'38 Buick Special 40 - What does this do?

[johntsmith]

Just bought my '38 Buick Special touring and getting familiar with all the bells and whistles on the car.  This switch is broken and I have no idea what it was supposed to do. It was mounted on the bottom of the dash lip just to the left of the steering column. It's a rheostat of some kind.  The heater blower control is next to it.  So any ideas what it is and where I can get a replacement?

 

John 

[Mark Shaw]

It is not an original Buick part.  I suspect it may have been wired in series with the heater control to regulate the fan speed.

Just my $0.02...

[38Buick 80C]

8 minutes ago, Mark Shaw said:

It is not an original Buick part.  I suspect it may have been wired in series with the heater control to regulate the fan speed.

Just my $0.02...

 

Actually this most definitely an original Buick part it is the defroster motor fan switch. Hence why is right next to the Heater. Different motors for each so the knobs are different so you can feel the difference without looking. I did quite a bit of research on this and got an original one which I gave the knob to Skip Boyer to make reproductions of.  In one of the original Torque tube magazines there is a detailed article about heater and defroster switches for 37/38.

 

@Matthew Hinson perhaps you have a copy of that article handy to post.

[38Buick 80C]

oh and replacements come up on ebay as they were fairly generic, and you can get the correct knob from Skip Boyer as noted. an internet search for him / Boyer Restorations Hanover, PA can easily find his contact info.

[Jolly_John]

Yes, Brian. Definitely the reostat used by BUICK for a blower motor. I believe I have several NOS ones here. I wish I knew you had been looking for one, way back when.

 

You noted the heater and the defroster control knobs are different shaped, for easy recognition by feel while driving. On the very original 1939 BUICK I owned for years, the reostat knob shape posted by johntsmith was on the heater blower motor speed control (not the defroster). It was illuminated by a small bulb. The knob for the defroster blower was a little bigger in diameter, with straight sides and not a great deal of depth. It was maroon plastic, so I never doubted it was correct for the '39 model year. John

Edited July 7, 2021 by Jolly_John (see edit history)

[38Buick 80C]

5 minutes ago, Jolly_John said:

Yes, Brian. Definitely the reostat for a blower motor. I believe I have several NOS ones here. I wish I knew you had been looking for one, way back when.

 

You noted the heater and the defroster control knobs are different shaped, for easy recognition by feel while driving. On the very original 1939 BUICK I owned for years, the reostat knob shape posted by johntsmith was on the heater blower motor speed control (not the defroster). It was illuminated by a small bulb. The knob for the defroster blower was a little bigger in diameter, with straight sides and not a great deal of depth. It was maroon plastic, so I never doubted it was correct for the '39 model year. John

 

I got the one i found at a BCA National. For all I know I got it from you.

 

As for the defroster versus heater I may have it backwards from memory, but your descriptions sounds right in that you have the two types (and maroon being correct for '39)

[MCHinson]

Thanks for mentioning that Brian. I had never actually seen that information so I looked it up. 

In Volume 3, Issue 3, page 15 of the Torque Tube the following information appears:

 

[MCHinson]

Also, In Volume XIX, Issue 2, page 20 of the Torque Tube the following information appears:

 

Edited July 7, 2021 by MCHinson (see edit history)

[38Buick 80C]

11 hours ago, MCHinson said:

Also, In Volume XIX, Issue 2, page 20 of the Torque Tube the following information appears:

 

This is the one I was thinking about. Thanks.

[Mark Shaw]

23 hours ago, 38Buick 80C said:

Actually this most definitely an original Buick part

Brian, are you sure it is original equipment for a 38 Special or is it for a larger series Buick? 

My original Special does not have one.  

[MCHinson]

I think they all used that type of switch. I found the remains of those on my 1938 Century project and the 1938 Special body donor car. It is likely that almost all of them have been replaced over the years and many aftermarket switches have been substituted for originals on otherwise original cars. 

[38Buick 80C]

2 hours ago, Mark Shaw said:

Brian, are you sure it is original equipment for a 38 Special or is it for a larger series Buick? 

My original Special does not have one.  

Did your car have a defroster?

[Mark Shaw]

20 hours ago, 38Buick 80C said:

Did your car have a defroster?

No, my car only has a heater.   I would expect it may have been standard on the larger series Buicks.  So, perhaps the variable speed defroster was only offered as an option on the 38 Specials? 

[38Buick 80C]

2 hours ago, Mark Shaw said:

No, my car only has a heater.   I would expect it may have been standard on the larger series Buicks.  So, perhaps the variable speed defroster was only offered as an option on the 38 Specials? 

 

That would seem to make sense. 

 

Note my model 87 being a supposed SoCal car didn't have a heater and thus no defroster, so not all large series cars got them.

[Ben Bruce aka First Born]

From observation we know a LOT of pre-war cars were heater/defrost delete as evidenced by mutilated Data Plates.

  Those switches were used a lot in those days,  both factory and aftermarket'

 

  Ben

[37_Roadmaster_C]

My dads 37 Roadmaster has a heater, but no defroster and does not have that control.

[DonMicheletti]

Originally my '38 Roadmaster didnt have either a radio nor heater - it does now.

[Jim Nelson]

John,   I'm a 38-46s  Buick fan just south of you in Clearwater.      E-mail me at  'oldbuickjim@gmail.com'.   

[Jim Nelson]

John,  here is my '38-46s

[MCHinson]

Perhaps a bit off topic, but the old Torque Tube text about Heater switches mounting in the hole in the bottom of the dash on the left and Defroster switches mounting in a hold in the bottom of the dash on the right (passenger) side in Roadmasters sounded a bit odd to me. I am currently installing a new wiring harness in my 1937 Model 80C, and made an interesting discovery. There is only one large hole for switch mounting on the left side of the dash on my Roadmaster, but I discovered an identical factory hole located on the far right side of the bottom of the dash, just like the old Torque Tube article mentioned. While it seems odd, it looks like 1937 80 Series cars apparently had heater switches mounted on the left side of the dash, and defroster switches mounted on the right side of the dash.