Radiator stop-leak?

[David Head]

What happens is the water pump bearing seal starts to go - under pressure (hot and
running). The rear cover directs it down the front of the engine - its hot enough
that it vaporizes on the way. As the engine cools after shutdown a slight vacuum
forms as the water contracts - enough to prevent it from leaking. With the cap off,
the weight is enough to cause it to leak (usually). Once they start, it will get
progressively worse over a 3 month/3000 mile period, followed by a catastrophic
failure...

"Doyt W. Echelberger" wrote:

> My mechanic guessed at "water pump"  right away. But he wasn't as helpful
> as you.  Now I know what to do and what to look for.  Hope you are right.
> I'd rather fix a water pump than a head gasket.
>
> Thans.      Doyt
>
>  >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> At 08:12 AM 9/30/2002 -0400, you wrote:
> >Its your water pump. Next time you park it, remove your reservoir cap. Look in
> >the front of the oil pan after several hours.
> >
> >"Doyt W. Echelberger" wrote:
> >
> > > I can't explain where about a pint of coolant goes every week.  No external
> > > drips or puddles or wet spots.  After about 200 miles of driving, I have to
> > > top up the overflow reservoir.
> > >
> > > I know the answer is  "Find the leak and fix it."  But that doesn't seem to
> > > be happening. I've been following the "coolant system gases-saga"  thread,
> > > and I too may have a head gasket leak.  My cabin floor isn't wet.  My next
> > > move is to get my mechanic to run a test on my coolant, for exhaust gases.
> > > If that returns positive, I do a head gasket.  But if that returns
> > > negative, I'll consider some kind of stop-leak. I've heard that car
> > > manufacturers use it routinely in new cars, because they all leak.
> > > (Probably a myth.)
> > >
> > > Anyhow......Did anybody ever try that dry aluminum flake material in a
> > > tube, that claims it will never harm anything in the coolant system?  Every
> > > gas station carries it and it has been around for 50 years.
> > >
> > > I figure the coolant is going somewhere that is hot enough to evaporate it,
> > > and it only leaks out when the engine is running, and it gets blown away in
> > > the stream of air that whips through the engine compartment. Maybe it gets
> > > spread out on the surface of the hot engine, and gets evaporated that way.
> > > And maybe it is getting pulled into a combustion chamber and becomes part
> > > of the exhaust gases.
> > >
> > > Anyhow, maybe some stop-leak will plug up whatever tiny channels are
> > > causing this loss. But I'm not sure what else will get plugged up with this
> > > powdered aluminum stuff. Channels in the heater core?  Opening in the
> > > thermostat? Lines to the turbo?
> > >
> > > Any bad experiences with stop-leak?
> > >
> > > Doyt Echelberger
> > > 87 5ktq at 255k miles, in Ohio   USA