EJ20T cooling curcuit

1303Steve · Posted: Fri Oct 19, 2012 11:38 am Post subject: EJ20T cooling curcuit

Hi

After driving my car around a bit I got to thinking if I've done the correct thing with cooling lines from the turbo and to the thermostat housing, its not over heating and warms up quickly.

I teed the coolant line from the turbo and going to the thermostat and ran them to my T3/Vanagon/T25 header tank.

I was wondering if I should just join the original coolant lines between the turbo and thermostat. On the Subaru they both attach to the stock header tank on the intake manifold.

I've searched for pictures or any word on how others have done this on here and other conversion sites and I've not found the answer.

Steve

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STI powered 1303 now running
G50 box, Boxster/944 brakes, Adaptronic 1280E ecu, PWR intercooler etc

Kai · Posted: Sat Oct 20, 2012 7:26 am Post subject:

Your join is it T'd then going to the header tank?

I removed the Subaru header tank and joined the pipe at the top to the pipe at the bottom effectively bypassing it with a new longer one piece pipe. So it basically goes out of the turbo and into the water pump pipe.

Turbo outlet

Goes here to waterpump pipe next to the right hand cylinder head/Inlet port, it's additional on the turbo's water pump compared to the NA.

Originally the turbo went into the top of the header tank (non fingered) and out of the bottom (fingered). I've simply bypassed and removed the header tank.

Now for a header tank my system is a total rip off of Elusive Strangers design. I copied his design as its a proven design and I'm not one for reinventing the wheel. I get the impression people fear turbo conversion trying to accomodate for the turbo which in its essence is very easy to cater for.

To fit the header tank

RJES water manifold

Into the top of the header tank

Out from the bottom of the header tank

And into the thermostat pipe where Subaru heater used to be.

This design has always been a reliable design and totally self bleeding.

However.....

I've now installed a heater between the header tank outlet and the thermostat pipe. This is where my system gets annoying as I need to put an air bleed near the heater as it'll now cause an airlock. All I have to do though is fill the system in my driveway which is a steep downhill and then drive it to knock the air out.

The airlock sounds worse when ive typed it out on here then it actually is in reality and now that I'm thinking about it, it would not be a difficult task to have a small bleeder outlet T'd into my radiator bleed pipe as they are close together.
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Think......

Don't sleep and drive!!!

1303Steve · Posted: Sat Oct 20, 2012 12:10 pm Post subject:

Hi Kai

Thanks for that I'm much more confident now to join these two hoses now.

At the moment my T25 header tank never fills up completely, I used the same header tank on a WBX powered Beetle it always filled completely from the overflow after a few warm up & cool down cycles.

Steve
_________________
STI powered 1303 now running
G50 box, Boxster/944 brakes, Adaptronic 1280E ecu, PWR intercooler etc

Kai · Posted: Sat Oct 20, 2012 2:08 pm Post subject:

to put the science into the mix just to totally convince you the OE Subaru header has the top port as the supply and the bottom as the exit. You'd simply be skipping the Subaru header tank out of the system at this point. They have to put the header tank somewhere and that's where they chose to put it. Sticking it somewhere else shouldn't effect it's performance. What would effect it is by cocking up the flow of the circuit.
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Think......

Don't sleep and drive!!!

1303Steve · Posted: Wed Oct 24, 2012 12:02 am Post subject:

Hi Kai

I finally got a chance to drive the car after reconfiguring the hoses, its running about 5-10 degrees Celsius cooler and the cooling fan hardly comes on now.

I think the thermostat must be getting a hotter flow now making it open sooner and maybe wider.

I thought teeing the hoses would mimic stock Subaru header tank, I was wrong.

Thanks for taking the time to answer my question.

Steve
_________________
STI powered 1303 now running
G50 box, Boxster/944 brakes, Adaptronic 1280E ecu, PWR intercooler etc

Kai · Posted: Wed Oct 24, 2012 8:27 am Post subject:

Steve I'm glad I could help. I guess that I've always taken my system for granted as its always worked, been easy to bleed and my temperature gauge has always stuck straight bang in the middle. I've never actually measured the temperatures it's running at I've just used at VDO gauge on it. This is no doubt because its just always worked for me.

This was all before the heater install Happy

But I know what I've got to do to perfect that which is to simply add an air bleed valve to the heater which I'll do with a tee piece as I'm going to reroute the hoses to keep them out of the way of the pedals.
_________________
Think......

Don't sleep and drive!!!

1303Steve · Posted: Wed Oct 24, 2012 8:39 am Post subject:

Hi Kai

My system bled OK, but after running the car I would get slurping noise coming from the system after shut down, it doesn't make any noise now.

I unsuccessfully tried running the heater using a 4 way heater tap. I might give it another go now. It's coming into summer now so I going to concentrate on the air con 1st.

Steve
_________________
STI powered 1303 now running
G50 box, Boxster/944 brakes, Adaptronic 1280E ecu, PWR intercooler etc

panel · Posted: Sun Nov 04, 2012 7:54 am Post subject:

Can someone post that Elusive Stranger circuit here? Not to high jack but for others to see.(and me)
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EJ20 Turbo bus build

1303Steve · Posted: Wed Apr 09, 2014 3:21 am Post subject:

Hi

My system has been working pretty well I thought until I started doing a few speed events.

After about 4 or 5 minutes of full boost & full throttle driving on a race track my motor started to get a lot warmer than it usually does even on the hottest days in summer when driving fast on a freeway or stuck in traffic, around about 105 c.

I'm working on getting better airflow to my radiator, hopefully that will cure the problem.

Talking on another forum AVD it was suggested to not have the turbo outlet water going down to the thermostat and plumb it straight into the radiator water going to the radiator.

To do this I could plumb the turbo water outlet into my T25 coolant bottle but then I would need to block off the line going down to the thermostat.

Does anyone have any thoughts on this?

Steve
_________________
STI powered 1303 now running
G50 box, Boxster/944 brakes, Adaptronic 1280E ecu, PWR intercooler etc

panel · Posted: Wed Jul 04, 2018 4:16 am Post subject:

Bump......for what expansion/header tank you guys are using and does this system require an additional overflow tank ?

Also , is there still a small hose running from the rad to the expansion/header tank ?

1303Steve · Posted: Wed Jul 04, 2018 5:19 am Post subject:

Hi

Im using a Vanagon header tank and I run an overflow off that.

My radiator is too far away to run run a line to.

On another note I found that my dump was heating my coolant line when I was really getting into it on a race track, a bit exhaust wrap fixed that.

Steve
_________________
STI powered 1303 now running
G50 box, Boxster/944 brakes, Adaptronic 1280E ecu, PWR intercooler etc

1303Steve · Posted: Wed Jul 04, 2018 5:20 am Post subject:

Hi

Im using a Vanagon header tank and I run an overflow off that.

My radiator is too far away to run run a line to.

On another note I found that my dump was heating my coolant line when I was really getting into it on a race track, a bit exhaust wrap fixed that.

Steve
_________________
STI powered 1303 now running
G50 box, Boxster/944 brakes, Adaptronic 1280E ecu, PWR intercooler etc