[Healeys] Radiator cap thermostat combinations

[Mark Donaldson]

John,

In the thread following your question, nobody appears to have
mentioned that the later BJ7s and all of the BJ8s ran a 10 lb
long-neck radiator cap.  All of the others up to that time ran a
long-neck 7 lb cap.

Some years back a friend had major overheating problems in a BJ8.  I
checked the cap and discovered a short-reach 7 lb cap had been fitted.
I replaced it with the correct one and the problem was immediately
solved.

I am surprised that even today many owners do not seem to be aware of
this change-over, or that there are short-neck and long-neck pressure
caps.

Mark
Auckland, NZ



-----Original Message-----
From: john spaur [mailto:jmsdarch at sbcglobal.net] 
Sent: Tuesday, 5 February 2013 11:21 a.m.
To: healeys at autox.team.net
Subject: [Healeys] Radiator cap thermostat combinations

I was checking the archives and read a few emails concerning 7 pound 
caps versus 10 pound caps. The conclusions seemed to be:

7# cap - to stop overflow fill up and let the radiator find it's own 
water level (or use an overflow container)
10# cap - may not overflow but, according to Moss it cannot be used 
with an original style thermostat with sleeve and bellows.

I am not yet too concerned about overheating because I have a newly 
rebuilt four row radiator with the original top and bottom and I have 
not yet driven the car let alone driven it on a hot northern 
California summer day.

Concerning the thermostat, I am wondering if there are significant 
advantages to using an original style sleeved type with bellows? If 
so what are the advantages?

Thank you,
John Spaur
San Jose, CA
'62 BT7