TR6 76 TR6 Scuttle Vent

[sebarnes]

Hi all, I'm progressing on my dash pad and board replacement on my 76 TR6. Got the winshield replaced and mounted last weekend. My question is: My heater was not piped to the dash, it seems to be factory capped. The demister vents are hooked up. I plan on running new tubing for heater ducts and hooking them up. I have a working switch to install. Do I need to replace the rubber flap that is sealing the scuttle vent and replace it with a screen, or what? Not sure of what is mechanically correct here. Everything seems to indicate that this heater was not hooked up at the factory. Do I need to be aware of anything else before I start to cover up this phase of the project? Thank You All!

 

[BobbyD]

Hi Seabarnes.......I'm not sure what you're referring to when you say the heater isn't hooked up. TR6 heaters do not pump any hot air to the eyeball vents. Only outside cold air passes through them. The heater pumps air to the windshield via the demister hoses but the heat just falls out of that bottom flat on the heater box to get warm air into the cockpit.

Here's a great pictorial on overhauling your heater that may help

 

[M_Pied_Lourd]

I am wondering Bobby if the two pipes at the bulkhead have been capped off preventing any coolent from entering the heater core. If I were to decide not to use the heater, that is what I would do....take it right out of the system. Maybe we can get an answer if it is actually plumbed correctly first.

Cheers,
M. Pied Lourd

 

[Banjo]

All debate as the who unhooked your heater, or if it came that way, aside, yes. you'll need to remove any "block-off" that's been installed under the scuttle vent grille. A piece of screen would be an excellent idea to put in it's place.
That is the fresh air intake for the system.

 

[Gliderman8]

Bobby D.... Just a quick
Last week I installed the alternate heater valve that you show on your website... works great!
I also removed the detent ball so the heater cable moves freely and smoothy. Thanks again!!

 

[BobbyD]

Bobby D.... Just a quick
Last week I installed the alternate heater valve that you show on your website... works great!
I also removed the detent ball so the heater cable moves freely and smoothy. Thanks again!!

Not ot hijack this thread but..........where did you find the valve? They seem to be in short supply. AND..........how did you remove the detent ball? I've been afraid to take that apart.

 

[Gliderman8]

OK, after this reply, we can resume our normally scheduled thread :laugh:

I bought the valve from Kragens Auto last March, but since we were going summer I decided to wait and do the install now.
The Kragens I bought mine from was in California and they had to order it in for me. Since my wife and I were going to be in Calf. I just stopped and picked it up. Cost about $30.
As for the detent ball.... Remove the cabin heat cable. When you do you will notice a round spring clip that goes around the front of the cable housing. This spring clip holds the detent ball in place. Simply use a screw driver to pry the spring clip off the housing, and the ball will drop out of the hole. Let me know if you want a pic of the spring clip, I'm certain once you look at the heater cable you will see it. By the way, you can easily reinstall the ball if you want to.
Lastly, I used a short piece of clear vinyl tubing and pushed it onto the control arm to keep the cable from riding up. I thought the clear looked better than the black hose you show... just my opinion.

 

[sebarnes]

Hi, Coolant hoses are original factory plumbed into the heater core. My driver and passenger (what I assume are the hot air ducts) were never installed and the outlets on the heater are capped, affixed with rivets. I want to take off the caps and install what I am assuming are the hot air ducts. These ducts split, one end going through the dash, the other snakes around, attaches to the crash pad and looks to shoot air to the footwells. I have no pictures other than parts catalogs. If the heater only serves to produce heat to the demister ducts please let me know and I wont take it further. But if the heater also is supposed to shoot heat out the dash vents and into the footwells please let me know. Thank you again! Scott

 

[DNK]

No dash vents, just floor

 

[Gliderman8]

Heat only comes out from the very bottom of the heater to heat the cabin. It is the rectangular metal door that opens at the bottom of the heater box just above the transmission cover.

 

[BobbyD]

Hopefully you looked over Paul Rego's site that I previously posted. If so, this is the best picture I could find that shows the door flap on the bottom on the heater that opens to allow hot air into the cockpit. You can see the yellow foam on the inside of the flap. When the flap is closed it forces air into the connections right above the flap that go to the defroster.

Then navigate over to the TRF Green Book and on page 37 you'll find a great exploded diagram that shows everything BUT the flap! However you can see how the eyeball vent hoses connect to a point before the heater core, so all you get there is cold air that comes in from the scuttle.

If you can figure out a way to get both cold and hot air to the eyeball vents please share the secret with us..........we all wish it did that.

EDIT: Maybe this annotated picture that I just did will make it more clear as to why you don't get heat from the eyeball vents.

 

[sebarnes]

Hi BobbyD, Thank You and thank you to all for your input. The link and your pics have been a huge help in understanding whats really going on in that black box. I thought I was plumbing a heat system, now I know its just venting I'm moving around. My car does still confuse me, the heat dash rheostat was frozen and inoperable, and the rubber flap(looks like innertube rubber) that exists under the vent grill blocking all incoming air.

I am doing a dash replacement cause it badly needed it and also cause most of the small gauges dont work, along with some heater controls. I am working on the heater first and moving out from there. Was not planning to remove it, so if anyone has any testing suggestions, I'm very interested.

Thank You all again!

 

[Gliderman8]

The heater box is a PITA to get out, BUT if you're going to do a complete refurb, now is the time to do it (assuming you are removing the dash). I removed my heater core and flushed it out and made sure there were no leaks. Is it possible the previous owner had a leak and capped off the hoses?
You also might check the voltage regulator if the gauges are not working. It supplies +10V to the gauges. If it is not working you might consider replacing it with a more reliable solid state voltage regulator.

 

[DNK]

Take the core to a rad shop and have them clean and then pressure test it.

 

[sebarnes]

Morning all, You've got me to change my plans today and rather than ask I am committed to find out for my self the meaning of PITA. Heater box is going to be removed, and if I can figure out how to upload I will attach pics of the caps on the cold air outlets. Your help is tremendous, Thank You, Scott

 

[Gliderman8]

Not to worry... once you remove the heater box you will learn the true meaning of PITA

BobbyD... I sent you a PM

 

[sebarnes]

removal was not completed and I attained RPITA!