Cockpit heating

Has anyone disconnected the water lines that serve the cockpit heating system? After changing the heating control valve I still have heat pouring into the cabin and with another summer in Cyprus starting I really want a solution that works. Looking at the diagrams the heating system looks to be served by an separate inlet / outlet lines that spur off the cooling system. Has anyone managed to isolate the heater matrix successfully - preferably as a temporary measure - and if so where in the system did you do this? It looks like a simpler job to do this from the cooling lines rather than opening up the dashboard to get directly to the heater matrix.

Thanks everyone

Nick

The control valve when closed should prevent hot water from circulating in the heater matrix loop.
Have you tried adjusting the cable from the rotating control to the valve?
Try disconnecting the cable from the valve and closing the valve fully by hand. Often the cable isn't adjusted correctly allowing the valve to remain open even when you think it's closed.
The cable can be adjusted at the valve end to ensure full closure by moving the position of the outer sheath at the securing clip.

Note. The clip has a habit of shooting off and disappearing when released. So be prepared!

See this how to. https://www.the-t-bar.com/forum/22-cjj-s-guides/90602-how-to-adjust-the-heater-control-cable

Thanks David,

I have fiddled with that cable several times, even pressing the plastic slider plate fully across to closed before re-securing the cable. I'll have another crack at it but with this being the 2nd valve I have had in place and still not stopping heat coming through it's getting annoying. I notice that even when I did manage to get the valve fully closed the side covers in the central tunnel get very hot - uncomfortable on a bare leg, hence the thinking about physical disconnection to prevent heat transmitting through the static coolant in those 2 pipes.

Kind regards

Nick

My transmission tunnel gets jolly hot, nay, too hot, especially on long runs in mid summer.

I have considered fitting a valve in the engine bay that I can close to prevent any heat transfer into the hoses.

I have also considered altering the layout so that the supply and return come off the main hoses near the front. I assume that the O/E set up is to allow warm water to flow to the heater matrix as soon as the car starts to warm up to aid clearing the screen. This is less essential in my F as I have a heated screen and heated seats.

Hi Nick,
if you have a copy of Roger Parkers excellent MGF and TF Restoration Manual -on page 123 it shows that late TF's had a problem with poor heating which was caused by a missing restrictor in the engine bay cooling pipe junctions. It may then be possible( if your car has normal Northern European heating requirements) to remove the restrictor tube and cause poor heating performance .Once the engine cover is removed it is easy to see this short coolant section and feel it to see if the restrictor is fitted inside the tube.

Mike

Just throwing this out there as a possible cheap fix. As I understand it the problem is the metal pipes in the centre tunnel radiating heat, so why not try insulating these pipes with domestic water pipe foam insulation?

Thanks Mike,

I will get hold of a copy of the restoration guide and see what I can find.

Kind regards

Nick

Hi David,

Metal pipes - never crossed my mind there would be metal pipes inside the car. That I will take a look at. Thanks for the heads up, might be the best solution.

Kind regards

Nick