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TR2/3/3A TR3A Heater Output

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T

TR3AD

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My heater seems to have two modes: "Off" and "Feeble". The heater core stays nice and warm, but the fan--even at top speed--is weak, leaving me in the cold. Is this how they originally came from the factory? Is there a simple way to improve the output from the heater? I'm f-f-f-freezing.
 
I wouldn't call it simple, but it is possible to rewind the motor armature with fewer turns of heavier wire and get a bit more air out of it. I did it once, but didn't feel the results were worth the effort. That strange fan just doesn't work so well, and there isn't room for a fan with more pitch. I also tried extending the housing a bit for a larger fan, which also helped some but likewise not very much.

Obviously before taking those steps, be sure the bearings turn freely; the motor is getting a full 12v under load, and the brushes are in good shape. Just soaking the bearings in oil (with the motor disassembled) for a few days made probably the largest single improvement I managed.

For the ultimate, a different heater assembly is called for. Supposedly the flat heater assy from an early Spitfire fits pretty good behind a TR3 dash, but I haven't tried it. Bought a heavy leather jacket, hat & gloves instead /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
The best way to improve the creature comforts while driving a TR3 in colder weather is to dress warmer.
 
Hamster breath.... The only heater in a vehicle I've found to be even mor ineffective that the TR3 is the one in my CJ5.
Eventually it thinks about melting the ice in the windshield.
Gotta dress like your going for a snowmobile ride..... Jeesh.
 
Well, if you're freezing in California, maybe there's no hope for the TR3 heater warming you up. /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif

The TR3 heater fan is not very good but mine was a little slow until I cleaned the ground connection real well. It was a little dirty (very little) and caused enough resistance to keep the fan from spinning freely. Also try replacing you heater rheostat with a simple switch as a test.

It's not very warm here in Maine butt (sp. intended) that is the reason I installed seat heaters for those late fall drives. Right now, we've already had 21" of snow here and the next one is going to be a doozy! Our TR3A is cozy in my shop waiting it's new wiring harness.

Good luck, try the ground wire/new switch trick and wear warmer clothes if you get chilled.
 
If you REALLY want more heat, get a Wedge. /bcforum/images/%%GRAEMLIN_URL%%/jester.gif

Even with the best heater, you're gonna need to dress more warmly. Suit up and enjoy!
 
I don't know, I can feel the heat on my feet at speed with my rebuilt unit (one flap open) with the tonneau on at 60+mph. Doesn't seem anemic to me (for it's age and design).
 
When I was restoring my 1958 TR3A from 1987 to 1990, I knew that the heater core had been leaking. I couldn't solder the leak. A TR friend in Wiltshire, UK (Thanks Jon) gave me one that he said didn't leak. There were two reasons that it didn't leak. Firstly, there were no leaks in the core and 2nd, it was so clogged with rust and gunk that there was no flow. I filled it with water at low flow (no pressure) from my garden hose and then sloshed it up and down. Then rust, etc, started to come out one end. So I did the other end. Same thing. Then about about 100 fills, slosh and drain at each end, I got the water to gently flow from the inlet to the outlet. Then I continued to shosh it till the water was clear. Yours may be blocked like this one was.

It has been in my TR since 1990 (97,000 miles) and while my dear wife says she gets cold, I think that it's performing about like it did when the car was new.

If you think about all the stories of the rust etc, that blocks the drain tap on the block above the starter and all around cylinder #4, why wouldn't the heater core also be filled with crud since it is fed from the same area.
 
PeterK said:
Well, if you're freezing in California, maybe there's no hope for the TR3 heater warming you up. /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif
Click to expand...

I know "freezing" is relative, especially when comparing California weather to Maine at this time of year. It's still sunny, yet cool here in SoCal (Highs in the mid-60s). Perfect for tooling around during the day, but dropping into the early 40s at night. That's when it gets brisk.

I'll try cleaning the connection and make sure the fan is performing as well as it can. Then I'll get a transfusion with some thicker blood.
 
I have to say that with the tonneau on and the heater on my feet are toastie. I suspect that you need to flush the heater matrix and have a look at the wiring to the fan. Take it all apart and give it a good clean.
My heater is also very effective at cooling the engine when I am stuck in traffic in the summer.
 
NickMorgan said:
My heater is also very effective at cooling the engine when I am stuck in traffic in the summer.
Click to expand...

Of course, you have to get out of the car, raise the bonnet, and then open the heater valve! Then do it again and close the valve when the traffic starts moving. /bcforum/images/%%GRAEMLIN_URL%%/hammer.gif

I'm installing an electric radiator fan. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
I never close the valve off. I just use the doors on the heater and the fan to control when it puts out any heat.
 
WIMPS!! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
My TR3 doesn't even have a heater. I use a leather jacket and gloves. My wife keeps a blanket in the car in the winter, when she gets cold she throws it over the transmission tunnel and her legs.
One nice thing about not having a heater is in the summer you can open the vent and that blows enough air into the footwell to keep it from getting hot. We refer to that as the 'Air Conditioner'.
Generally when it's less than 50 I drive the Porsche.
 
When I first got my TR3, it was February and 7 degrees outside and I was driving the car (no salt on the roads). The heater was nice for the fingers.
I'm still driving with the top down at 50. WIMP!
 
Good one! I deserved that.
I have to have a reason to drive the Porsche so I came up with the 50/50 rule. If it's more than a 50% chance of rain or less than 50 degrees I drive the Porsche to work. A 50% chance of rain here means that there is a 100% chance that it will rain on me somewhere on the way home at 3:30 in the afternoon. Plus it is less than 50 only about 10 days a year here and the rule only applies to work days.
 
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