At that point i would have to take it to a shop. The boat sits so high on the trailer that pulling the motor in the garage with a picker just wouldn't work, and I cant (wont) do it in the driveway.
That blows.
Here is what I came up with.
I am working with a phone here with the app so I may be going back in later and editing this.
Water routing.
From the jet pump water port, go directly to a Gate valve. I use a 3/4" Red And White, but brand is not really important but it should be 3/4". I do know that the port from the pump is much smaller. That is ok.
From the gate valve to an open tee, one leg going to each water pump hole in the front of the block.
Out of the thermostat cover (no stat) twice one to each header cooling manifold.
Out of the intake manifold a third time to another gate valve, but this time use a 1/2" from that valve to the dump line. The outlet of the dump fitting (the orifice of the fitting itself) should be about 5/16" max.
Done.
Setting it up.
Start the engine in the water with the pump gate valve mostly open and the outlet valve 100% closed. After a couple of minutes at idle start to close the pump valve until the engine warns up to a very consistent 150°F. Use your hand or an infra red thermometer on the exhaust pipe after the header and try to get the pipe to about 190° F using the outlet valve, own will make the headers warmer, closed cooler and so on.
You may have to dick around with them a little to get then to balance out.
The idle should be about 1,100 or so. Being as we do not know the cam grind. Once you know and/or change the cam we can revisit this.
Take it for a short spin at around 3500 rpm, the temperature should drop, I would expect to about 130 or so. Hit the headers again to see what the temperatures are (obviously be super careful) they should still be in the 200°F range.
It might be necessary to reduce the water flow to the hoses going to each header with a washer to get the engine temp up a bit. Use 316 stainless washers and go with a hole 1/4" you can put the washers right at the hose connection at each water manifold.
Run the set up again.
Once set, this thing will be pretty fool proof. The are no moving parts. That said. Tie wrap the valve handles once you have things working.
The surface temperature of the headers should be around 180°F with a 150°F engine water temp.
There are a couple of other ways I came up with to do this, but this one is the simplest to adjust.
Keep in the back of your mind that with jetting or altitude changes, the exhaust temps will rise and fall. Just keep an eye on it.
Let me know on that cam.
Also too. If you put milkshake oil in a turkey fryer set to about 275°F you can get every drop of water out of it... Making it reusable. Just be sure to change out the filter.
That is a white water guys secret, so don't tell anybody. ..
GT
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