Pump Fitment
Next step was the pump.
Before you do anything, attach the pump to a 12v supply
(run it off your car battery if you want) and make sure it works.
The worst thing you could do is get to the point of bleeding the system to discover that it doesn't
(as I did).
The pump connector has 2 larger pins and 3 smaller ones
- the 2 larger ones are the
+ve and
-ve for the pump.
If the pump doesn't work, remove the 3 bolts around the inlet to gain access to the impellor chamber.
If the pump works with the top off, then there is crap in the top cap preventing the impellor from spinning
- wash it out and reattach.
If the pump is noisy, replace the bearings.
There is a guide on gtfours.co.uk but I can't link to it directly.
Once you're happy with the pump, move on.
I'd spotted 2 mounting points on the gearbox which I figured were the right place for it.
The pump in question, complete with the mounting bracket from the Celica:
The bolt nearest my thumb needs to come out as that back bracket fouls on the gearbox:
These are the mounting holes I found on the gearbox:
Pump fitted
(with 2 x CC Pump Bolt
- T90105-10393):
The pump must go in this kind of orientation.
It has a drainage hose on it for water to drain out of it like most of the components in the engine bay, and this must point at the road.
It also makes the system much easier to bleed if the pump is the lowest point.
For reference, the left hand pipe in this image is
*in* and the right hand one is
*out*.
I have had the pump attached to my car for over 6 months now and it's not even got a scratch on it.
It is not the lowest point of my car
- my sideskirts, exhaust flexi and front bumper are all lower.
Your mileage may vary!
Grab the hose that runs down the passenger side of the car
(the one you covered in tape), and cut it to a suitable length to reach the pump.
Be very careful here because if you get it wrong you'll need to get another joiner and more clips to extend it.
Also remember that the pump is mounted to the gearbox, and the gearbox moves! Attach the pipe to the pump's outlet
(passenger side) and jubilee clip it.
I used a silicon straight reducer, 22mm-19mm here to make life easier.
It provides plenty of flexibility and made for a lot less messing around underneath the car.
Without it you'll struggle to get the 19mm hose onto the 22mm pump outlet
(and you might damage the pump in the process).
Once you've done that pull the hose you cut down a bit and attach it to the pump's inlet
(driver's side on the pump) and secure it.
I used a 22mm-19mm silicon reducer here, this time a 90 degree angled one.
GT4 Engine Hanger
This stage is optional, and tbh I'm still not sure it was worth doing.
However I had as stated intended for the chargecooler to be fitted the Toyota way so if you've bought the GT4 Engine Hoist Hook
(Part no.
T12281-88480) then this is what you need to do:
First off, here's the engine bay.
There are some pipes that aren't original:
Aircon Idle Up
- Yellow
Dump Valve Recirc Pipe
- Clear w/white bits
Dump Valve Manifold Pressure
- Clear
Throttle Body Carbon Canister Pipes
- Blue
Click for bigness.
Highlighted are the pipes you'll need to detach to get to the engine hanger.
You only need to remove them at the ends indicated, and while order's not important, the numbers indicate the order in which I removed them.
1.
Aircon Idle Up.
This is an important one to pay attention to, as it is replaced as part of the core installation.
It doesn't exist on Rev1 or Rev2 engines, I'm not sure how they deal with that bit.
This goes into a hard pipe by the end of the engine
- the other end of this hard pipe is
#6.
2.
Dump Valve Manifold Pressure
- This also goes into a hard pipe and runs round to the side of the inlet manifold.
The other end of this is
#9.
3.
Another hard pipe, other end of this is 10.
This is just an engine breather.
4.
Catch Can Outlet
- This just returns air from the crankcase once the oil vapour has cooled and turned back into oil in the catch can
(big black box next to it).
5.
Catch Can Inlet
- Breather from the engine into the catch can.
There's another smaller pipe going into the catch can underneath this
- take that off too.
6.
This is just the other end of the aircon idle up, take it off the hard pipe.
7
& 8 don't have to be removed, I just found it easier with them out of the way.
They can be tucked up round the engine bay lock, but don't close the engine lid if you do this
9.
Other end of
#1.
10.
Other end of
#3.
Once you've got all of them off, you can remove the catch can and its bracket, with the 2 hard pipes for
#1/#9 and
#3/#10.
This is only held on with one bolt
(14mm), in the location indicated:
That lot can now be lifted out and put to one side.
If you've got a bit of an unhealthy engine your catch can might be full of oil, so be careful with it.
Mine had no oil in it.
.
.
You may find it easier if you unplug some of the HT leads from the distributor
- make sure you put them back in the right order!
Now you can get the existing engine hanger off.
It's held in place with 3 bolts, as indicated.
The 2 indicated with the arrow are on the boot-side of the head, and have a coolant line or 2 directly next to them, which means you can't get a socket on them.
These are done up incredibly tightly
(as you would expect for a bracket designed for hoisting the engine out) and I had to use 2 spanners linked together to get enough leverage to get them off.
Obviously getting a socket onto the left hand bolt is easy.
All 3 are 14mm.
Here's the 2 engine hangers next to each other.
As you can see there are obvious similarities between the two, but the GT4 one is much larger.
I have a sneaky suspicion that the engine hanger hook on the MR2 one might have snagged on the core if it had stayed in.
