Why do I have two heater cores in my 1965?

[daner]

Probably a silly question, but cleaning out the front of my 1965 (titled as a 1966), I noticed that it has a heater core in the center unit and a heater core on the firewall mounted unit under the glovebox. Never noticed a truck before with two heater cores...
Anyone know why there two? Is this stock?

 

[Living in the Past]

Two heaters in the front is not stock. My guess the one under the glovebox was installed as a aftermarket years ago and then later someone was working on installing the optional in 65 factory heater. Is there a blower in the engine compartment opposite the glovebox? How about the fresh air vent outside of the blower? If those are there then blower or heater coil failed and aftermarket was installed for cost reason.

 

[daner]

Thinking about your comments has given me a theory based on your theory...: My guess-and it is just a guess as I seem to be missing quite a few pieces of the stock unit assembly, is that the heater core unit mounted in front of the blower on the firewall is not stock. it likely was an ad-hoc replacement for the original unit that mounts in the center (pics below). If this theory is correct, the cute little stock unit I just spent a few hours sanding and painting, will leak like a sieve....

 

[whitey45]

Factory heater with the ultra cool 45 degree intake vent!

 

[pardion]

Curious what is stamped on the brass tag added to your ID plate. T-65, or T-66? As T-67 were aluminum.

 

[Living in the Past]

Factory heater with the ultra cool 45 degree intake vent!

Though they were so cool I picked up a couple of them even though my 65 FJ45LP-B was a non heater model. Picked a couple of the early heaters as well.

Curious what is stamped on the brass tag added to your ID plate. T-65, or T-66? As T-67 were aluminum.

More curious what power plant is under the hood. That's not a Toyota valve cover.

 

[whitey45]

Looks like an om617 Mercedes 5 cylinder

 

[daner]

The brass tag says "66". The VIN indicates it was a mid 1965, so towards the end of the Corrugated top/diagonal heater era.

The motor is an OM617, I purchased the truck without a motor, trans etc., so am swapping in the 5 cylinder with a Toyota 5-speed. There is a build thread in the diesel section, thanks for the input and comments

 

[Living in the Past]

Thinking about your comments has given me a theory based on your theory...: My guess-and it is just a guess as I seem to be missing quite a few pieces of the stock unit assembly, is that the heater core unit mounted in front of the blower on the firewall is not stock. it likely was an ad-hoc replacement for the original unit that mounts in the center (pics below). If this theory is correct, the cute little stock unit I just spent a few hours sanding and painting, will leak like a sieve....


View attachment 1507210
View attachment 1507217



View attachment 1507204

I believe the heater core from the 68-73 models will work in earlier factory heater. The plastic duct and rubber collar are the same as well. Hardest part to find is the rubber rubber elbows for defrost hoses.

 

[daner]

Good to know, thanks

 

[SteveH]

I used a '77 heater core in a '65 heater housing. Very slightly smaller in a few dimensions - make up the difference with some foam strips. I also Muriatic-acid-cleaned the '77 core first, and my '65 heater was nice at toasty warm when I was finished.

 

[daner]

Thanks-surprisingly it hasn't leaked. yet.

epic fail may be waiting until I leave pavement....