CRG Discussion Forum
Welcome, Guest. Please login or register.
Did you miss your activation email?
September 01, 2014, 07:02:51 AM

Login with username, password and session length
Search:     Advanced search
Welcome to the CRG Discussion Forum!
Forum registration problems: Make sure you enter your email correctly and you check your spam box first. *Then* email KurtS2@gmail for help.
103754 Posts in 12185 Topics by 4697 Members
Latest Member: bobs67
* Home Help Search Login Register
+  CRG Discussion Forum
|-+  Camaro Research Group Discussion
| |-+  Originality
| | |-+  Original long bolts for 1969 L/78 motor mounts
« previous next »
Pages: 1 [2] 3 4  All Print
Author Topic: Original long bolts for 1969 L/78 motor mounts  (Read 13196 times)
nuch_ss396
Member
***
Posts: 265



View Profile Email
« Reply #15 on: February 28, 2009, 07:59:50 PM »

Original motor mount to engine block bolts:

Note that the left side bolts ( 3768390 ) are longer than the right side bolts ( 3748038 )
to compensate for the thickness of the stop bracket.




Logged

69 SS 396, Hugger Orange, D/80, D/90
Chambered Exhaust, N/66, THM400, 3:73 posi

Steve A.
  CRG
nuch_ss396
Member
***
Posts: 265



View Profile Email
« Reply #16 on: February 28, 2009, 08:12:03 PM »

WHEW!  Shocked Grin  Glad that's over with.  Roll Eyes

OK, now for some observations & questions:

1) Were the motor mounts assembled to the block prior to the BB painting process at Tonawanda?
    Would there have been any orange over spray on these motor mounts ( see the original mounts at the beginning of this thread )?

2) Were the BB motor mounts 3920627 ( 3937930 ) used throughout the 1969 production year?
    When were these mounts discontinued from production use?  Why do these mounts have two different part numbers molded on them?
    When was the left side stop bracket assembly discontinued from production?  Did it make it into the 1970 model year?

3) When did the BB engine frame brackets 3980941 & 3980942 replace 3950113 & 3950114?

4) Using the AIM as a reference, no part number could be found for the right hand long motor mount bolt.
    Extrapolating on the information I could find, it appears that possibly the standard 8 cylinder long motor mount bolt: 3980716 appears to be
    the correct part number for use on the passenger side motor mount of the 302, 350, 396, and 427.  See AIM page 87.  Can someone
    reference a 1969 parts manual and tell me if I am correct in my assumption?

So sorry to all the Z/28 & L/48 guys here.  Until I got into the research on this topic, I didn't know that the these cars used a similar stop bracket.  Odd that
a thru bolt and nut assembly was used on the Z & SS and the big block used the threaded receiver.  Are there any Z/28 or L/48 owners here that can post images of
their motor mount components?  I'd like to see them for comparison purposes.

OK - I welcome responses.

Nuch

« Last Edit: February 28, 2009, 08:25:32 PM by nuch_ss396 » Logged

69 SS 396, Hugger Orange, D/80, D/90
Chambered Exhaust, N/66, THM400, 3:73 posi

Steve A.
  CRG
1968RSZ28
Hero Member
*****
Posts: 4688



View Profile
« Reply #17 on: February 28, 2009, 10:14:54 PM »

Nice job Steve!  I think your ready to write a CRG report on this topic...   Wink

Paul
Logged
Pex68
Member
***
Posts: 393



View Profile Email
« Reply #18 on: March 03, 2009, 09:35:01 AM »

Ok, so obviously this is a 69 only thing so I can't offer any help specifically to the parts.  Was is interesting to me though is upon looking in my AIM for 68 there is a little bracket 3945413 listed as STOP-ENG MOUNT L.H. & specific bolt called out for it 3786494.  It was added 3-5-68 so I guess that why I don't have it on my car (12D) Assuming these things (stop brackets) were GM's first attempts to cure the breaking mounts?  I clearly see how the 69 mount worked (although think it would have just ripped the bolt out as there's really not much thread contact in that 69 mount) but what the heck was that little bracket supposed to do in 68???



Also, Steve, I beleive if the AIM shows an assembly process, then it was done on the engine dress line and at that point the engine would already have been painted so no overspray on the mounts.  I looked at this way when doing mine, NO AIM process for valve covers, distributor, or bell housing and they all had overspray on them.

Wish I could help more with this...69 guys need to chime in!!!
Logged

Chris P
1968 Sequoia Green SS 396/325 M20
JohnZ
CRG Member
*****
Posts: 4078


View Profile Email
« Reply #19 on: March 04, 2009, 10:13:06 PM »

Also, Steve, I beleive if the AIM shows an assembly process, then it was done on the engine dress line and at that point the engine would already have been painted so no overspray on the mounts.  I looked at this way when doing mine, NO AIM process for valve covers, distributor, or bell housing and they all had overspray on them.

Wish I could help more with this...69 guys need to chime in!!!


That's correct - anything illustrated in the Assembly Manual with a part number callout was installed at the car assembly plant; that's the easiest way to determine which part was installed where.
Logged

'69 Z/28
Fathom Green
CRG
nuch_ss396
Member
***
Posts: 265



View Profile Email
« Reply #20 on: March 06, 2009, 10:39:22 PM »

Makes sense - so how did they keep orange paint from clogging the threaded bolt holes for the motor mounts?

