish on the cam and bolt than C3, even though the part number never changed (at least until L1977). It's possible that the finish on a part could change without a change of part number. It would be interesting to hear from some 1964-67 owners with un-restored cars. The cam/bolt assembly and separate cam would not otherwise be oft-replaced parts.