Topic: 1970 Firewall Blower Motor Shield Question

[67shelby]

I'm working on a 1970 SCJ Mach 1 built in Dearborn on October 11, 1969.  I've owned the car since 1980.  My question is about the blower motor shield, when I disassembled the car, there was not one present.  I don't ever recall one being on the car as far as I can remember.  I have acquired one and when I was getting ready to install it, I saw examples on cobrajet.org (https://www.428cobrajet.org/id-firewall-shield) I have the one on the left.  But on the second picture down it shows that there are two screws that hold the bracket in place as well as two of the nuts from the blower motor.  I have attached a picture of my firewall before metal work was started and as you can see, there are two dimples (circled) where the two screws would be, but as you can see, they were not ever used.  I've seen some posts from Bob Gaines saying he'd never seen one without a shield, but did all cars get a shield and not have the two screws to hold them in place? 

[Bob Gaines]

I'm working on a 1970 SCJ Mach 1 built in Dearborn on October 11, 1969.  I've owned the car since 1980.  My question is about the blower motor shield, when I disassembled the car, there was not one present.  I don't ever recall one being on the car as far as I can remember.  I have acquired one and when I was getting ready to install it, I saw examples on cobrajet.org (https://www.428cobrajet.org/id-firewall-shield) I have the one on the left.  But on the second picture down it shows that there are two screws that hold the bracket in place as well as two of the nuts from the blower motor.  I have attached a picture of my firewall before metal work was started and as you can see, there are two dimples (circled) where the two screws would be, but as you can see, they were not ever used.  I've seen some posts from Bob Gaines saying he'd never seen one without a shield, but did all cars get a shield and not have the two screws to hold them in place?

The shields were put on at Ford so it is a fact that they were as a matter of Ford procedure on all BB car when the engine was installed . The engineering documents say after engine was installed that they were supposed to be taken off but what with the difficulty to do so with a big engine in a small engine bay the fact that they didn't hurt anything being left in place most of them were left in place. That is not to say some of them were taken off at the factory but it is more typical to see them still in place then not. yes i have always seen the shield still in place on the many survivor type GT500's I have seen . But that is just me. Now with all that out of the way do you have the 67/68 shield style or the 69/70 shield style? they both will work but only the correct year style will line up with the hole patterns because the year styles are slightly different. It will look silly to a informed eye if you use the incorrect one so be sure it is correct. I have posted a picture to verify. 69/70 on left 68/67 on right compare hole patterns. the long finger was for a non air car and the finger was cut off for a A/C equipped car but in real world usage I have  seen both used in ether A/C non  A/C application 

[67shelby]

Bob, I have the short one on the left.  The holes line up with the dimples, but as you can see in the picture I attached, the two holes that are not part of the heater motor were not drilled.  So if I put it on, and only use the two bolts on the blower motor without the screws, is that correct? 

[67shelby]

I attached a picture from Cobrajet.org, showing the two screws.

[Bob Gaines]

I attached a picture from Cobrajet.org, showing the two screws.

From the picture angle your sample looks like a 67/68 style shield it is hard for me to tell from the angle. You can see what i mean if you compare the holes to the examples i posted. The CJ site doesn't go into detail about the different year versions. There are a number of possible scenarios why your firewall doesn't have the screw holes in it . Some terrible to think about and others not so much. It is hard to say with limited info from my end.  For instance I have seen the 69/70 shield held on by nuts put on the studs or stud from the heater motor. YOU have to make a choice to put it on or not . So you understand this discussion better,the debate is NOT whether it was on there originally (for a BB), the debate is whether it was taken OFF or not after the engine was installed. It is your car to do with the way you want . If you don't care that others will think that the shield is missing when they look there (being a BB)then don't put one on. If you do care then do put one on . If you decide to put one on then I would put it on the way it typically was installed since you don't have proof (picture before restoration) that it was done another way (Like with the nuts)if someone is skeptical. Some people like drama . I would myself would rather avoid the drama that a out of the ordinary detail brings up but that is just me. In the end it is your choice. I hope this helps. 

[67shelby]

Yes and no.  But you really haven't answered my question.  I understand your position of they were on the car. The question really is have you seen cars with the shield and not have the two mounting screws. My feeling is that I'll probably lose the same amount of points for the bracket being gone than if the two screws are missing.  I do have definitive proof that this car did not have the screws in that the firewall dimples are still in tact. I'm going to mount it on the two nuts on the blower and leave off the screws for now. I'd like to see some more evidence that every car had screws before I drill holes in an original firewall.

[rockhouse66]

I wouldn't drill holes where you know there weren't any originally.  Maybe that's just me 

[WT8095]

Yes and no.  But you really haven't answered my question.  I understand your position of they were on the car. The question really is have you seen cars with the shield and not have the two mounting screws. My feeling is that I'll probably lose the same amount of points for the bracket being gone than if the two screws are missing.  I do have definitive proof that this car did not have the screws in that the firewall dimples are still in tact. I'm going to mount it on the two nuts on the blower and leave off the screws for now. I'd like to see some more evidence that every car had screws before I drill holes in an original firewall.

Bob did answer your question:

For instance I have seen the 69/70 shield held on by nuts put on the studs or stud from the heater motor.

My opinion: don't drill the holes, like Jim said. You have photographic evidence that they were not drilled originally (for whatever reason). It's hard to undrill them if you change your mind.

