Topic: Early 67 NJ - Firewall sound deadner

[sparky65]

Well I am getting down to the final details.  Probably was supposed to do this sooner but I still need to apply the sealer / sound deadner to the firewall.  I've been putting it off because its so hard to make a mess of the nicely finished engine bay.  Anyway does anyone have pictures of how it was applied at the NJ plant in 67?  Was there anything that should not be in place when this gets applied?

[J_Speegle]

Well I am getting down to the final details.  Probably was supposed to do this sooner but I still need to apply the sealer / sound deadner to the firewall.  I've been putting it off because its so hard to make a mess of the nicely finished engine bay.  Anyway does anyone have pictures of how it was applied at the NJ plant in 67?

Yes - will dig them out and post

Was there anything that should not be in place when this gets applied?

Yes the ground cable and mounting hardware - it was still attached to the engine which was out of the car

[sparky65]

Yes the ground cable and mounting hardware - it was still attached to the engine which was out of the car

Well I am not taking the engine out.  Its a I6 so hopefully I can work around it and just disconnect the ground.  Did they mask the ground cable connection point or just try to avoid it?

[Bob Gaines]

Well I am not taking the engine out.  Its a I6 so hopefully I can work around it and just disconnect the ground.  Did they mask the ground cable connection point or just try to avoid it?

The location where the ground went was avoided (no witness line from masking that I have ever found) on the fire wall because it had to be free of sound deadner so that when the ground was screwed down (also got a gold locking star washer )it would make good ground connection with the unibody .

[J_Speegle]

................ Did they mask the ground cable connection point or just try to avoid it?

Neither - it was not attached to the firewall (engine was on a stand or shelf at that point) when the sealant was applied. If you look at the 68 San Jose pictures as an example - When the engine is being installed - the sealant had already been applied and was in place at that moment.

Well I am not taking the engine out.  Its a I6 so hopefully I can work around it and just disconnect the ground.

IMHO it would be best (since your doing it this way)  to remove the screw that attaches the ground, tuck the ground wire out of the way, and reattach it after your done and the stuff has dried.  Might want to try the tin foil trick (one I use all the time) to wrap the back of the engine and top of the trans (anywhere you don't want the sealant overspray/drips). It molds to the part and is easy to remove

[J_Speegle]

............ Anyway does anyone have pictures of how it was applied at the NJ plant in 67?  Was there anything that should not be in place when this gets applied?

Ok here are some pictures (remember everyone without a 67 NJ car - these are not for YOUR CAR

Before you go spraying the sealant or what ever product you choose to us to reproduce the stuff make sure you have all the


1- electrical through the firewall

2- the brake lines and retaining hardware in place

3- speedo, throttle and clutch rods attached to or through the firewall with rubber boots in place

4- heater motor attached (all hardware in place)  wires connected, if you have a heater control valve its in place and attached. As well as heater hoses

5- any vacuum hoses that pass through the firewall in place

At that point make sure you seal around the heater hoses with a little dum - dum (3M strip chalking works well for this)




And  both screw covers in place over the mounting screws that pass through the firewall - Should typically be two. Different location depending on v8 or 6 cylinder it appears



In the following examples I used examples of fairly heavy applications of the sealant since they show up better that way and I highlighted the area I see covered or in some cases were it appears that there was sealant that fell off when rust developed behind it. ZRemember that the heater motor waould have been installed before the sealant application





Since you have a 6 cylinder non- PB car I choose examples that best matched these features





Remember when you apply the sealant the idea was to seal every screw, electrical connection/pass through or anything else that passed through the firewall. Not that they always got every thing most tried

As always  - Hope this helps

[sparky65]

Thanks Jeff this helps a lot.  Just a few questions

And  both screw covers in place over the mounting screws that pass through the firewall - Should typically be two. Different location depending on v8 or 6 cylinder it appears

Screw covers?    O boy something else I didn't know.  Looks like a rubber cover like the ones on the tail light screws in the trunk.

In the following examples I used examples of fairly heavy applications of the sealant since they show up better that way and I highlighted the area I see covered or in some cases were it appears that there was sealant that fell off when rust developed behind it.

Take a look at this picture from my engine bay.  Notice the large areas of surface rust?  Do you think those areas are areas that use to have sealer but it rusted and fell off?  Seems to be a much larger area then you show so maybe not a good assumption on my part.

