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Turbo Coolant Source and Drain Locations

4169 Views 17 Replies 4 Participants Last post by  Jeremy S
Hey guys,
I hope all is well with you guys.
So lately I decided to change turbos on my 1.4L D14 and go for a smaller one for a faster spool.

The smaller ones require a coolant supply and a coolant drain and to be honest I have no idea where to to even get these. Maybe I could T the temp sensor(and that could be feed I guess). The thing is im not really sure what would be the best way to go.
Appreciate any help you can give me.

Im attaching a picture of the coolant system which shows the majority of coolant pipes. Let me know if you need more.

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Ok, so in one of the posts one guy is using the line from the IACV (which originally goes to the water line) as the feed and then from the outlet of the turbo he loops it back to the waterpipe nipple.Did I understand him correctly?
Depends on the size of your tubo's coolant lines. They come in different sizes.

best wya to do it, match size to something already on the car, and simply put the turbo AFTER whatever you bridge.


But in reality, it doesnt matter. Just make sure you dont damage anything during installation, and use good quality clamps and connections. cheap clamps break if you have them too tight and things get hot, expand, and break them.
Thanks
Also, why would an IACV need coolant.....guess there's no harm in using that as a feed for the turbo?
why does it need coolant? it doesnt use it directly. The coolant removes ice build up that occurs in cold climates.
Ok , so I guess Ill try use the feed from the IACV line and drain to the water pipe.
the water pipe is pressure line isn't it....since its coming from the water pump.

water pipe > turbo coolant feed > port in block.

if you don't want to put a port in the block, you could return it to iacv or



or tap



not my pics @NeonPinHead





I bought this coolant kit from a member on here YEARS ago. feeds from the water pipe and follows the oil feed to the turbo, then drains back into the radiator hose









I have since bought a block port and will use that.....whenever I get my build done
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Thats really good information!!! So I know I have a shit ton of options but the source has to be from that water pipe which is going to be a pain in the ass to deal with. Any tips without removing the whole intake manifold off?
This is what I did. Your picture you attached, this smaller hose barb off the intake is part of a T that directs coolant to IAC and FITV components, as well as the main hose that leads to the heater core:

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This is warm pressurized outward flow, so that fitting will send coolant towards your turbo.

I ran a line from here to the fitting on the turbo that was the LOWEST coolant fitting. Because this water will be warm, convection tends to have this water flow towards a cooler source, and because heat rises, it makes sense to have the lower turbo fitting be the fitting that is the INLET to receive warm coolant.

The HIGHEST turbo coolant fitting should RETURN coolant back to the engine towards a cold source, and one which also is a DRAW towards the water pump, such as the lower rad hose using a fitting that Slo provided, or simply the nipple on the water pump supply pipe at the back of the engine:

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Once you know where the hoses will attach, routing direction and path will be your own choice:

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Technology Machine Space Automotive engine part Silver


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I also manually bleed this circuit with coolant using a handheld vacuum pump before starting the engine, to ensure all air is removed from the turbo coolant supply circuit.

I disconnect the hose at the intake T which leads to the turbo, fill radiator with coolant till coolant starts pouring out of it, then cap it with a rubber cap.

Then I hook up the vacuum pump to the hose that leads to the turbo and pump until coolant comes out.

This effectively draws coolant from the water pump return pipe hose, through the turbo, and out the hose that will attach to the T fitting nipple. Once I know coolant is coming out of this hose, I reattach it back to the intake nipple and hose clamp it.

Now you are guaranteed to have coolant inside the entire turbo coolant circuit before startup. Then bleed the rest of the engine normally after startup.
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This is what I did. Your picture you attached, this smaller hose barb off the intake is part of a T that directs coolant to IAC and FITV components, as well as the main hose that leads to the heater core:

View attachment 137567


This is warm pressurized outward flow, so that fitting will send coolant towards your turbo.

I ran a line from here to the fitting on the turbo that was the LOWEST coolant fitting. Because this water will be warm, convection tends to have this water flow towards a cooler source, and because heat rises, it makes sense to have the lower turbo fitting be the fitting that is the INLET to receive warm coolant.

