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Hi Rick,
yes I meant hoses not pipes.
This is how I interpret the water flow for a closed system. I may be wrong!!!! I am just trying to save $800!!!
In your pic of the thermostat housing which is about the same as mine, the yellow closed water would still go to the circulating pump. (no change)
The T-stat housing image that I posted is designed for use with a raw water cooling system.
It it not designed to work with a closed cooling system.
For a closed cooling system that cools engine only, a single return outlet T-stat housing is what you will need.
Perhaps something like this one, but with an angle that fits your needs.
Note that this is a single outlet T-stat housing... which means that the coolant return port on the H/E must also be a single return.
The RH blue arrow would be cool water from the HE going into the thermostat housing.
There will be no water within the engine side of the H/E.
This will be ethylene glycol only.
The hot water from the engine (red arrow) would still mix with the incoming cool water from the HE
No mixing will occur with a closed cooling system.
The two blue water outputs would now return to the HE instead of going to waste via the exhaust manifolds.
Now I'm a bit cofused.
Are those SS (what appears to be 1 pc) exhaust manifolds similar to what you'll be using?
There obviously has to be a return path for the hot water to the HE so as to be cooled.
No... no hot water returns to the Heat Exchanger...... only heated ethylene glycol returns to the H/E where the seawater will remove the heat from it.
The seawater will remove the heat via the tube bundle.
The seawater will run throught the tube bundle.... and the ethylene glycol runs around the tube bundle.
The flow of water from the engine (red arrow) would be controlled by the thermostat. would it not??
Yes, if you are refering to my image... but please note that this is designed for raw water cooled engine.
There will be NO water in your engine.... only ethylene glycol (with a touch of distilled water for the mixture).
Hi Rick,
I think that you are regarding my use of the term 'cooling water' to be raw water.
Yes, I was!
Where I use the term cooling water I really mean ethylene glycol in your terminology.
I believe that the term is accepted world wide.
In Australia we do not generally have a problem with freezing so ethylene glycol is not often refered to. So I used the term cooling water to mean all the water within the closed circuit of the HE and engine .
In my opinion, a closed cooling system is rather pointless if you do not plan to use Ethylene Glycol. The PH balance of plain water is certainly against us.
The raw water being the water that is pumped through the tubes of the HE and out through the manifolds.
Yes... now we agree!
Does this make my earlier post seem a reasonable way of implementing the plumbing??
As to your question.... nothing on my end changes.
You'll still need the T-stat housing that I've suggested.
I'll ask again... does your kit not include all of the necessary parts?
Thanks Rick for your continuing connection to my problem,
I did ask for advice from "Marine Direct Australia" and their tech advisor (in the US I believe) agreed with me that the MDA91036 was a good choice.
I was informed it was suitable for 'block only' cooling on my 5Lt. V8.
Do you have a GM 5.0L V-8..... or a Ford 5.0L V-8?
I ask because if the company thought that your engine was a Ford 5.0L, they may have suggested a Heat Exchanger with twin coolant inlets due to the Ford style T-stat housing similar to this one.
If GM 5.0L V-8, and for the correct Half System with a single coolant return port, you need this style.
I suppose that you could use one like this if you keep the twin return H/E.
I chose the 41/8" dia. X 21" so as to give me a bit more cooling capabillity at high power.
The 5" dia. HEs which are also available are for FWC according to the data.
I am not understanding that one.
The term FWC for some means Fresh Water Cooling (one of my pet peeves), and is used in a misnomer fashion to describe a Closed Cooling System.
This has been carried over from years ago when Keel Coolers were used.
There's nothing fresh about Ethylene Glycol ..... ya can't drink it, ya can't wash up in it and ya can't cook with it!
Although a great deal of the Marine industry does use the term FWC, technically these are Closed Cooling Systems!
Thank you for going to the trouble of drawing up the coolant and seawater circuits.
Your circuit for 'Half System" is what I will be using. I would think that I would connect up the two coolant return ports with a 'T' piece and connect a single hose to the thermostat housing. The seawater return would be connected via a 'T' piece to the two SS manifolds.
As I suggested and illustrated, this must incorporate a diverter or splitter... otherwise the flow to each manifold may not be equal.
Unequal flow may cause one side to run very hot.
The suppliers have even agreed to fit 1/2" feeder hose connection to the HE for connection of a resevoir bottle so that I can mount the assenbly below the top of the engine and avoid air problems.
You should not have a problem purging air from the system.
The #MDA91036 heat exchanger mounts at the front of the engine elevated above the Circ Pump.
The actual thermostat will have an air bleed hole in the flange.
All I need now is to try and avoid paying out another $800 for a T-stat housing, which is more than 60% of the whole HE assembly!!!!
http://www.ebay.com/sch/i.html?_fro...+housing&_nkw=sbc+thermostat+housing&_sacat=0
Hi Rick,
My Volvo 5Lt V8 uses a chevvy small block.
{I chose the 41/8" dia. X 21" so as to give me a bit more cooling capabillity at high power.
The 5" dia. HEs which are also available are for FWC according to the data.
I am not understanding that one. }
I used the term FWC to mean "Full Water Cooling" (block and manifold) a term which I have seen used on other forums.
I guess the problem is that between the US, Europe and other countries the abreviations differ widely and can certainly cause confusion.
Apparently so. Our communication has been somewhat complicated and difficult.
If GM 5.0L V-8, and for the correct Half System with a single coolant return port, you need this style.
This style of T-stat return port is what I believe I require.
This is NOT a return port!!!!
This is the Thermostat Housing of which directs the coolant FROM the engine TO the heat exchanger after it exits via the Thermostat.
I have sorted the configuration of the closed-circuit-system thermostat which works so as to bipass coolent back to the top of the engine coolent pump via a spring loaded plate on the bottom of the thermostat which then closes at 70deg C.
Who is suggesting that this is necessary on a SBC?
I do have one concern, based on advice from new found friends in the water area I am in, I have decided to fit a RW filter/strainer.
Must this strainer be fully below the level of the raw water intake pipe so as to allow the RW pump to be always primed??
Pictures?