Had water temp buzzer sound with no high temp on the gauge. checked with laser thermo and verified port side higher. swapped temp switch position with temp sender and verified again an gauge. Pressure checked block/heads to 30 psi, no leakdown. Filled and sealed block, heads and removed belt from water pump, fired it up looking for increase in static water pressure due to suspected leaking head gasket. No pressure increase noted. My thinking here was that the leaking head gasket was heating the water on the port side and increasing the pressure on that side causing the majority of the water to flow to the stbd side where there was less pressure. I figured the increased flow to that side was cooling the head too much thus the condensation. My findings did not support my theory. Now I need input.

Vortec small block and or blocked riser - water dump flow that side ?

Looks like you have a better variety of boats than i do ! Want to buy a spare Tahiti , real cheap ?

check for water leaks on the milk shake sides exhaust.sounds like water getting in.

I'm running dry tails dumping overboard, not at the ends of the tail pipes. Lots of flow, 1.25" dump puts out a stream about 2' long at idle. Manifolds have been pressure checked to 40 psi, no leaks. Head temps are 95ish on the milkshake head and 190ish on the hot head. Both heads an the port motor are 125ish. I'm still thinking head gasket even though it didn't reveal itself on the test I devised. Maybe it doesn't leak until sustained high power operation? I can remove the thermostat and loose the high temp warning and the hot head will stay around 135 but the milkshake side is still about 95. Water pressure with stat installed is 5 at idle and less than 25 at WOT. Keep it coming because this has got me scratching my azz.

I'll try to post some pics of my Tahiti. It's a 69 with a L-88 427, (original installed by AeroMarine for Tahiti), Original black gelcoat is still pretty shiny and the original white vinyl interior is almost flawless as is the original carpet. I bought it from the guy who bought it new in 1969 three years ago. It's had 183 hours on it then and the trailer was sporting the original tires. Motor has never been removed. Sal, the guy I got it from took the manifolds off every winter and stored them under his bed. Its a really special piece and I feel fortunate to own it. Only drawback is it's got 12 to 1 comp ratio and require avgas LL100 or race fuel. My buddy Endeavor1 has seen it, maybe he'll chime in. Its a very cool boat. I'm kinda proud of it as you can tell.

x 2.

Maybe even a head bolt or two letting some water seep in. Doesn't take much to whiten the oil.

BTW: On land and on a hose, I usually see the Port side have less water flow and higher exhaust manifold/riser temp. This is with Merc system. The starboard side will flow water out the tailpipe well before the port side when first started. Just my experiences.

I'll check them again. My oil is clear, just have condensation under the valve cover in the one side and on top of that same head. I'll check the head bolts, they were not retorqued after build.

I understand. A few drops of water from a head bolt will just make a little condensation / whitish oil in a small area. Won't turn the oil in the pan white.

In fact, anybody with a Jeep Liberty will attest to the white junk oil collected on bottom of fill cap. And that's with no water coming in. Must be because of being higher than where the PCV does it's venting or just not enough venting...I dunno..

Two more things.

Intake manifolds more common to need retorquing than heads. So make sure to retorque that too.

2nd, many aluminum valve covers have a tendancy to sweat a lot, causing condensation inside the cover. The steel cover's do not. Aluminum just loves to sweat...lol.