Fine adjustments, forsooth. The main problem with the valve is not flow, but
the fact that the silly knob/cable arrangement is incapable of managing the
full range of valve adjustment from open to closed. Depending on how one
adjusts the cable, you have available either the range from fully closed to
3/4 open, or the range from 1/4 open to fully open. In a moderate climate,
readjusting the cable twice a year may be all that is necessary, everything
else being equal.
Glen, if you are getting nothing out of your heater, it's not the design of
the valve at fault. Assuming the valve itself isn't plugged (this is fairly
common), the heater core is not clogged, and the water passages in general
are in good shape, even 3/4 flow is sufficient to heat the footwells to
unbearable temperatures, with the engine at normal operating temperature (by
this I mean 180-190).
I always suspect the most common problem is running a 165 degree thermostat
-- by the time the water has circulated through the uninsulated hose, its
effect on the cold ambient air from the cowl vent is less than spectacular.
Of course, in truly cold circumstances (not encountered here in coastal
California), the engine will never reach even 165. An oil cooler cover or a
partial radiator cover may be necessary.
on 10/27/03 12:55 PM, Glenn Schnittke at schnittke@mindspring.com wrote:
> Paul,
>
> Thanks. You made my day. Fine adjustments. I like that. Even after the
> valve mod, the heater on my '67 redcar is dismal at best and the thought of
> a fine adjustment between zero and zero got me.
>
> Glenn
> _________________________________
> Glenn Schnittke
> VP - Tennsessee Spokes Sports Car Club
> schnittke@mindspring.com
> '67 B (my daily driver)
> '71 XJ6 Series I (Jeanette's daily driver)
> dead '69 B
> -------------------------------------------------------------------
--
Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the primer red one with chrome wires
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