TR2/3/3A TR3A heater

[NutmegCT]

Has anyone pulled and repaired/replaced a TR3A heater? I've seen lots of TR6 heater info here, but so far haven't found anything on a TR3A. Mine is cut out of the loop (hoses bypass the heater core).

Is this a total PITA which only a very patient and very expensive British car mechanic can handle? I've done it on an MGB and swore I'd never try it again.

As the core is under the dash it must be a "challenging adventure" to pull, flush, check for leaks, etc. Maybe there's a step-by-step webpage around?

Thanks.
Tom

 

[martx-5]

Just grab a flashlight and look under there. The TR3 heater core is very accessible, and very easy to yank out. It's screwed onto a couple of brackets under there. There are two ducts that go to the de-mister (defroster) outlets that pull right out. The two hoses upclamp from the bulkhead fittings on each side of the heater core, or you can disconnect them at the heater. There are two wires to disconnect. The hot one from the dash rheostat and a ground wire that should be attached to one of the brackets holding the heater core on. You may have to unscrew the bracket for the choke cable so you can move it a bit to the side to make it easier to get the core out. I've also taken the cores out by removing the two brackets with the core attached. I don't remember which way was easier.

After you get it out, you'll have to bring it to a radiator repair shop for repair. I don't think they will be able to recore it, as it is circular. If it can't be repaired, they show up on e-bay all the time. It's not an item that I have seen fail very often, so who knows why yours is out of the loop. Maybe the shut off valve under the hood is no good or missing, so the previous owner just decided to bypass it so there wouldn't be any heat in the car during the summer.

 

[PeterK]

Art,

I R&R'd our 3A heater at home except for the core itself. My core needed soldering on the inside of the core (was dripping slightly.) The radiator guy called it "delicate item to repair." After 48 years, they start to disintegrate just due to age. Rated only at 4PSI - this is important to tell your radiator shop to prevent blowing the sides out the of tubes with too much pressure. I think they'll take up to 7PSI, which is better for cooling for the radiator.

Blast and refinish in black wrinkle as original. I found putting the demister hoses back on to be a royal PITA. But otherwise an easy job.

BTW, new cores are around $400 when you can find them. I bought a nice used core on ebay for a spare for $50.

 

[Brosky]

Tom,

I've never done one, but I've heard you can have them out and back in before a TR6 unit is halfway out.

Yours may be able to be flushed, in case it's full of crap, but get a good radiator shop to do it. Check the valve as recommended above.

I don't know where you are in CT, but there is a shop in Cranston, RI, that specializes in old stuff and classic cars that could probably help you out.

Airport Auto Radiator
598 Atwood Ave
Cranston, RI 02920
(401) 942-7868

Good luck,

 

[Twosheds]

Isn't there also a bolt that goes through the firewall and is held by a nut just above the battery? It also holds a clamp for the brake line that goes across the top of the firewall.

Going from memory here; could very well be wrong!

 

[mrv8q]

Tom, not too nasty of a job, it's all pretty self-evident. After I took mine out and hose flushed it, I took it to a couple radiator places I've used in the past. Neither would touch it, "too delicate" each said. That said, I gave it a good flush, and it's relatively warm; they will never equate to a modern heater.

It's obviously a good time to renew your under-dash hoses and bulkhead couplers. Mine were rusted shut after 20+ years. I'm going to brave the 70+ degrees tomorrow, and motor in my 3A to my local club breakfast; first time in 6 weeks. A recalcitrant TR6 will do that to you!

Have fun w/ the heater; you have a chance to eye the under-dash wiring as well!

 

[rlwhitetr3b]

I do not remember it being hard to install the one in my TR3B, but that was many years ago. I saw on another list that they are very low pressure and can be damaged if it is not handled carefully. Warn the shop before they start working on it.

 

[Brosky]

Hey Kevin, easy on the weather digs! It's going up to 36 here tomorrow, ya know!

 

[Harry_Ward]

I just flushed mine out with a garden hose. Gets pretty hot. Enough to where I have to lower the rheostat. Took it out in 24 degree weather a couple weeks ago right before the snow and was very warm. Make sure the heater control valve and thermostat are working properly. I assume it has arrived?

 

[PeterK]

Isn't there also a bolt that goes through the firewall and is held by a nut just above the battery? It also holds a clamp for the brake line that goes across the top of the firewall.

Going from memory here; could very well be wrong!

Good memory. It is the center stud on the bracket that holds the heater up. Hard to get the nut on without a second set of hands or very long arms.

 

[mrv8q]

Hey, Paul, I hate to tell you, but it was at least 80º here; a fantastic turnout at our breakfast club. Most of the guys went to an Automotive Museum afterwards, me, I just drove the one Triumph in my garage that'll start! Wow, what a glorious day! Rain due Monday... I put some miles on for you!

 

[Brosky]

Grrrrrrrrr..............

Rain due Monday here as well....with more #$@* snow and ice.

 

[kodanja]

Grrrrrrrrr..............

Rain due Monday here as well....with more #$@* snow and ice.

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