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Triumph TR6 - heater control valve

Where can I get a better quality heater control valve for my 73 TR6? The ones from the normal suppliers only seem to last 2-3 years, then start leaking. I use only distilled water and antifreeze in the system, so I'm not sure why they don't last longer. Thanks

I can't answer the "quality" question about where to get a better valve. Maybe try a 6-7 psi radiator cap instead of a 12-13 psi cap.
Brent B


Who do the parts come from? If its Moss or TRF call them and explain the situation.

There are some supliers with bad to junk products I hear?

My TR is a 72 3rd owner for 19 years and I think my valve is original no leaks so far. Even in Canadian summers the defrost and heat are sometimes used.

Check Brents thoughts? If its not used on a regular basis may cause seal problems?

Let us know may help others make decisions.

Bill Brayford

Since we're on the subject of heater control valves, I was wondering if anyone has the same problem as I do. I have a new valve and the dash control is not able to shut it off completely. That last little bit requires to much effort for the cable to push. No problem turning it back on since the cable is pulling rather then pushing. Seems like an inferior aftermarket part. I end up lifting the hood and doing the rest by hand, not a big deal, after all that's the "British Experience". But if someone has the same problem and perhaps overcome it I'd be interested in knowing.

D.W. Campbell

I think what you see is what you get. I agree with Bill, complain to your supplier. I think they all come from the same place though.
Doug: mine does the same thing. During the hot months the "hand" push closed is where she stays. Spring and fall, when a little foot warmth is needed I just use the knob. I do not see a way of correcting as there is to much flex in the steel braided cable.
Bill: The demister works in a TR...? Ya learn something every day:) When I got my 6 certified I had the heater "bypassed" and was told the car must have a functioning defrost system...I chuckeled to myself, replaced the 2 hoses to the fire wall. He said there is no air coming out of the 2 dash vents... DUH!!! the car is standing still...what do you want for a 30 year old car!! He was almost tempted not to certify it or get a stronger blower motor! Needles to say that is the last time I have been to his shop. ( Oh Ya, he insisted he had to take the car for a test drive...GEEESSS ya do not even need a motor in a car to have it certified!!!).
Rick C
Rick Crawford

D.W. - You need to move the cable sheath forward (towards the lever) some to get it to close. Move it up about 1/4", try it then.
Brent B

Hi Doug
You might find after a bit of use this sorts itself particularly if you follow Brents suggestion, I had this same problem with an MGB which has basically the same crappy valve and thats what happened. also a little oil on the actuating mechanism of the valve doesn't go wrong
R. Algie

Mine is the same way last 1/4" by hand. Brent when you refer to the sheath I assume you mean the hard casing around the cable I will try this and see what happens.
Thanks, Keith

Those who use only original material may not approve but I used a heater valve from a Honda Civic. Bracket needed to be adapted a bit but it works very well. No sticking and binding. I did have to re-locate the cable itself. I took a chunk out of the heater box so the cable has a natural flow to it instead of the factory bind.
Richard Porter

I have same problem, in the summer the heater core
heats up from the side that isn't closed and radiates
heat into the footwell. I fixed that by installing
a half inch brass ballcock gas fitting from Home Depot.
I installed it on the return hose from the heater core,One turn and and all heat stops. Then just turn it
back on in the Fall.
Christopher Trace

This thread was discussed between 26/05/2003 and 29/05/2003

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