Heater Control Valve


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New Heater Control Valve

I'm on my second heater control valve in the past 11 years but I'm doing way better then some people who have experienced multiple valve failures. The failure point, or so I'm told, is the diaphragm which can suddenly tear causing the coolant to leak out. When this happened to me, I was able to make it home by running the heater valve wide open effectively by-passing the tear. But the thing about the valve that drove me nuts was the fact that it almost took two hands to open and close the darn thing. It's just a terrible design and there had to be something better out there. I did a post to the Triumph Mail List as well as the 6-Pack Forum and in a day or so I had the response I was hoping for. Robert Jones, a certifiable TR6 nut, from California had hunted down a replacement valve many years ago and sold them at local car shows. Robert is a 73 year retiree who has been collecting TR6's and TR6 parts for over 30 years........but that's a whole other story. Once he told me that Herman van Der Akker, of Toyota 5 speed conversion fame, had this valve in all of his Triumphs I was sold. I paid Robert his $40 plus shipping and the valve was on its way east via Fed Ex. Shortly after shipping it, Robert emailed me to say that he found the part is now selling for $30 so he sent me a $10 refund!! Not too many guys would do that or this...........he told me the part number, where to order it and said to share the info with other enthusiasts. Now that's a real nice guy. So here you go........

BTW......these used to be very easy to find at about $25-$30 but now it takes a bit more searching.

NOTE: Check out Autozone.com for Everco/Heater Control Valve Part# 74648 which is the same at the one below. The August 2012 price was $22.99.

I grabbed this info off the web so that people would have a part number and some car references to use in sourcing one.
And here's the cars and trucks that use this part.

What struck me as funny is that this part is from cars that are actually much older then my TR6. But it's an almost perfect fit and works way better........so very smooth to open and close.

An arrow for the water flow impaired!
On & Off markings make it easy to set up
In the Off position up against the stop bump. The On position also hits the stop.

It's a little different look then the old one but I have no problem with that. If nothing else, people will ask about and probably end up installing one in their car too.

Off with the old!
Side by Side - notice a potential problem??

As soon as I put them side by side I knew I had a little problem. The old valve's hose barb was 1/2" while the new one is 5/8". I have lots of hose barbs left over from my TBI conversion so I figured I'd just grab a 1/2" barb and a 5/8" barb and connect them with a coupler. Then a short length of 5/8" heater hose and all would be well. My only concern was the introduction of two more hose clamps and two more potential leak points. (NOTE: See two pictures at the end of this section as I had to go with barbs after installing new hoses) And then I got an email from Robert saying to "grease up the heater barb and just rotate and force the hose on. So I removed the heater hose from the firewall, smeared some copper anti-seize on the heater barb and heated up the hose end with my heat gun..........and it slide right on with just a little force.

There's no cable lock on this valve so just make a loop at the end of the wire. Which is
easier said then done! Make sure you do your measuring with the valve in the closed
position. The one thing I wish I had done was to pull the inner cable out and then
cleaned and lubed it. I think it will just slide out at the knob end.
FYI..... this wire is miserably stiff to work with!

Everything hooked up and in the closed position

From this side view you can see that I put a small washer over the top of the cable and
then "locked" it in place with a short length of rubber hose.

Another view showing the washer and the hose covering. The wire is so stiff that once
the outer housing is clamped in place, the wire can't jump off the post anyway so the
washer, hose piece & cap are purely cosmetic.

It's about 5 years later and I installed all new hoses in my car and there was no way I could persuade that 1/2" hose over the 5/8" fitting!

So I went the route I initially considered and got two correctly sized barbs and a conector to tie them together. Now the hoses are the correct size for the barbed fitting.

And that's all there is to it. The dash control knob works very easily now and it's infinitely adjustable if you remove the little ball from the knob interior. Robert told me that there's a little ball bearing in the knob that engages the indents that are in the knob shaft. If you remove the ball bearing, it works even more easily and can be opened or closed to any position.

As usual, the first start up after doing any work on the car is always a thrill, not knowing if everything will work as advertised. And this was no exception........as the engine warmed up I got puffs of white smoke from some Teflon thread compound that got on the manifold along with a little anti-seize and some coolant. BUT......no leaks from the valve or the hoses and a quick top down test drive on a 40 degree night confirmed that the heater works just fine!

As my 7 year old grand daughter would say "easy peasy lemon squeezy"