I've got a '97 (212k miles) with a 4.6 that has developed a mysterious water leak.
It's not the heater hoses.
I do not see any evidence of a leak around the passenger side rear like a head gasket leak might look like. It shows up after revving a little dripping off of the bell housing right in the middle of the truck. And it's a pretty good leak.
How likely is it that the o rings on the hard line under the intake manifold might be the problem?
I've looked under the alternator, but I'm not too sure I'm seeing the actual engine block. There might be a valley pan that covers the hose coming out of the water pump. Is that the case?
Is there a definitive way to see the hose connection that I've seen posted on this forum without pulling the intake?
Thanks

 

Check your freeze plugs.

 

I have had a look at the plugs that I could see. As it turns out, two years ago it dumped all the water in the oil through a corroded freeze plug behind the timing chain cover, so I'm pretty sensitive to those.
Any thoughts on the line under the intake?
I can't see the line itself. I think I'll go out there and look at the back side of the alternator now that I've had it running today. It started to overheat on the way home last night (late), I saw water coming out from under the truck. I pulled the right inner fender to get a better look at the situation behind the passenger side of the engine. I've felt all over the heater hoses too.

 

I just went out to the truck and crawled all under it. as it turns out, without the engine running, it still drips. Probably just due to head pressure. A steady drip.
The curious part is that it appears to be coming out of the rubber plug at the bottom of the bell housing. I pulled the plug out and sure enough, I see drips falling off the bottom tooth of the ring gear.
Are there freeze plugs under the bell housing?
It's a 4X4. How much of a job it it to pull the tranny out and replace it if there are plugs in there?
I have had a number of two wheel drive trannys out, all manual. Looks like a really big job. I have an adapter for a transmission to go on my floor jack.
And what benefit would I gain from replacing the tourque converter to eliminate shudder while I'm in there.
This may all be premature at this time.
Thanks

 

At the rear of the manifold is a tube that is pressed to the manifold. The truck I'm working on has blown this tube out, I'll bet you've got a leak there where the tube and the intake fit together.

 

It turned out to indeed be a freeze plug behind the bell housing. Three tiny holes corroded right through. There were two, changed them both. This truck had another one leak two years ago behind the timing chain cover that dumped all the coolant into the oil, making me (and everybody else) believe it to have a blown head gasket or cracked head. Add 15lbs. pressure and you have a pretty good leak. While in there I changed out the torque converter to stop the shudder. Fixed that as well.
Thanks to all that replied.