A little help with Engine Mount Bolts

[Joseph A.]

Re: A little help with Engine Mount Bolts

That is the bolt that I have in my car.

[David L.]

Re: A little help with Engine Mount Bolts

That is the bolt that I have in my car.

Joseph,

I assume that you mean the 399803 bolts that were on your 1969 that you have owned for 40 years.
My 1970 Corvette AIM (UPC 6, Sheet B3) lists GM # 3980701 as the engine mounting assembly, GM #399803 for the engine mounting bolts, and GM # 9422299 as the nuts as per the revision record dated 6-2-69. As I remember the 1969 Corvette production ended in Dec. 1969.

What is the body build date of your 1969 Corvette?

Based on my research the 3980701 mount assembly, 399803 bolts, and 9422299 nuts are correct for "late" 1969 and 1970 Corvettes.
I must have sold my NOS 3980701 engine mount a few years ago, maybe back in 2011, as shown in the link below.

https://www.forums.ncrs.org/showthre...3980701+mounts

Dave

[Joe L.]

Re: A little help with Engine Mount Bolts

Joseph,

I assume that you mean the 399803 bolts that were on your 1969 that you have owned for 40 years.
My 1970 Corvette AIM (UPC 6, Sheet B3) lists GM # 3980701 as the engine mounting assembly, GM #399803 for the engine mounting bolts, and GM # 9422299 as the nuts as per the revision record dated 6-2-69. As I remember the 1969 Corvette production ended in Dec. 1969.

What is the body build date of your 1969 Corvette?

Based on my research the 3980701 mount assembly, 399803 bolts, and 9422299 nuts are correct for "late" 1969 and 1970 Corvettes.
I must have sold my NOS 3980701 engine mount a few years ago, maybe back in 2011, as shown in the link below.

https://www.forums.ncrs.org/showthre...3980701+mounts

Dave

Dave-------


I'm not so sure that locking style mounts were ever originally used on a 1969. I can say, for sure, that my original owner, mid-September, 1969 built convertible was originally equipped with non-locking style mounts. There is no revision record in the 1969 AIM that indicates that locking style mounts were used. There was a different mount used in late 1969, GM #3967767, but I am almost certain that this was a non-locking style mount and, I highly suspect, the one that my car was originally fitted with.

In order for a locking style mount to have been used for 1969 small blocks, the lower RF ignition wire shields would have had to be different than the ones used for early 1969. There is no indication in the 1969 AIM that there was any change in the lower ignition shields. Of course, it could be that the copy of the AIM that we use today was never updated to reflect such a change. But, I kind of doubt that.

[David L.]

Re: A little help with Engine Mount Bolts

Dave-------


I'm not so sure that locking style mounts were ever originally used on a 1969. I can say, for sure, that my original owner, mid-September, 1969 built convertible was originally equipped with non-locking style mounts. There is no revision record in the 1969 AIM that indicates that locking style mounts were used. There was a different mount used in late 1969, GM #3967767, but I am almost certain that this was a non-locking style mount and, I highly suspect, the one that my car was originally fitted with.

In order for a locking style mount to have been used for 1969 small blocks, the lower RF ignition wire shields would have had to be different than the ones used for early 1969. There is no indication in the 1969 AIM that there was any change in the lower ignition shields. Of course, it could be that the copy of the AIM that we use today was never updated to reflect such a change. But, I kind of doubt that.

Joe,
It seems odd that the 1970 Corvette AIM (UPC 6, Sheet B3) had a revision on June 2, 1969, when the 1969 Corvettes were made until December 1969. I certainly can not explain this.
Dave

[Joe L.]

Re: A little help with Engine Mount Bolts

Joe,
It seems odd that the 1970 Corvette AIM (UPC 6, Sheet B3) had a revision on June 2, 1969, when the 1969 Corvettes were made until December 1969. I certainly can not explain this.
Dave

Dave-------


Yes, I'm very aware of that. In fact, it's one of the things that makes me believe that late 1969's did not get the locking style mounts. Given the early revision date, there would have been plenty of time to get the change to the locking style mounts into the 1969 AIM if there was an intention to use the locking style mounts for 1969. What this also says to me is that the late 1969 non-locking style mount was originally intended for use for 1970 but that intention changed way before 1970 went into PRODUCTION.

Also, the 1970 U-69, sheet A5 drawing shows "redrawn and redesigned" on 2/5/70 and includes the necessarily revised lower RF ignition shields. These never appear in the 1969 AIM.

[Joseph A.]

Re: A little help with Engine Mount Bolts

Joe;

I found this photo of an unrestored 1969 L88. This is the engine mount to frame bolt that my car came with, I know every one states Cad with slit nut but my car had this setup, it is an end of Jan 69 car. Phosphate bolt with self locking nut. Note the engine mount is non interlocking.

Eng Bolt.jpg

Regards,

Joe

[James G.]

Re: A little help with Engine Mount Bolts

Joe;

I found this photo of an unrestored 1969 L88. This is the engine mount to frame bolt that my car came with, I know every one states Cad with slit nut but my car had this setup, it is an end of Jan 69 car. Phosphate bolt with self locking nut. Note the engine mount is non interlocking.

[ATTACH=CONFIG]105409[/ATTACH]

Regards,

Joe

Side note - does anyone know if the oil filter in this photo is the original? or if someone replaced it with the black printed version - if original this would go a long way to clearing up the questions regarding the use of this filter as assembly line installed.

[Dave S.]

Re: A little help with Engine Mount Bolts

James,
I thought the same thing when I saw the photo. The black/white PF25 discussion is an interesting one.

[Terry M.]

Re: A little help with Engine Mount Bolts

There is reference to the white/black oil filter in the both the 1968-69 & 1970-72 TIM&JG. This is the first picture we have seen of that filter on a Corvette. That said the detail in this picture is somewhat lacking.

Save: I should have tried to outbid you.

[Dave S.]

Re: A little help with Engine Mount Bolts

There is reference to the white/black oil filter in the both the 1968-69 & 1970-72 TIM&JG. This is the first picture we have seen of that filter on a Corvette. That said the detail in this picture is somewhat lacking.

Save: I should have tried to outbid you.

Terry,
It is here safe and sound. It will find its way to the right destination. As you mention it would be nice to see some detail. It will need the BEST WAY......embossing on the bottom

[Joseph A.]

Re: A little help with Engine Mount Bolts

The bottom of this filter is not embossed

Oil Filter.jpg

[Joe L.]

Re: A little help with Engine Mount Bolts

The bottom of this filter is not embossed

[ATTACH=CONFIG]105423[/ATTACH]

Joseph------


I understand that the bottom is not embossed but would it be possible for you to post a photo of the bottom of this filter?

[Joseph A.]

Re: A little help with Engine Mount Bolts

This car had 28K miles on it so I am sure the filter was changed

[Dave S.]

Re: A little help with Engine Mount Bolts

This car had 28K miles on it so I am sure the filter was changed

Joe,
Any chance you might have a rough time frame of when that oil filter was installed.??
Trying to get some time frame for when these black/white PF25 oil filters were used.

[Ron G.]

Re: A little help with Engine Mount Bolts

Can anyone post a pic of one of the 6 bolts (3 on each side) that attaches the motor mounts to the block. After communicating with GB he informed me that the bolt is an indented hex head with usually an anchor for a logo. I have no doubt that GB is correct, but I am interested in the bolt size with an integral hex head. Thank you in advance for your effort and cooperation.