[DeTomaso] Bleeding the cooling system

[MikeLDrew at aol.com]

In a message dated 4/1/13 13 29 21, will.kooiman at gmail.com writes:


> 
> Also remember, I drove my car as a daily driver, so it went through
> constant heat cycles.  Each cycle would expand into the expansion tank,
> and later suck pure water into the engine - no air.
> 

>>>Which shows the CRITICAL importance of not only a good radiator cap, but 
also the RIGHT radiator cap.   If you have an old, or ill-fitting cap, when 
the coolant expands it will expand into the overflow, but as it cools and 
contracts, the system will suck air past the cap instead of sucking fluid 
from the overflow (which is a more difficult job).   So you are constantly 
introducing air into the system.

Vendors used to recommend a new radiator cap every year or two.   I think 
that's rather excessive.   What is more important is the RIGHT radiator cap.  
 The design of US versus Euro radiator necks is quite different, and a 
standard cap for a US car won't seal properly on a stock Euro tank.   If you 
have a stock tank, you can have a radiator shop braze on a US neck and then use 
a US cap.   Or, you can just buy the proper, Euro-style cap (as used on a 
70s Alfa Romeo).   If you use an aftermarket stainless steel tank, then you 
need to use a US cap.

The surface of the neck needs to be uniform as well.   I've seen stock 
tanks where the top of the neck is rough and pitted, and wouldn't seal properly. 
  You can perhaps salvage such a top with judicious filing, but if it was 
mine, I would just bite the bullet and get a blingy new tank....

Mike