MG T-ABC

Is there any way to install a Arnolt Heater in the TC so as not to damage the car so it could be uninstalled if desired at a later date and not have permanent holes etc to fill ?

I don't know about the Arnolt, but I have a K - L aftermarket heater in TC2911 and I have used a couple of the existing oem holes down on the firewall just behind the engine to route these hoses. It may take a bit of moving things around but it can be done. After welding up the holes some previous owner sloppily cut into my firewall there was no way I was going to add my own. Be sure to use grommets.

Holes in the firewall aside, I have a general request on heater installation for a TC. Here in the resources section, technical articles, "TC Heater" (second one down in tech articles) by Art King has likely the best
pics to show a typical heater install. Like other sources it shows the return pretty well, and does show the
general idea of where the supply can come from. Other sources do not show the supply at all, while others argue about where the best place to take the supply from is. Taking it from the back of the head as Art King
did seems to make sense, but curious as to what others think. Also, if someone could post a pic of what their
supply take off looks like, I would find it most helpful. Thank you-

In the days I had a "Bosch" heater installed in my TC- not to heat, but to cool down the engine!) I took the intake from the back, adapted the lid on the back of the head, also with a shut off valve. Worked fine.
Now after restauration not more needed.

Source of coolant for the heater needs to be where the coolant is coming out of the engine. Absolute best place for hottest coolant is in the front off the curved housing right below the thermostat, which requires drilling and tapping for a pipe outlet.
Good place for return is the back of the cylinder head, with a valve in place here.
Many have done source and return off the coolant bypass pipe at the front of the engine, making a diverting pipe. Personally I don't think one gets sufficient hot coolant out of this setup.
Hope this helps. Others likely know more.
Tom wilson

Tom-
Either method you mention (housing below thermostat, or coolant bypass pipe) for supply of hottest coolant, and return to back of head would seem to follow the direction of coolant flow in the XPAG. That is, collecting heat as coolant flows from back to front of the head. See Gene Gillam's article in tech articles. I suppose those with a modern thermostat retrofitted, with bypass severely restricted, might have some problems getting a good supply of hot from the 2nd method.

A couple of shots of the take off and return hoses both running through existing holes in firewall.

Stephan, is it just the picture losing depth of field or is the front hose very close to the manifold.


I always replace long lengths of rubber hose with copper pipe and short joining pieces of hose. I've seen too many split hoses to know that they are a good cause of breakdowns.

Another point (sorry to be picky) but lagging exhaust downpipes is OK for racing engines which get rebuilt each season but the lagging transfers the heat both ways, further down the pipe and back into the engine. The exhaust valves can be overheating on long runs which will lead to premature (or accelerated) wear.

Once again, sorry to be critical, I hope I haven't offended.

Not at all. Yes metal tubing is fine, but the hose is well away from the manifold outside the carb drains, there are many ways and techniques to run it as one prefers, keeping in mind that a TC doe not have a pressurized cooling system. I assume the term "lagging" refers to the fiberglass wrap on the downpipe and again I have dabbled with this stuff over many years on street engines and have had no issues, done and forgotten. The downpipes on my Morgan Plus 8 which really does have a sultry cockpit on warm days also have been wrapped for years and years without issue. I think the amount of heat this stuff really insulates is not that great anyway, probably more marketing hype than anything. I do not wrap headers although the manifold on the TC was ceramic coated, again I think more marketing than anything.