Steve
Logged

69 SS 396, Hugger Orange, D/80, D/90
Chambered Exhaust, N/66, THM400, 3:73 posi

Steve A.
  CRG
JohnZ
CRG Member
*****
Posts: 4078


View Profile Email
« Reply #21 on: March 07, 2009, 02:08:30 PM »

Makes sense - so how did they keep orange paint from clogging the threaded bolt holes for the motor mounts?

Steve

They didn't - there was no attempt made to mask any of the threaded holes in the block during engine painting - only the fuel pump attaching area was masked.
Logged

'69 Z/28
Fathom Green
CRG
nuch_ss396
Member
***
Posts: 265



View Profile Email
« Reply #22 on: March 07, 2009, 04:06:03 PM »

John,

Got it - thanks.

Did you ever see the engine painting process using the reported vac-forms that masked the aluminum intakes from paint? 
This topic has long been talked about over on the NCRS.org forum and is one of those research topics I am quite interested in. 

Steve
Logged

69 SS 396, Hugger Orange, D/80, D/90
Chambered Exhaust, N/66, THM400, 3:73 posi

Steve A.
  CRG
JohnZ
CRG Member
*****
Posts: 4078


View Profile Email
« Reply #23 on: March 08, 2009, 03:50:06 PM »

Did you ever see the engine painting process using the reported vac-forms that masked the aluminum intakes from paint? 

Yes - I worked at the Chevrolet Pilot Line, almost next-door to Flint V-8, from 1966-69 (a friend of mine ran the Flint V-8 Piston Department); Flint V-8 made the vacuum-formed plastic masks in their toolroom.
Logged

'69 Z/28
Fathom Green
CRG
nuch_ss396
Member
***
Posts: 265



View Profile Email
« Reply #24 on: March 08, 2009, 10:51:04 PM »

John,

To the best of your recollection, has anyone ever documented that process
with pictures taken during the engine painting process?  Did any of these masks
make it out of Tonawanda and into someones collection?  I'd love to see one...... Grin

Steve
Logged

69 SS 396, Hugger Orange, D/80, D/90
Chambered Exhaust, N/66, THM400, 3:73 posi

Steve A.
  CRG
crobjones2
Member
***
Posts: 287


View Profile
« Reply #25 on: March 09, 2009, 12:13:43 AM »

Did you ever see the engine painting process using the reported vac-forms that masked the aluminum intakes from paint? 

Yes - I worked at the Chevrolet Pilot Line, almost next-door to Flint V-8, from 1966-69 (a friend of mine ran the Flint V-8 Piston Department); Flint V-8 made the vacuum-formed plastic masks in their toolroom.

John
were several different motors built at the same time?  for instance the Corvette motors alongside the Camaros?
Logged

Chris
69 SS 350
JohnZ
CRG Member
*****
Posts: 4078


View Profile Email
« Reply #26 on: March 09, 2009, 03:16:37 PM »

John,

To the best of your recollection, has anyone ever documented that process
with pictures taken during the engine painting process?  Did any of these masks
make it out of Tonawanda and into someones collection?  I'd love to see one...... Grin

Steve

If I had known 40 years ago it would be important today, I'd have taken pictures Smiley. No, I don't have any photos of the Flint V-8 paint process, have never seen any, and the GM Media Archives doesn't have any either. The only photo I have is of the Tonawanda paint line, but it doesn't show the masks - the only engines Tonawanda built that used intake masks were tri-power and solid-lifter big-blocks.
Logged

'69 Z/28
Fathom Green
CRG
JohnZ
CRG Member
*****
Posts: 4078


View Profile Email
« Reply #27 on: March 09, 2009, 03:21:07 PM »

John
were several different motors built at the same time?  for instance the Corvette motors alongside the Camaros?

Yes. Both Flint V-8 and Tonawanda built 300-320 engines per hour, 16-18 hours per day (one every 12 seconds), and they typically ran 30-40 different suffix codes every day, with a mixed schedule.
Logged

'69 Z/28
Fathom Green
CRG
Pex68
Member
***
Posts: 393



View Profile Email
« Reply #28 on: March 12, 2009, 12:59:20 PM »

What's the correct finish for the motor mount through bolts and nuts?  I always thought they were black phosphate but just ordered a set from AMK and their both clear zinc!!!  Is that right???  Also just have a simple "A" on the head with GR 5 marks...what's correct?  Speaking of 68 396 application. 
Logged

Chris P
1968 Sequoia Green SS 396/325 M20
firstgenaddict
Hero Member
*****
Posts: 1203



View Profile WWW
« Reply #29 on: May 25, 2009, 08:37:44 PM »

Here is an Original Early 69 Z Engine Mount, this was on the right side of the 10D 69 Z I am restoring now.
I assume the left would have originally been the same with the limit assembly including the long bolt and spacer, however this car had a later interlocked one on the left.
It also uses a threaded reciever which is blind so I have no idea what the nut reference is in the AIM.





The difference from the BB is the chunk of rubber with the threads is opposite and the BB doesnt have the elongated cutout along the bottom where the lower hole is.
Logged

James
Collectin' Camaro's since "Only Rednecks drove them"
 
Check out the Black 69 RS/Z28 45k mile Survivor and the Lemans Blue 69 Z 10D frame off...
https://picasaweb.google.com/112392262205377424364/1969_Z28_Restoration
Pages: 1 [2] 3 4  All Print 
« previous next »
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!
Page created in 0.325 seconds with 17 queries.