Looks like there may be more of that strip caulk around or under the top two bolts going through the firewall to hold the brake pedal bracket.  Is that typical as well or something to do with the fact that this car appears to have a tilt away steering column?

Did the sealer extend down to the emergency brake cable pass through?

What about the color of this sealant?  Ive been using 3M profesional undercoating (rattle can type)  for the wheel wells but it seems to be more of a dark brown then black.  Not sure if this would be suitable for this application.

[J_Speegle]

Thanks Jeff this helps a lot.  Just a few questions
Screw covers?    O boy something else I didn't know.  Looks like a rubber cover like the ones on the tail light screws in the trunk.

For this application they are the same gray hard plastic covers that are more often found in the trunk for the taillight studs. In the engine compartment they often got knocked off or fell off it appears

Take a look at this picture from my engine bay.  Notice the large areas of surface rust?  Do you think those areas are areas that use to have sealer but it rusted and fell off?  Seems to be a much larger area then you show so maybe not a good assumption on my part.

Think that the rust may have started under (between the sealant, what ever stuck to it and the firewall) but likely spread out from there, so I believe the area shown in the picture is greater than the original area sprayed

Looks like there may be more of that strip caulk around or under the top two bolts going through the firewall to hold the brake pedal bracket.  Is that typical as well or something to do with the fact that this car appears to have a tilt away steering column?

No tilt in the example (was/is a T5- fairly basic model). The application appears typical for a non- PB car at that plant, that year

Did the sealer extend down to the emergency brake cable pass through?

Depends on the worker and how much effort it was putting out that day but he should have gotten some spray over the area and the boot IMHO

What about the color of this sealant?  Ive been using 3M profesional undercoating (rattle can type)  for the wheel wells but it seems to be more of a dark brown then black.  Not sure if this would be suitable for this application.

Don't know for sure of the stuff used at NJ. Most are using black undercoating  though on  San Jose earlier cars (67 and before) I will try something else next car - but that does not apply here

[sparky65]

One more question.  The black plastic strips that hold the wires to the firewall.  My guess is they were not installed yet since the engine and trans wire harnesses they hold would not be in place.  The one for the heater wires could have been there but I doubt they would have installed these things at two different places along the line.

[J_Speegle]

One more question.  The black plastic strips that hold the wires to the firewall.  My guess is they were not installed yet since the engine and trans wire harnesses they hold would not be in place.  The one for the heater wires could have been there but I doubt they would have installed these things at two different places along the line.

Have not seen any evidence (overspray and the like) on the plastic wire retainers on this year this plant - that they were installed before the sealant. Now the heater was as well as the wiring attaching it so we do find evidence of sealer on the heater wire - Pretty common all years all plants (not sure of 71-72 ) on non- AC cars

[sparky65]

  Well I think I got way too much on.    Probably way too much on the master cylinder as well.  Do you think I should at least try to clean some of it off the master cylinder?

[J_Speegle]

Well I think I got way too much on.    Probably way too much on the master cylinder as well.  Do you think I should at least try to clean some of it off the master cylinder?

Yes the real challenge using todays products and applicators to reproduce the old stuff.

If it were mine, yes I would clean the master cyl, repaint if needed, then with the wand or applicator real close reapply it just around th ebase

[midlife]

My eye caught the wiring connectors coming out of the firewall.  Usually, the molded plugs are color-coded so that they match across the joint.  Your backup/NSS plug from the firewall needs a molded four-prong connector; you appear to be using an earlier (67?) backup/NSS harness that uses two separate 2-prong connectors.  Something isn't right here...

[sparky65]

My eye caught the wiring connectors coming out of the firewall.  Usually, the molded plugs are color-coded so that they match across the joint.  Your backup/NSS plug from the firewall needs a molded four-prong connector; you appear to be using an earlier (67?) backup/NSS harness that uses two separate 2-prong connectors.  Something isn't right here...

Interesting...  It is an early 67 car.   I have no reason to believe that either harness has been replaced but I dont know.   So should the dash side have 2prong plugs that match the wire going to the NSS?

[J_Speegle]

Noticed you missed one of the screw covers (should be two) (Purple arrow)





And a picture of the reverse/back up light plug from an Oct car - Notice how the plugs differ from your (Green arrow) plugs above