Chrysler 360 pics attached, plugs to remove to pick up hot water heater

[CaptainMark]

Attached are two pics. each shows a 3/8 socket plug.

1 is on the intake manifold top just to the right of the fresh water discharge hose to the fresh water manifolds (1")and the heat exchanger (1 1/2") , I presume on the pressure side of the water pump. (two senders are already installed in 2 other ports,also visible).

the 2nd pic shows a plug on the water pump, I presume on the low side, as evidenced by the return hoses from the manifold nearby to right.

This appear to me in my ignorance to be the best option. The only alterative would be tee cut into the common discharge hose to the manifolds...that seems ok. but I would not want to unbalance that return setup cutting into one of the single manifold return hoses at the yoke on the pump. They are equal length, and flow balanced.

The only other return option I see would be a reducing tee in the main pump suction.(yuk)

I intend to install isolation valves at the motor. a 3/8 to 1/2" or 3/4" hose should flow enough at even a 1 psi difference to heat 6 gal in 30 min. flowing about .8 gpm through heater coil. I do know enough to close the valves to maximize motor cooling and not overheat the water.

I have this basic setup on a mercruiser boat but am unfamiliar with these Chrysler 360's. Its a new dive boat for me, just purchased.

As a diver in New England, I am very fond of my hot water, and the boat lacks a genset.

Thanks in Advance

Capt Mark

 

[kimcrwbr1]

The most common is the port on the intake is pos pressure and there should be a port on the circ pump. Just heat the tank to engine temp and put a mixer valve on domestic hot out of the tank to temper the water.

 

[CaptainMark]

So the plugged ports seen in the photos do make sense? Intake and water pump......

 

[RicardoMarine]

Mark, may I assume that your engine fitted with a heat exchanger using Ethylene Glycol as the coolant?
If so, then what you have is a Closed Cooling system. (fresh water cooling is a misnomer)

With most any Marine Engine (be it an open or closed cooling system) the engine's circulating pump charges the cylinder block with coolant.
The thermostat holds back coolant on as as required basis.
The Water Heater or Cabin Heater coolant supply will always be taken from up-stream of the thermostat, typically from a port within the intake manifold that is prior to the thermostat location.
This area is under mild positive pressure.

The return will always be to the circulating pump's suction side, or occasionally to a fitting that is installed within the large return hose.
This area is under mild negative pressure.



The mild positive pressure (created by thermostat holding coolant back), and the negative pressure (created by the suction side of the circ pump), creates a balance. The balance is what allows the system to function correctly.

So, whether GM, Ford or Chrysler, they all function in a similar fashion.



This is a mock-up of the GM SBC ..... it will be very similar to the Chrysler engine.
Don't be concerned that the exhaust system is not being shown.

 

[bondo]

I do know enough to close the valves to maximize motor cooling and not overheat the water.

Ayuh,.... This is false,.... If it were true, you've have to turn the heater off in yer car,... 'n the water heater takes heat Outa the coolant,....

I'd move the temp switch from the left in the 1st picture, 'n move it to the right of the t-stat, so you can use the port it's in now for the water heater feed, 'n return the water heater's return into the water pump,.....
Hook it up, 'n go boatin',.... the domestic hot water should be good, 'n hot when ya want it,....

 

[RicardoMarine]

.......................

I do know enough to close the valves to maximize motor cooling and not overheat the water.

This is false,.... If it were true, you've have to turn the heater off in yer car,... 'n the water heater takes heat Outa the coolant,....
I agree with Bill. Plumb your coolant supply/return as I described, and you won't have any trouble.
The tempered coolant that supplies the WH or CH will not diminish the system's ability to control proper engine operating temperatures.
Been there/done that many times, and I can tell you first hand that it works.

I'd move the temp switch from the left in the 1st picture, 'n move it to the right of the t-stat, so you can use the port it's in now for the water heater feed,
Yes! This port is "up-stream" from the thermostat...... just where it needs to be for a Water Heater and/or Cabin Heater coolant supply!

'n return the water heater's return into the engine circulating pump,.....
Yep!

Hook it up, 'n go boatin',.... the domestic hot water should be good, 'n hot when ya want it,....


I have a 12 gallon water heater on board. The coolant for this is supplied via my Port engine.
Typically we will have nice hot water in about 45 minutes run-time.
The Pot Engine temperature remains steady.
Likewise with my Stbd engine of which supplies the Cabin Heater.

.