[Bob Gaines]

Yes and no.  But you really haven't answered my question.  I understand your position of they were on the car. The question really is have you seen cars with the shield and not have the two mounting screws. My feeling is that I'll probably lose the same amount of points for the bracket being gone than if the two screws are missing.  I do have definitive proof that this car did not have the screws in that the firewall dimples are still in tact. I'm going to mount it on the two nuts on the blower and leave off the screws for now. I'd like to see some more evidence that every car had screws before I drill holes in an original firewall.

You must have missed the part of my post where I wrote " There are a number of possible scenarios why your firewall doesn't have the screw holes in it . Some terrible to think about and others not so much. It is hard to say with limited info from my end.  For instance I have seen the 69/70 shield held on by nuts put on the studs or stud from the heater motor." By the way that example is one of the least terrible explanations that the issue brings up  . It is ultimately up to you on how to proceed. Your choice . Just be prepared to back up choices with photo documentation (at least the firewall) to prove to others your choice every single time the question comes up other wise you will come off looking like any over enthusiast doing something non original on their car with a "story" and trying to justify it with no proof. It is important to note that if you don't care what people think then disregard my previous statement. That previous sentence is what I referred to as "drama" over a detail in my previous post.  Best of luck on what ever you decide.

[67shelby]

Sorry to beat what you might think is a dead horse, but....  Went out this morning to look at it again thinking I could attach it without screws.  It isn't even possible, unless the brackets were held on with only one nut. 

This is a non-air car (drag pack).  In looking at the Osbourne production manuals, the part is listed on the pages with air conditioning and only one page that shows what might be non air cars which was marked as CANCELLED.  It seems to me that it is plausible that Ford used the shield on AC cars to protect the expansion valves, but may have discontinued the use of the shield on non-air cars which only had the fan motor to protect.  I will document the fact that there were no holes in the firewall and therefore the bracket could not have been mounted permanently.

[Bob Gaines]

Sorry to beat what you might think is a dead horse, but....  Went out this morning to look at it again thinking I could attach it without screws.  It isn't even possible, unless the brackets were held on with only one nut. 

This is a non-air car (drag pack).  In looking at the Osbourne production manuals, the part is listed on the pages with air conditioning and only one page that shows what might be non air cars which was marked as CANCELLED.  It seems to me that it is plausible that Ford used the shield on AC cars to protect the expansion valves, but may have discontinued the use of the shield on non-air cars which only had the fan motor to protect.  I will document the fact that there were no holes in the firewall and therefore the bracket could not have been mounted permanently.

First off you have a shield that has the finger cut off which was technically for a A/C car. Not that it matters a lot because I have seen them used indiscriminate in practical use but if considering using one that was not with the car it makes most sense to use the type that was supposed to used for the application (with finger attached) but that is just what i would do if my car. Next again you must have missed reading in my post "For instance I have seen the 69/70 shield held on by nuts put on the studs or stud from the heater motor."  The other stud when used had the bracket pushed up against the firewall for the nut to engage. I went into my shop and put a correct shield up to a 69 heater motor firewall and the second nut will engage.  My expertise is with 65-70 Shelby'.  A 70 Shelby is a left over 69 . With that said a 70 BB car has a large number of differences then a 69 which I have not studied the 70 Mustang much and this maybe one of the differences . Ed Meyer is a expert on 70 CJ car differences and my go to guy for information on them. I will ask him his perspective on this issue and post back if he dosn't post in the mean time.

[Vcode]

I wouldn't drill holes where you know there weren't any originally.  Maybe that's just me 

+1 I'm with Jim on that...

[Bob Gaines]

I would also mention that for a historic look the shield if left installed should have sound deadner/sealer  on it as it was on the firewall when that was applied . By the same token if left OFF there should be evidence (witness line )of the shield being un installed. I don't have a copy of the 70 electrical assembly manual but if it says cancelled indicating the shield was not used on a 70 non air BB. The sealer witness line in that case would not be appropriate. 

[7Lscjracer]

I'm with the leave the firewall holes undrilled camp.
Finding the screws could be a problem anyway.
The AMK kit doesn't include what survivor car screws look like.
Phillips modified truss from what I've seen, guessing #8, length and drillex or not I don't know.
Perhaps there was a parts shortage so the shield wasn't installed.
Perhaps they were short the screws and just attached it with one nut.
Perhaps the line worker couldn't be bothered to attach the shield at all, or couldn't be bothered to drill in the screws after attaching the shield with only the nut.
What about the 428 registry?
Poll other cars around your build date to see if they're the same situation?
Comes down to whether you want to restore your car to spec, or restore it to the way it came off the line.
I'll give you an example of my San Jose car, the kick panels have a screw put through one proper hole while the other is left empty.
The second screw is drilled thru the panel further down from the second hole in a convenient spot.
A case of the line worker saying I'm not reaching all the way up there.
I would expect other cars around my build date to be the same, and I'm not changing it.
I'm on the as built side of things as opposed to spec side of things.

I'm not reviewing my post because 3 other replies happened while I was typing.

[rockhouse66]

I had forgotten this detail when I posted about leaving it undrilled, but apparently I followed my own advice on my '69 San Jose car.  The shield was missing but the witness lines that Bob mentioned are very evident.  The screw holes were never drilled.  The heater motor stud that you see on the left in the picture had no nut on it at all.  I was able to mount the shield with just the two nuts.  I later sprayed some sound deadener on the new nut you see in the lower picture to make it look more original.