Mark,
Two of my hoses failed w/in 6 months of each other at about 65,000
miles/7yrs.old.
I replaced all of them.  After that.  They had definitely broken down from
their new as delivered state.

  I've had two pressurized coolant tanks fail, one at about 85,000 miles in my
old '87 and the second one at 59,000miles in my '91.

 I suspect that the failure was caused by over agressive tightening by
mechanics when I had my coolant changed and the systems flushed, done every
two years and just prior to the failures.

Go easy one the caps and tanks.

Jim Woods
Jackson, WY

'91 Westy Syncro