Just a few comments:
My BN1 has a 160 degree t-stat and will maintain its temperature at or
a little above that point under any conditions of load or ambient
temperature as long as it is moving. That indicates to me that the
cooling system is in good condition as far as it goes. However, when i
spend any appreciable amount of time idling in traffic or at a few of
the ubiquitous and interminable stop lights that grace our fair city
(I think the mayor's cousin sells the damned things.) the temperature
will rise very quickly. That leads me to suspect that the problem is on
the air side. This makes sense since some of the local operating
conditions are outside of Austin of England's design parameters.
Although Donald spent a lot of time in this country testing and
checking out operating conditions there are a few things he missed.
The cooling system may be great at sea level and under ambient
conditions for blighty, but how do you design for 5000 feet of
altitude, high desert temperatures, unanticipated high average speeds
on crowded, endless interstate highways and stop and go traffic while
at the same time maintaining some bean counter's price goals.
The cast alloy fan is cute, but it is crap for efficiency when you most
need to move air, that is while idling.
The radiator is fine as long as the air is moving, but the envelope
body mitigates against air movement when the car is standing still.
The close engine compartment restricts air flow even more and
concentrates heat from the engine particularly radiant heat from the
exhaust manifold.
The front carburetor's float bowl and jet feed passage is directly
exposed to the radiant heat of the exhaust manifold and, under extreme
conditions, is prone to vapor lock.
These things being said I find that even though the engine temperature
rises under these conditions the engine runs fine up to a point above
212 degrees when the carbs will start to load up (vapor lock). If you
spray down the carbs with a little water it all goes back to normal. I
don't think the engine cares much about the extra BTUs until it gets
well beyond the range of the temperature gauge.
I'm all for modifying what can be changed to make the cars operate
better and last longer, but I think at some point we need step back and
remember that this was the state of the art in Great Britain circa 1953
and the car is never going to be an Acura (and I thank God for that).
Bill Lawrence
Albuquerque, NM
On Jul 7, 2004, at 6:33 PM, John Snyder wrote:
> Well, It is still running hot at idle.
>
> I removed the air baffles which push air to the radiator (BT7 MK2) and
> modified them so that they extended past the sides of the radiator and
> fit
> tight. Also added tabs at their top so that the baffles go all the way
> up to
> the bottom of the radiator top tank.
>
> Took the car for a short drive on local streets. It ran on the
> thermostat
> setting. Came home and let it idle in my shop (hood closed) where the
> temp
> was 70F. It took 3 minutes to go from 165F to 190F. At this point
> I give
> up!! Everything on this car is to spec.
>
> John Snyder
>
> ----- Original Message -----
> From: "M Lempert" <mlempert@bellsouth.net>
> To: "Healey List" <healeys@autox.team.net>
> Sent: Friday, July 02, 2004 6:35 PM
> Subject: Re: Hot Problem
|