OK Folks,

As it seems we are all hot and bothered by this subject I have another
wrinkle.  My 91 with a rebuilt engine has had bouts of popping
hoses/coolant system leaks since about 2 mos and ca. 750 miles since
installing the rebuild.  As I don't have a shop that I trust locally (or
alternately a shop I trust that doesn't work on these vans) I have been
fumbling around trying to solve the problem by curing the symptoms.
Yes, I know this is not the best way to go.  Here are the facts:

The problem:

Leaks at the weakest point so that after several miles the volume in my
pressure tank "drops" about 1-2 inches.  There is coolant in the
overflow, but it never sucks back into the pressure tank.  The system
pressurizes and force coolant out the weakest link ( which keeps moving
as I resolve those).

New Parts:

- coolant hoses in the engine bay
- thermostat and housing
- radiator
- coolant pump (actually that got put on the original engine and I
transferred it within 1,000 miles onto the rebuild - new gaskets of course)
- pressure tank
- three (yes 3) pressure caps

Option 1: methinks the over-pressure could be a problem due to flakey
coolant tank caps, but hey, I got three and even if I swap 'em out I
have the same problem.  Possible I have three bad ones, but not probable

Option 2: The line from the pressure tank to the overlow is blocked.
Negative.  Taking the line off at the pressure tank I can blow through
it an get bubbles in the overflow.

Option 3:  I have lots of point in the system that are leaking before
the valve in the pressure tank cap "lifts".  Again possible but not
probable.

I have tried using a NAPA coolant block detector, but that came back
negative when I did it a few months ago (i.e. no combustion gasses in
the exhaust system).

To the questions:

Has anyone in the list cobbled together a _simple_ coolant system
pressure indicator?

Without knowing if the system over pressures from the get-go or builds
pressure  slowly, anyone want to take a a stab at the solution?  I'd
bite the bullit and would pay to have this thing tested, but I've had
really bad luck at the local dealer and an independant shop and the
respected shop is about 1.5 hours away and charges about $100/hr.

I'm about to drill out the spring in one of my pressure caps and let it
flow to the over flow at atmospheric plus a little pressure.  No, not
really, but this is becoming a rediculous pain in the tuckus.

Thanks in advance,

bem-stem