Hi Mark,

That's interesting. Did you end up replacing that defective cap with the
same style (with the pressure relief lever), or did you replace it with
something else? If something else, do you happen to know what replacement
caps fit that tank?

John

On Tue, Mar 28, 2023 at 11:29 AM Mark McCulley <mark@markmcculley.com>
wrote:

> In an effort to make my van's coolant system more robust I got one of the
> GW aluminum expansion tanks about a year ago. Shortly thereafter I replaced
> most of the hoses and the radiator. My coolant system was anything but
> robust at this point, I had several leaks. After working on this for many
> hours I discovered that the pressure cap that came on the new expansion
> tank was defective, it didn't release pressure as it was supposed to and my
> system was over-pressurized. It was a frustrating experience, just want to
> relate this and recommend that pressure caps be tested whenever they are
> replaced and when there are issues around coolant leaks. Some parts stores
> like Autozone loan out pressure testers for free that will test the cap as
> well as pressurize the system to check for leaks.
>
> -Mark
> '87 syncro Westy