TR2/3/3A TR3 Heater

Gentlemen:

I have a TR3B. I bought it a year ago but had little opportunity to drive it due to my work. I did drive it in the summer before putting it in storage. I returned to the US about a month ago and drove the car on two long distance trips in the ice cold. The car has a heater, including the hosing and water tap. However, it is missing a number of things, including any venting. I also checked the Moss catalog for the heater parts. I know for sure mine does not have an electrical switch and the exhaust vents for the demister.

I did open the hot water tap before taking my trip, but that did not produce any heat. Now, here come the questions:

- Where does the electric switch for the heater normally go?
- Does the heater have a built-in fan? If not, is there a fan assembly?
- Should it be able to function w/o an electric switch? If yes, is this an indication that my heater is not functioning?

Thanks,

Mike Pennell

Hi Mike.

Rheostat (switch) for the heater blower should be at the far left of the panel. Fan is under the dash where the heater coil is located.

Opening the valve at the engine should allow water to move through the system and the coil, unless the pipes are clogged and blocked.

But even with a mighty fan blowing in that coil, you'll only feel "gerbil breath" coming out, even if you've sealed all the gaps in the firewall, top, and doors.

Tom

What Tom said. Pathetic would be a compliment for the TR3 heater.

The fan, radiator, vent flaps, and demister are all in the same assembly. If the fan turns, you get a little heat. With no fan, you get no heat. The heater could have been installed by the dealership, so the rheostat switch could be anywhere.




This pic is the dash to the left of the tach/speedo. The knob on the left is the dealer installed windscreen washer push button, and the large black knob is the heater rheostat. Again, the heater could have been dealer installed, so the rheostat could be anywhere in the dash...

Just for clarity, the fan motor is in the center of the circular heater coils; the blades are inside the lower housing. The heater is a recirculating type; there is no external air intake for it, so it produces essentially no heat without the fan running. So, hooking up a switch may be all that is required to get at least some heat. Although Smiths optimistically supplied a rheostat so the speed could be adjusted, a simple toggle switch will do fine. Full speed is never enough heat, unless you don't need heat at all.

Years ago, when I lived in a cooler climate, I put some effort into increasing the air flow, by rewinding the motor to run faster (and draw more power) and tweaking the fan blades for the maximum pitch allowed in the tiny space. It did help, but not enough to make any real improvement in comfort. I got to the point where the heater would almost burn my right leg while the rest of the car was still near freezing and gave up. I even experimented with adding a spacer to make room for an even more aggressive fan, but it proved to be simpler and more effective to move to a warmer climate

Thanks, guys. It sounds like a pointless effort - from the standpoint of producing heat.

I took my car from Washington DC to Nashville, TN. The first day the temperature was 10 degrees outside and about 15 degrees inside! I returned the car to DC about 2 weeks later when the temperature got to a balmy 35 degrees. Either way it was a brutal experience that I would recommend to anyone. I guess the moral of the story is to limit my driving to days when the temperature is over 65 degrees.

Mike Pennell

Dressing for the occasion can help a lot, too. With my heavy leather jacket, leather cap and leather driving gloves, I'm still pretty comfortable down to 40F or so even without a top. (Leather blocks the wind better than almost anything else you can buy. 60 mph will go right through any kind of woven cloth.)

Well, with decent side screens, seals for the windscreen to scuttle, and hood, and rags stuck in all the other gaps...you get a good bit of heat from the tunnel and firewall. With a fully operational heater you are not comfortable on a long trip, but you are not in danger of severe frostbite!?!

Revington sells upgraded heaters for 3's and 4's https://www.revingtontr.com/shop/pr...D0ETK0WLAHDJQB&CarType=TR3&ProductID=RTR1395K

Good ole Bob Shaller has a solution for the anemic TR3 heater in his "More BS about TR's" booklet. You install a Spitfire heater in place of the stock unit. I did this and it's a big improvement in heater output.

More BS about TR's I have heard of that booklet, is it available?

I won' even attempt to argue that the TR3 is comfortable in any weather that is not basically clear and between 68 and 72 degrees F. However, I drove mine winter and summer in northern New England for ten years never once was I hospitalized for frostbite. I still have the Amco ski rack. The stock heater kept me alive in temperatures down to about -20 F. Below that the car usually didn't start. (I once prematurely ended a promising relationship by forgetting to open the passenger heater door).
The defrost kept a spot on the windshield clear enough to see ahead, even in a snowstorm, if augmented with a swipe with a gloved hand occasionally. When things warmed up to 60ish, that tap had to be closed even with the blower off, if the top and curtains were up and in place, or it would get unbearably warm.
I thought this was all part of the Triumph experience. Have we all become wimps?
Tom

I drove this car, dead of winter from Portland, OR. to Dexter, MI. with my wife and 2 year old son in 1973. I installed an auxiliary heater from a 1950 Ford pick up (looked a lot like ours, but much, much better) on the passenger side and tee'd it into the heater hoses under the bonnet. It was at least 10 degrees warmer on her side of the car. I could actually feel the difference by moving my right hand over to her side. She left me 6 years and several TR3s later. Go figure.

I think Randal has a link to the book online from the last time mentioned it but I don't think its available anymore in a print copy?

The easiest fix I found was to move to Palm Springs.

I believe TRF offers reprints, or there is a PDF you can download from
https://drive.google.com/file/d/0B2...MmJmLWFiZGItNTI5ZjI3N2NjZTIy/view?usp=sharing

Thanks Randall, appreciate it.

TRF P/N is RFP128, $16.95

Here's a long story, because I am bored and the forum seems to be dead this morning.

My first car was an old Camaro. Being the typical "gearhead", I was always trying to do mods to help performance and such. So, one day I read in Motor Trend how much power went into spinning the radiator cooling fan...and how above 30 mph the fan slowed the airflow more than it helped. I removed the fan and crafted this beautiful little sheet-metal duct to route the air from the back of the radiator to the bottom of the car, where it should exit. If what I read was true, it should add some power and maybe a bit of top end!

Well, it was a dismal failure. I learned that while the car would cool fine on the road above 20 MPH if I just removed the fan belt, when I ducted the hot air downward the engine overheated at any speed under 60 mph. In the end I realized you can't fight the laws of physics. Hot air wants to rise. Trying to duct hot air lower just does not work.

The first look at my TR3 heater brought the Camaro lesson back to mind. Smiths tried to heat the air and then blow it downward. Hot air wants to rise, not sink, so this little heater was doomed from the minute they chose the downflow configuration.

Now, the natural question is...would it work better if we reversed the fan direction? Of course the defroster would be useless, but it may transfer a lot more BTU's into the cabin...

I think " ... little heater was doomed ..." when it was installed in an open top, un-insulated, air-gap strewn car!

I doubt reversing the air movement direction would change a thing; you still have the same BTUs trying to heat a cabin with way too much cold air coming in.

Edit: maybe your Camaro overheated because the engine wasn't getting any cooler air moving over it?

Just my two shekels.
Tom

I live in the Seattle area and there is cold, and there is wet and cold. Here in the winter we are wet and cold. I worked for years on the pipe line pumping stations with guys from all over country plus outside all the time and their complaint was this place is cold in your “bones”. A good clean running tr3 heater will do the job. I have had many.