The HIGHEST turbo coolant fitting should RETURN coolant back to the engine towards a cold source, and one which also is a DRAW towards the water pump, such as the lower rad hose using a fitting that Slo provided, or simply the nipple on the water pump supply pipe at the back of the engine:

View attachment 137568


Once you know where the hoses will attach, routing direction and path will be your own choice:

View attachment 137571

View attachment 137572

View attachment 137573
So if you dont mind, let me make sure that I understood everything..
For the feed, I could use essentially 'T' that small hose which has pressurised warm coolant and run one side of the 'T' to the lowest port of the turbo.

For the drain, I could just put a huge 'T' on the lower radiator hose which has the required size from the turbo drain fitting.

Does that sum up what you explained? And by that I wouldn't be messing with ths IACV coolant supply aswell(not that it needs it, but still)

Also this is slightly off topic but 440cc injectors and a 255 fuel pump would be enough for 200hp right?
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Dont bother "T'ing"

Just remove the nearest hose from the IACV, run a new hose from that to the turbo. Then run the turbo water outlet to where the IACV hose was going to.

You dont need to T, you simply need to have it inline.


Now, if you do NOT have an IACV and you have a FITV that relies on coolant temp to operate (no electronics) then it is mandatory that you get the coolant AFTER the FITV, so the FITV doesnt prematurely drop idle speed.

Grab some heat resistant jacket (or use a couple spark plug jackets for small block chevy) for where the hose is near the turbo and manifold.


The hose that goes into the cylinder head nearly dead center under the distributor is another good source to minimize hose length, but is LARGER than the IACV hoses. Check the size you require.
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So if you dont mind, let me make sure that I understood everything..
For the feed, I could use essentially 'T' that small hose which has pressurised warm coolant and run one side of the 'T' to the lowest port of the turbo.

For the drain, I could just put a huge 'T' on the lower radiator hose which has the required size from the turbo drain fitting.

Does that sum up what you explained? And by that I wouldn't be messing with ths IACV coolant supply aswell(not that it needs it, but still)

Also this is slightly off topic but 440cc injectors and a 255 fuel pump would be enough for 200hp right?
Pretty much (y)

Also yes:

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Hey, by any chance do any of you know the inside diameter of the lower rad hose?
@drtalon123 I have clocked the turbo and got all my parts in today. With the turbo clocked, the turbo inlet and outlet are both horizontal so there isnt any low point or high point. Does it matter how i hook it up if this is the case?

And also I just want to double check before I cut into any piping...
So ill feed the turbo through the the IACV and outlet into the bottom radiator hose. Does it matter where I put it on the radiator hose?

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@drtalon123 I have clocked the turbo and got all my parts in today. With the turbo clocked, the turbo inlet and outlet are both horizontal so there isnt any low point or high point. Does it matter how i hook it up if this is the case?

And also I just want to double check before I cut into any piping...
So ill feed the turbo through the the IACV and outlet into the bottom radiator hose. Does it matter where I put it on the radiator hose?
If there is no slope between the in/out ports, that's OK. Continue with plumbing as you mention, IACV outlet feeding turbo, then return to bottom rad hose.

No issues with lower rad hose position, any place within the length of the hose will do. This will get the turbo return to function as part of the water pump return loop, somewhat.

Going with the lower rad hose return method means full turbo coolant flow will be at the mercy of the thermostat opening and closing. Sure there is still a tiny amount of flow when it's closed from the jiggler on the t-stat, but full flow will only really happen when tstat opens at operating temp.

This was the only reason I plumbed my turbo return into that nipple in the middle of the waterpipe. This place always has full unrestricted return flow since it is behind the tstat. Yours will simply be in front of it, and full flow will have to wait till it opens at roughly 190F/85C. Lots of people put it there, so I'm sure it's fine.
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Sounds good to me, Ill send some pics of the plumbing so that others may want to use this methods.
Thanks again friend
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