Under seat heater Qs: What years, and is new core available?

[brad54]

Can anyone tell me what years the Under Seat heaters were available in Buicks? I've got a '54 Special, and am a big fan of it.

I'm installing one under the seat in my '62 Chevy Suburban as well. The factory heater was designed to heat a pick-up cab, NOT a pick-up cab plus 10 feet of passenger compartment. What's in there now doesn't even take the chill off. (of course, carpet, weather stripping and a headliner would probably help.) I've got a new 3-speed switch from American Auto Wire, and a fresh 12-volt motor from the local Car Quest. I'd love to find a fresh heater core for it--anybody have any idea where I can find one?

I'm also writing a story about it for a magazine, and would like to include all the years these heaters were available. And, does anyone know what other brands had them? A friend had a '55 Pontiac with one.

Thanks,

-Brad

[Guest simplyconnected]

The very first one I ever saw was on a ('50's?) Studebaker. It was no more than a pipe that ran across the bench seat. It REALLY worked well with NO fan, and the water pump pushed the coolant (so no motor, either). That was the ONLY heater that car had.

Ford tractors used them inside each cab; a whole unit (core and 4-blade caged-fan together, with NO pump). It had a simple on-off switch for the fan. It got hot inside if left on all the time.

If you keep your pipe sizes big enough, you won't need a pump, but you will need a shut-off valve. Either a one-inch or 3/4" system would work just fine with a ball valve. Coolant carries a lot of heat with very little flow at 180*F. (Your home hot water heater is only ~120*F.)

I'm in Detroit, where we can't get heat soon enough in Winter. I'm going to plumb my bench seat with TWO copper pipes, (just to get the surface area). Any air motion under the front seat will spread heat well because of convection. Another help is to get hot coolant from the back of your right head (on a V-8). That will bring heat ASAP.

[Guest ewing]

My 47 Buick has an underseat heater, Its a small rad like core with water fed from the coolant system, under the seat ( passenger) side and a return hose back to the engine coolant system.

I'd guess they were in earlier BUicks too as the car was essentially the same in 46. I don't know about prewar, except there was no under seat heater in my 38. In the 38 the heater box was on the inside , firewall mounted, in front, on the passenger side.

My 58 Buick as under seat heater that was a copper tube, finned under the driver side and again finned under the passenger side to throw heat ( but no fan, just passive heat radiance).

There are pictures of the 58 underseat heaters in smartin's post on me and my buicks, with his 58 Limited project car

[Matt Harwood]

I have one in my '41, which was an option (they were standard on the open cars, I believe). It's a ring-shaped radiator in a housing with vents out the front and back and the fan in the center of the ring:

Here's the [very gunky] heater core:

I don't know if reproductions are available, but you could probably source one from a parts car. I bet most GM cars of the 40s had something similar, either standard or as an option.

[brad54]

Thanks guys.

Anyone else have anything at all to ad?

the one in my '54 looks very similar to the one Matt posted. They put it under the driver's side, and there is a screen over the fan (1/4-inch square metal "hardware store" screen).

Same looking core.

All the ones I've seen seem to be havens for mice. I'd bet if you look close at the gunk in those fins, you'd find hair and mouse raisins. The one in my low-mileage '54 Special had lots of droppings, and the one I got off ebay has several, and lots of hair. There is a bunch of green corrosion, and I'm betting it's from mouse wizz.

I'm going to blow the fins out with the air compressor, then soak the coil in lemon juice of vinegar...some sort of a mile acid to clean the copper. Then use my Eastwood radiator fin pliers to straighten all the fins and have it pressure tested at a shop.

I ordered a Y-junction and a manual shut-off valve for under the hood, so I can turn off the water in the summer. No need to have hot water flowing through the cabin in a Georgia August.

-Brad

[Guest simplyconnected]

Brad, you can put your shutoff valve anywhere in the circuit, like conveniently under your seat. When coolant stops flowing, so does heat. There may be times when you will want to shut it half-way off, after your cabin warms up.

What size are the inlet/outlet tubes on those heater cores? Are they 5/8"? 3/4"?

Dave

[Guest imported_JPIndusi]

On both 1948 and 1953 (Special with straight eight) they use 5/8 inch heater hose. I think they went to 3/4 inch on the later V-8 cars.

Joe, BCA 33493

[Guest imported_MrEarl]

You're right Joe, 46-55 were 5/8 and 56 went to 3/4.

Actually the under-seat heater is typically referred to as the "heater" and the unit in the firewall is the defroster.

[brad54]

It has an electric motor...I bought a new motor, and a 3-position switch so I can regulate the heat nicely.

I want to cut off the water in the summer--no sense running hot water under my butt!

-Brad

[old-tank]

Brad

You don't need a cut for the under the seat heater. Water flow is stopped by the same control on the firewall that serves the front heater.

Water flow: left water crossover manifold==>under seat heater==>front heater==>heater control valve==> bottom of radiator.

Willie

[brad54]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: old-tank</div><div class="ubbcode-body">Brad

You don't need a cut for the under the seat heater. Water flow is stopped by the same control on the firewall that serves the front heater.

Water flow: left water crossover manifold==>under seat heater==>front heater==>heater control valve==> bottom of radiator.

Willie </div></div>

Except I'm putting it in a '62 Suburban. The Chevy feeds the water off a port on the water cross on the intake manifold and another off the water pump itself.

The standard chevy truck heater doesn't have any water cut-out, so there's always hot water flowing through the heater core under the dash. I don't want the water flowing under the seat, too. It's warm enough in July in Atlanta!

I plan on restoring a Deluxe heater, and need to figure out if that one cuts off the water with one of the actuation levers, or if it's always "hot" too.

-Brad

[Fred Rawling]

I have a under seat heater from a 1950 Buick that I would like to sell for $35.00 with a core that looks good and holds water without leaking and a fan motor that works.

E-mail me if you are interested and I will give you measurements and pictures.

Fred

[Guest Skip 52 Rag]

Hi Fred: I'm interested! Please let me know if you still have it and let me know how to pay you if you do! I've been looking for one for a while now.

Skip

[Underseat heater]

I have one in my 41 Chevy I would sell for $35.00 I have not found a motor yet, I am still removing it [got side tracked ]

[Steanson]

Saw a picture of a 49 Cadillac with the underseat heater on both sides.

Stean

[sg5054]

I have 53 Super with one. How do I know? Because it bled out onto the passenger carpet over the winter.......

[BS1946Caddy]

As early as 1946 Cadillac had them on both driver and passenger sides, possibly earlier so you should be able to find them.

Now for my question 😁

I am converting my 46 to 12v and I am wondering does anyone know what I need to do to make the fans work independently from the heaters? I am going to add AC and think it would be nice to have those fans on to help circulate the air.

I am thinking about installing a High Med Low switch... should I also reduce it to 6v to not burn up the motors? 

Thanks!

B

[Ben Bruce aka First Born]

11 minutes ago, BS1946Caddy said:

As early as 1946 Cadillac had them on both driver and passenger sides, possibly earlier so you should be able to find them.

Now for my question 😁

I am converting my 46 to 12v and I am wondering does anyone know what I need to do to make the fans work independently from the heaters? I am going to add AC and think it would be nice to have those fans on to help circulate the air.

I am thinking about installing a High Med Low switch... should I also reduce it to 6v to not burn up the motors? 

Thanks!

B

 

 Just block the coolant to the heater.

 

   My understanding the 12V will only make the motor run faster.

 

  Ben