In article
.com>,
" > wrote:

> 4.2 V6 - 160,000 miles. It has been losing water for a while and I
> finally found what I think it is - it appears that water is leaking
> from between intake manifold and block at left front of engine (behind
> alternator, of course). There is no water in oil. Is it safe to keep
> driving it or can the water get into the motor?

Stop driving it, get it fixed ASAP. If it's leaking externally,
odds are that it's also leaking internally. Nothing destroys
bearings like engine coolant!

>Is this a normal thing
> that goes wrong -

I wouldn't call it "normal." It is however a common failure on
mid to late 90s GM V engines.

> what causes it and how do I fix it?

The cause is due to a poor gasket design.
The fix is to replace the gaskets.
Fel-Pro has a problem solver gasket that so far looks superior to
the OEM style available from either GM or Victor.

> I guess the
> manifold gasket has gone bad which means I have to remove the intake
> and replace the gasket?

Correct.
The whole lower manifold can be removed/replaced without removing
the upper (plastic) plenum. Bleed the fuel pressure off but when
you disconnect the fuel lines from the fuel rail, cap the fuel
rail to keep as much fuel in the rail as possible, there is a
history of injector failure post manifold repair due to allowing
the fuel injectors to go dry, keep them wet with fuel if possible.
Use "The Right Stuff" from Permatex for the end (front and rear)
gaskets.