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Ecotec Coolant Flow Diagram

wannaeatyourbrains

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Could any of you guys help me with a coolant flow diagram or picture from the manual showing the plumbing, please?

I got a VY with the 3.8 Ecotec. No hoses on it or hoses incorrectly hooked up. Everything is a shambles and I want to put it back to rights.

The two nozzles coming out of the side of the water pump are for the heater hoses, right? The heater has been disconnected, and the hose on one of those pipes went down to a nozzle near the oil filter. Other one is missing.

How come it has that nozzle near the oil filter anyway?

If you could show me the correct coolant flow through the engine and how to restore it to factory, much appreciated.
 

altonarona

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See attached images for factory setup of the hoses
 

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wannaeatyourbrains

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Thanks a lot, mate. Very helpful. But what is the spout coming out of the oil filter housing?

The inlet hose 9D had been rerouted to it because the heater tap was broken. Car was running for ages with it like that.
 
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wannaeatyourbrains

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Right, here is the car.

1647866146646.png


Here are the heater inlet and outlet.

1647866222301.png


Someone tore the wires off the oil switch. Red. Great.

But this one has two spouts next to the oil filter. Is it a water jacket to cool the oil?

1647866316227.png


9D heater inlet was connected to the bottom spout. Can you tell me what is going on with these, please?
 
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Skylarking

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The thing between the oil filter and block looks like an oil to water heat exchanger. Water goes into one pipe and out the other while oil passes through the unit towards the filter and back into the engine. Obviously the oil passages are separated from the water passages else bad things can happen.

Dont know if these are standard on all V6’s or it it’s just for some markets. I had one on a 4 cylinder turbo and it was a PITA as to get the replacement hoses as they were NLA…

PS: there are also similar looking sandwich plates that have a oil thermostat within and can pass filtered oil back to the block or bypass the oil return via a front mounted oil radiator and back to the block… But that’s not what you seen to have judging by yje rust around the pipes and the fact they were connected to coolant hoses… I prefer such oil to air radiators…
 

wannaeatyourbrains

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OK thanks. I wondered which is in, and which is out. And where it would have been connected originally. Maybe there was a different kind of heater tap - different to that manual I was given - with spouts on it that went to these ones. The remnants of the heater tap are still in the engine bay attached to the hoses from the firewall, but it is too busted up to tell.
 

Immortality

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That fitting on the oil housing isn't standard as far as I'm aware.

In or out on the oil housing adaptor doesn't really matter
 

wannaeatyourbrains

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Yeah, thanks. I wonder if there was something in there originally to radiate a bit of heat out of the water? Bit of metal piping, I mean. I cannot find a picture of anything like it, on a Buick or Camaro or anything. Seems odd that it would just circulate hot water straight out of the block to cool anything. I think I will go to the wreckers and check out the ones there.
 

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This is the first one I've ever seen fitted on a Commodore.

A water-oil heat exchanger will help the oil to heat up on a cold start (engine coolant gets up to temp much faster than engine oil), once everything is up to temp, oil tends to be warmer than coolant so the cooling system will help to cool the engine oil a little. How effective is it? I'm not sure. It's common to see things like this though on other makes, my boys Subaru's have them fitted and I think my other boys BMW might have something that does the same thing.
 
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Skylarking

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The water is taken from somewhere within your engine's cooling system, probably the heater outlet at the water pump, and directed to the oil/water cooler inlet. The oil/water cooler outlet is then fed back into the engine cooling system, ideally making its way back to the main radiator without having to go through the engine block. With your oil/water heat exchanger (the correct term for these things) it doesn't really matter which is the water inlet or outlet. In any case its the airflow through the main radiator that will cool the coolant and the cycle to pick up heat from the engine and oil cooler begins again....

It's not a separate system that you sometimes see used to cool the incoming compressed air on a turbo system. These sometimes use their own pumps, piping and remote radiators (all separate from the engine cooling system).

In your case, it just looks like something similar to the following was added:


The one i had in my car was just a spin on oil cooler that takes the place of the oil filter and then the oil filter screws on to the oil cooler. Plumb it into the engines cooling system and bob's your uncle... Also don't remember them being crazy expensive like the above Duratec one ... but guess its inflation ...

There are many liquid to liquid heat exchanger designs. One other type is shown in the video below.

 
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