Re: Help debugging core leak

["Lino M. Valadas" <valadasl@osha.igs.net>]

Hello all

My 86 5kqw has what it looks like a heater core leak.  The smell of
antifreeze when the heater first starts, a little fogging of the windshield
occasionally and the fluid level going down in the overflow container.  The
problem is, this is the second new core that I replace within the last 30
days.

The original core started developing the symptoms described above so I
replaced it with a new third party unit, which is an all copper unit.
Immediately after installation the symptoms were still there, only worse.
Bummer, I got a bad unit, I thought, so out comes the heater core, again,
and replaced it with another new unit from the same supplier.  The problem
is still there.

One small problem with the replacement units is that the tubes going into
and coming out of the heater core are slightly smaller in width than the
original ones.  I've compensated by using two hose clamps on each hose and
everything appears to be dry there when I check.  Besides the pipes are
outside of the heater case and even if it leaked there shouldn't go into the
case right?
Any ideas?  I really don't think I have another bad core and I'm getting
tired of re&re the heater unit.

TIA
Lino
86 5ktqw
83 Ur-Q