[Tigers] Coolant queston

[Joe Brown]

I've got the regular pressure cap on the original expansion tank and my
understanding was that it would open up if the coolant was boiling over and
the excess coolant would then flow into the catch can.  And then as the
coolant cooled down it would be sucked back into the expansion tank.  Do I
need some other kind of radiator cap?

Thanks,
Joe

On Tue, Sep 8, 2026 at 5:50 PM Gary Winblad <winbladgary at gmail.com> wrote:

> Joe,
> Hopefully you also added the double seal cap?  You need that to make it a
> recovery system, not just a catch can
> With recovery, the overflow is pulled back in during cool down.  That is
> what makes the radiator always full to the top,
> for a few more tubes of cooling.
> Gary Winblad
>
>
> On Tue, Sep 8, 2026 at 3:21 PM Joe Brown <jbbrown1980 at gmail.com> wrote:
>
>> Hey,
>> I added an overflow tank several years ago and I went with one I found on
>> Amazon.  It's called an 800ml aluminum expansion tank from BDFHYK and it's
>> around $25.
>> [image: image.png]
>>
>> I wasn't using the remote oil filter, so I mounted this tank in the
>> filter bracket.  This tank is slimmer than an oil  filter so I had to
>> fabricate a new clamp to secure it.  Here is a photo.
>> [image: PXL_20260908_220938306.jpg]
>>
>>
>> Have Fun,
>> Joe Brown
>>
>>
>> On Tue, Sep 8, 2026 at 4:51 PM Mark L via Tigers <tigers at autox.team.net>
>> wrote:
>>
>>> So, the plastic kit you mentioned will stand up to the heat of the
>>> engine compartment okay?
>>>
>>> In a message dated 9/8/2026 5:18:10 PM Eastern Daylight Time,
>>> winbladgary at gmail.com writes:
>>>
>>>
>>> Mark,
>>> IT is worth adding.  Cost and trouble are minimal. You can buy a kit at
>>> the auto parts store (plastic tank, dual seal cap, tygon hose) for cheap.
>>> Hard to say exactly how much cooling capacity it really adds..  it DOES
>>> keep the radiator full to the top, the extra quart doesn't matter.
>>> I put the tank in the wheel well behind the headlight, out of sight, out
>>> of the way.
>>> A very important reason to add is that it stops the leak of antifreeze,
>>> which is toxic to small animals.  When we were in Big Sky for SUNI, we
>>> stopped
>>> into a small museum.  I will never forget the huge stuffed Condor on
>>> display.  The placard said he died from driniking anitfreeze from an
>>> overheated car... so sad, he was beautiful rare bird.  Please install
>>> the system..
>>> Gary Winblad
>>>
>>> On Tue, Sep 8, 2026 at 7:56 AM Mark L via Tigers <tigers at autox.team.net>
>>> wrote:
>>>
>>> I know some have added an overflow to the expansion tank. This seemingly
>>> allow the expansion tank to be filled to the top rather than only 1/2
>>> full.  Is the addition of an overflow worth installing?  It appears this
>>> would add an additional  1 quart to the system.   How much difference would
>>> this make on cooling?
>>> Thanks,
>>>  Mark L
>>> _______________________________________________
>>>
>>> tigers at autox.team.net
>>>
>>> Donate: http://www.team.net/donate.html
>>> Archive: http://www.team.net/pipermail/tigers
>>> http://autox.team.net/archive
>>>
>>> Unsubscribe:
>>> http://autox.team.net/mailman/options/tigers/winbladgary@gmail.com
>>>
>>>
>>> _______________________________________________
>>>
>>> tigers at autox.team.net
>>>
>>> Donate: http://www.team.net/donate.html
>>> Archive: http://www.team.net/pipermail/tigers
>>> http://autox.team.net/archive
>>>
>>> Unsubscribe:
>>> http://autox.team.net/mailman/options/tigers/jbbrown1980@gmail.com
>>>
>>>
>>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/tigers/attachments/20260908/dc41158e/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 358095 bytes
Desc: not available
URL: <http://autox.team.net/pipermail/tigers/attachments/20260908/dc41158e/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: PXL_20260908_220938306.jpg
Type: image/jpeg
Size: 2513397 bytes
Desc: not available
URL: <http://autox.team.net/pipermail/tigers/attachments/20260908/dc41158e/attachment-0001.jpg>