Indeed.
I saw one subaru conversion that puffed up a New Expansion tank like a
volley ball.
In that particular  case...head gaskets .

On 7/20/2016 2:55 PM, Jim Felder wrote:
> I know there are some crappy tanks out there but if you are blowing them
> that fast it almost has to be combustion gasses.
>
> Jim
>
> On Wed, Jul 20, 2016 at 4:35 PM kenneth wilford (Van-Again) <
> kenwilfy@comcast.net> wrote:
>
>> Have you checked for combustion gasses getting into the coolant?  What
>> brand of tanks are you getting?
>>
>> Ken
>>
>> On Wed, Jul 20, 2016 at 5:27 PM, Stan Shapiro <mail@stanshapiro.com>
>> wrote:
>>
>>> I am on my 4th NEW coolant expansion tank in about a year.  They leak at
>>> the
>>> seam.  Any suggestions for a replacement?    I have seen the metal tanks,
>>> that I am sure are bullet proof, but I do like the ability to check the
>>> coolant level in the expansion tank just by looking through the plastic.
>>>
>>> Suggestions?
>>>
>>>
>>>
>>> stan
>>>
>>
>>
>> --
>> Thanks,
>> Ken Wilford
>> John 3:16
>> www.vanagain.com
>>