Electrolysis, I think, David. The corrosion that occurs between iron and aluminum parts from ion exchange.

I haven't seen much of the V-6 blocks, myself. Heck, you can't see much at all on a 3.5 DOHC, and I haven't torn into one...yet.

John B.

[color:"blue"] Question:
With the valve covers off (waiting for the second VC gasket)should I re-torque the head bolts? [/color]


Cleaned up water pipe valley (could use a little paint but not necessary)


Passenger side water pump mating surface (needs light sanding)


Driver side water pump mating surface(needs light sanding)
Seems a little pitted towards the bottom right.




There is definitely a slippery slope involved in working on this truck...
"...now that the valve covers, dizzy, a/c components, etc. are out of the way, I have easy access to install the genII brake booster..."
"...and now that the rad, fan, alternator, p/s and water pump are out of the way, I have easy access to getting the genII UCA's installed...wait, since I need to lift the front end to get the UCS's swapped in, maybe a body lift would make sense..." <img src="/forums/images/graemlins/zombie.gif" alt="" /> <img src="/forums/images/graemlins/zombie.gif" alt="" /> <img src="/forums/images/graemlins/zombie.gif" alt="" /> I could be here for a while.

If the head gaskets aren't leaking, I'd leave them alone. Attempting a retorque on an aged engine might result in false torque readings and start leaks.

After you clean up the water pump flange area of the block, hold the pump against the block (without the gasket) to see if it sits flat against the block.... or if it rocks. If it doesn't sit flat, check to see if there are any high spots on the block - if so, try to get it flat before you final install the pump. If you find a twist between the pump flanges, that might be ok because the bolts will pull it flat.

Frank

Thanks Frank.
The waterpump sits reasonably flat against the block.
There is a very minute top/bottom wobble that disappears when I hold the waterpump tightly against the block, so I think the bolts will pull it tight.

There doesn't seem to be any head gasket leaks so I'll take your advice and leave the HG bolts, and well enough, alone.

UPDATE:
...since I have easy access to the UCA's, power steering gear and M/C and brake booster, I decided to start tackling their replacement with the genII parts I have been wanting/needing to replace them with.
Already have the genII brakes/rotors up front...

genII components:


old leaky m/c and booster:


new booster(doesn't have threads for the check valve but it screws in pretty snugly, hope it's not an issue):


got both UCA's off without having to lift the body, which is good, just have to get the new ones in.
old one attached:


removed:


still need to remove this leaky original and customize genII gear mounting hole to fit:


Once I get the power steering gear off, I'm going to de-grease everything visible and paint it up with a product I used on the rear of the frame called Chassis Saver which has held up very well since the genII rear end swap.

Dave