Help ID this timing Chain Cover

[Doug L.]

Will appreciate help identifying the timing cover shown in the attached photos.

Thanks-Dougphoto-131.jpgphoto-132.jpgphoto-133.jpgphoto-134.jpg

[Michael H.]

Re: Help ID this timing Chain Cover

The one in the left pic is a 2nd design 64-65.

[Doug L.]

Re: Help ID this timing Chain Cover

Thanks Michael. All photos are the same cover. Do you know the approximate change-over date for this cover? Can you tell me the difference between this cover and the one that preceeded it? It has been offered to me. My car is a mid-December 1963 built SHP '64 model year with 8" damper. Too early for this cover?

Thanks-Doug

[Joe L.]

Re: Help ID this timing Chain Cover

Will appreciate help identifying the timing cover shown in the attached photos.

Thanks-Doug[ATTACH=CONFIG]41846[/ATTACH][ATTACH=CONFIG]41847[/ATTACH][ATTACH=CONFIG]41848[/ATTACH][ATTACH=CONFIG]41849[/ATTACH]

Doug-----


I would say 62-68 with 8" balancer (i.e. SHP).

[Michael H.]

Re: Help ID this timing Chain Cover

Doug-----


I would say 62-68 with 8" balancer (i.e. SHP).

Joe,

There was a unique cover used for 62 through early 64. (see previous discussion) A new design with a different timing tab was used from 64-65.
I think the cover changed again for 66-68. I think the change was the configuration of the timing tab.

[Joe L.]

Re: Help ID this timing Chain Cover

Joe,

There was a unique cover used for 62 through early 64. (see previous discussion) A new design with a different timing tab was used from 64-65.
I think the cover changed again for 66-68. I think the change was the configuration of the timing tab.

Michael-----


Yes, I seem to recall that now as far as the 62-E64 go. Among other things, I think the welded-on tab faced upward instead of downward. I am unaware of the changes from 66-68. There very well may have been a change but I don't know what it is. Functionally, though, I think the cover pictured will work for any 62-68 with 8" balancer.

[Michael H.]

Re: Help ID this timing Chain Cover

Michael-----


Yes, I seem to recall that now as far as the 62-E64 go. Among other things, I think the welded-on tab faced upward instead of downward. I am unaware of the changes from 66-68. There very well may have been a change but I don't know what it is. Functionally, though, I think the cover pictured will work for any 62-68 with 8" balancer.

Joe,

I'm not near my old parts books now but I remember a few (parts of) the part numbers. I think the 62-E64 cover was one number different than the damper, somewhere around 381717X.

I don't remember the 64L-65 number but it's probably somewhere around 384xxxx.

There was another new part/number for 66-68 and it was in the range of 3880xxx which would tell me that this part was intro for the 66 model year.

I think the new cover timing tab for 66-68 was longer and included the "R" and one or two additional marks on the retard side of the plate.

Hopefully, folks with original early production 365-375 HP 64 cars can help nail down the point of change from 1st design to 2nd design cover/tab.

[Don H.]

Re: Help ID this timing Chain Cover

my May 1 65 parts catalog shows 62-65 8" balancer as 3817173
and the crankcase front cover for 62-65 all SHP (exc 396) as 3851549

[Joe L.]

Re: Help ID this timing Chain Cover

Joe,

I'm not near my old parts books now but I remember a few (parts of) the part numbers. I think the 62-E64 cover was one number different than the damper, somewhere around 381717X.

I don't remember the 64L-65 number but it's probably somewhere around 384xxxx.

There was another new part/number for 66-68 and it was in the range of 3880xxx which would tell me that this part was intro for the 66 model year.

I think the new cover timing tab for 66-68 was longer and included the "R" and one or two additional marks on the retard side of the plate.

Hopefully, folks with original early production 365-375 HP 64 cars can help nail down the point of change from 1st design to 2nd design cover/tab.

Michael-----


Here they are:

1962-63-----GM #3817174

1964-65-----GM #3851549

1966-68-----GM #3885048

Each of the last two of the above became SERVICE for the previous covers.

Also, while there were only these 3 part numbers it's very possible that there were minor differences within each part number.

[Alan D.]

Re: Help ID this timing Chain Cover

62-63 w/oil seal 3817174 and 64 w/oil seal 3851549 (from Oct 1, 63 Chassis P & A Cat)

[David L.]

Re: Help ID this timing Chain Cover

Here they are: 1962-63-----GM #3817174 1964-65-----GM #3851549 1966-68-----GM #3885048

Joe,

I agree with most of your list but this is what I have found:

62-63 w/F.I., S.H.P.----GM # 3817174

64-65 W/F.I., S.H.P.----GM # 3851549

66-67 w/S.H.P. ---------GM # 3885048

68 w/S.H.P. ------------GM # 3923290
GM # 3923290 is listed in my 1968 Chev. Parts Catalog (Oct. 1967) only for the 68 Corvette 327 w/S.H.P.

From Chev. Parts History (service parts sold over the counter):
3817174 ----- replaced in Jan. 1964 by 3851549 ----- replaced in May 1966 by 3885048 ----- replaced in Jan. 1968 by 3923290 ----- replaced in 1977+/- by 361925 (disc. April 1985).

Enclosed is a page from one of my note books. I believe that the tab on the 66-67 and 68 timing covers for the 8" balancer probably use the large tab.

Dave

[Michael H.]

[David L.]

Re: Help ID this timing Chain Cover

Corrected: The space between timing marks is 2 degrees.

I don't have a timing cover from an original 1966-1967 w/8" balancer but I do have a timing cover from a 1966 w/6" balancer as shown in the 2 photos below. The timing cover tab is marked from -16 degrees to +16 degrees and the fold is up. The measured distance from -10 degrees to +10 degrees (10 timing spaces) is about 1.08" or about 0.108" per timing space at a radius of about 3 1/8" (tab to center of C/S hole).

I assume the tab on a 1966-1967 Timing cover w/8" balancer would be similar in shape but the distance between degree marks would be approximately 4.125"/3.125" X 0.108" = 0.143" per timing space. The measurement between the -10 degrees to the +10 degrees (10 timing spaces) would be approximately 10 X 0.143 = 1.43" or about 1 7/16". The tab would be approximately 4 1/8" from the center of the C/S hole and the fold would be down.

Someone must have a photo of a 1966-1967 timing cover w/8" balancer to verify my assumptions.

BTW, I have noticed that the 1967 timing covers are date coded on the front face at the center. I once had one that was stamped "1" and "67" (week #1 of 1967, I believe).

Dave

[Michael H.]

Re: Help ID this timing Chain Cover

I do have a timing cover from a 1966 w/6" balancer as shown in the 2 photos below. The timing cover tab is marked from -8 degrees to +8 degrees and the fold is up. The measured distance from -5 degrees to +5 degrees is about 1.08" or about 0.108" per degree at a radius of about 3 1/8" (tab to center of C/S hole).


Dave

[David L.]

Re: Help ID this timing Chain Cover

You are correct. Each mark is 2 degrees. I will correct my mistake in my previous post so as not to confuse anyone.

Dave