V8-250 Saloon - Heater Box Rod

[classiclife]

Hello,

Having recently refitted the: Screen / Car and Hot / Cold sliders affixed to the radio console, I am trying to figure out what the thin metal rod connected to the heater valve and air box actually does. Currently I cannot understand its purpose when you have a cable operating Hot & Cold and the other cable dealing with the direction; I would have thought the 2x requirements are fully catered for !!

What I do know is that with the rod fitted, it is not possible for the heater valve to be fully open in the Hot position whereas positioning the valve to cold is not an issue as that is the start position for fixing the wire cable in situ; in essence the rod is preventing the full unrestricted movement of the heater valve.

I am tempted to remove the metal rod to gain full swing of the heater valve from hot to cold and vice-versa.

Have attached a couple of photos and grateful if someone can give an explanation re the above plus if the metal rod is of any benefit.

Thank you in advance.

Regards.

Richard.

[KV8]

Hi
Strange I do not have this rod but have a spring in exactly the same location. I cannot see that it serves any purpose whatsoever ?
H

[classiclife]

Hello H,

Thank you for your reply, it is helpful and much appreciated.

With regard to your spring, I wonder if a PO used that instead of the rod - it would certainly make coupling the ends easier. Additionally and I presume having the spring in situ allows the heater valve to travel its full length from cold-hot-cold without issue due to the elasticity ??

What I find very baffling, is that with the rod fitted it actually prevents (as mentioned) the heater valve from being positioned to fully hot. The WSM certainly makes no mention of the rod, but there is no doubt it should be there as per the attached WSM photo.

My only thought is could that linkage on the heater box have been used in some way on the Jaguar Mk2, which had heating pipes to the rear of the car and as such directed airflow to those pipes ?? Perhaps reference to a Mk2 WSM may shed some light on that theory.

At the moment, who can say !!

However, I can the see the rod being ditched pretty soon and may take on the idea of the spring.

Regards.

Richard.

[Alpine Daimler]

Evening all,

I thought that rather flimsy rod operates the Hot/cold position internal flap as super thoroughly described here :http://valvechatter.us/?p=4681

When heater slider control is selected to "Cold" the incoming air is not passed over (or through) the heating element/heater radiator but by means of this internal flap operated by said thin rod is bypassed, or am I having a senior moment? it has been a rather long day over here!

Regards
Rob c.

[Alpine Daimler]

Evening all,

I thought that rather flimsy rod operates the Hot/cold position internal flap as super thoroughly described here :http://valvechatter.us/?p=4681

When heater slider control is selected to "Cold" the incoming air is not passed over (or through) the heating element/heater radiator but by means of this internal flap operated by said thin rod is bypassed, or am I having a senior moment? it has been a rather long day over here!

Regards
Rob c.

....In the murky depths of my pre overhaul heating system it can just about be seen here where it attaches to the internal flap operating crank located outside the then thoroughly grim and flithy heater box......it all looks a lot better these days, was one of those b****r of a job jobs mind you.

[KV8]

It has often been said that as one gets older your long term memory gets longer but your short term memory gets shorter unless stimulated. So some re-invigorated recollections!

Some 5 years ago I removed the entire heating unit to replace the radiator which was blocked. Somewhere I now remember that advice on here or elsewhere was to glue this internal flap shut as its connection (now disconnected) complicated the action of the heater valve. Cold air still circulated via the radiator when heat in off and one also had recourse to the vent. Whatever the PO (in New Zealand) had done this anyway.
Why the spring which I probably diligently re-installed i have no idea!

H

[classiclife]

Thank you Rob and H.

Interesting set of notes on the "valve chatter".

The telling photo is the one I have attached:

The pivot link circled administers the amount the main flap is opened or closed when the Screen / Car slide control is used - think we can agree on that.

However the pivot arm which has the ? next to it, is the one that the rod operates or in H's situation by a spring. The question is: what does that pivot actually operate - I presume an internal flap and if so what is that doing and is that the flap that requires to be kept shut as has been alluded to ??

If that is the case, then it seems to me that the rod can be dispensed with as it has zero use.

Many thanks.

Richard.