BritishV8 Forum

General Category => Triumph Sports Cars => Topic started by: BlownMGB-V8 on September 15, 2009, 03:34:09 PM

Title: TR7 heater control valve replacement
Post by: BlownMGB-V8 on September 15, 2009, 03:34:09 PM
Apparently the original is no longer available and the only ready replacements are either a manual valve or a valve relocated to the engine compartment. I wanted to open the valve using the existing controls so I used a 4 seasons valve #74000 and made a bracket to locate it in the stock position. I had to relocate and slightly bend the control arm and the valve operated backwards so I had to attach the control rod to the primary rod rather than the secondary bellcrank arm like the original. But as completed it appears to work as you would expect. The #74000 cost about $30.

Jim

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Title: Re: TR7 heater control valve replacement
Post by: dwtr6v8 on September 18, 2009, 11:40:30 PM
Sweet modification Jim

But you would not need a heater if you put a V8 in it.
Title: Re: TR7 heater control valve replacement
Post by: BlownMGB-V8 on September 19, 2009, 12:04:43 PM
Really Don? Well, considering it has the Buick V6 I guess a set of headers is all we'd need to go to the small block Buick V8, 300, 340 or 350. Would that be acceptable?

Now look. This is Edith's car. She doesn't need all that power and the 231 will be just fine. She does need heat. And an auto tranny. So lay off! ;-)

btw, the retail on that #74000 valve is more like $37. If there is any demand I could make up a kit for it but the cost is probably going to be double that. I'm guessing there might not be enough tr7's around to make it worth doing though.

Jim
Title: Re: TR7 heater control valve replacement
Post by: cliff on September 24, 2009, 03:02:04 AM
Jim, Auto Zone has a direct replacement heater control valve from the original mfg. Ready Aire #5864 for about $50.00. Also available for 1970's era Volvos. Get the TR application, its the same valve but way cheaper than the Volvo appplication.
Auto Zone also has the A/C expansion valve available.  Hope this helps.
Clliff
Title: Re: TR7 heater control valve replacement
Post by: BlownMGB-V8 on September 24, 2009, 11:05:28 AM
Interesting. Too bad I didn't know sooner. I'll pass along the info to Woody.
The original valve is a complex item. It is a thermostatically controlled valve which is operated by a capillary tube, the bulb of which is buried somewhere deep within the bowels of the HVAC unit, and as such it is capable of maintaining a relatively constant temperature output, handy for long trips or to just set and forget. This one will no longer function quite that way, as the flow is now controlled manually but this will be acceptable as Edith would not make use of the automatic function in any case. It'll do fine. But it looks like there'll be no demand for this mod.

Jim