Unfortunately the GT4 one won't fit without a bit of modification
- and the bit that needs to come off is one of the chargecooler core mounts
However it won't fit around the MR2's coolant neck, so it has to go.
It still leaves 1 mount and they look pretty tough.
I sawed the mount off mine, and afterwards it looked like this:
Once that's done you can throw it in the engine bay and bolt it in place.
It looks like this once it's installed:
Now that the GT4 hanger is in place, the hard pipes attached to the catch can need a slight mod to go back in.
I'm still not totally sold on this as it's repositioned the catch can so it might need a bit more work to accomodate the chargecooler core.
All you need to do is take the bit to the right of the bolt hole off the end as it snags
- as you can see from this photo I had already started sawing it off.
I found it much easier to do this having unclipped the catch can
- it's just clipped in on either end:
It would be nice if we could just use the GT4's catch can bracket here but unfortunately the pipes all route completely differently.
Once it's back in it all looks a bit like this:
You can now reconnect the pipes you removed at the start, and sit back and wonder whether you've actually achieved anything.
Important note: Do not reconnect the aircon idle up
(yellow pipe in my pics) if you're installing the core at this time.
For a start you'll have nothing to connect it to as the hard pipe was part of the engine hanger.
Secondly it goes somewhere else later on.
However if
(like me) you are doing this in stages and need the car running inbetween, you can easily unbolt the hard pipe from the MR2's engine hanger and reconnect the pipe.
Core Modification
While the chargecooler core is from the same engine, the coolant layout in the Celica is a lot more.
.
.
conventional as the engine and radiator are in the same place
As a result the coolant neck on the side of the MR2's engine is very different, and fouls on the MR2's coolant neck, as per this picture:
There are a few options available to you here.
I know Allan cut the pipe off the core and welded it back on at a different angle.
I can't weld and don't have access to a welder, so I have cut it off.
In fact, I cut it almost all the way back to the core, so that there was only about 30mm of the pipe protruding from the core.
I did the same with the other outlet too, because while it doesn't catch on anything, it just makes the installation a whole lot more flexible.
Remember, you will need to move the core in order to service your car
(sparks, leads etc) so flexibility is a good thing! These pipes were replaced with 90 degree silicon reducers, again 22mm-19mm to get the pipe size down to match the hose that runs under the car.
You should also remove the mount on the core that's nearest the engine coolant neck.
We already removed the point it connects to on the GT4 engine hanger, and it will only rub on the coolant neck if we leave it there.
Think of all the saved weight
Core Installation
Time to install all of those Celica engine parts! Here's a photo showing the MR2 and Celica throttle body parts next to each other for comparison:
Top ones are from the MR2 engine, bottom ones are the new Celica parts to go on.
The bolts outlined in red
(part no T90105-08286) are actually the same on the MR2 as the Celica, so they can be reused.
This is the engine bay as I started:
First thing to do is to disconnect the accelerator cable.
Take it off the throttlebody first, by pulling the sprung semicircle bracket towards the cabin, and unhooking the cable.
With that disconnected, you can remove it from the MR2's accelerator bracket.
Slacken off the nut nearest the cabin and you should be able to pull it out of the bracket.
Mine has a clip on a jubilee clip on the turbo
-> intercooler hardpipe too, take it out of that.
Now remove the pipe going between the throttle body and the intercooler.
The previous owner of my car was obviously a bit paranoid as this was held on throttlebody end with 3 jubilee clips! The silicon joins should have enough slack in them for you to be able to pull the pipe off without too much trouble.
This then affords you access to the throttlebody etc.
You can take off the one that goes from the turbo hard pipe to the intercooler as well.
Undo the 4 14mm bolts holding this long cylindrical part on.
Now you can take off the intake support bracket.
It's held on with 2 long bolts going into the cylinder head, and 2 shorter ones going into the throttlebody.
Again, these are 14mm.
Watch out for the tiny rubber gasket underneath
- this needs to stay where it is.
Throttlebody should now look like this!
You should now attach the Celica intake support bracket.
If you bought a new one remember to take the label off the back of it
It does exactly the same job as the MR2's one, but doesn't surround the throttle intake.
The 2 long bolts with washers on
(T90119-08870) go into the throttlebody itself, and you can reuse the 2 bolts that went into the head.
Next up is the throttle sock.
Using the 4 bolts
(T91511-B0825) first attach the 2 passenger side.
On the driver's side you should attach the Celica accelerator bracket on top of the throttle sock
- don't put it inbetween the throttle sock and the throttlebody.
All together it should now look like this:
Congratulations, you've converted your throttle assembley into a Celica one! It sits a lot further back towards the boot than the MR2 one did, which gives us enough space to fit the chargecooler core on.
Now we need to get this pipe off:
Undo the 4 12mm bolts on the bracket that attaches this pipe to the head, and ditch the bracket.
If they're not still disconnected from you fitting the Celica engine hanger, or if you've since reconnected them, you should disconnect the air con idle-up pipe, and the dump valve manifold pressure pipe.
These are the small pipes that run from the dump valve down the side of the engine, and from the intercooler hardpipe down the side of the engine.
They're identified on a pic earlier in the guide.
You should also disconnect the dump valve recirc pipe too.
With all this disconnected you should be able to slacken off the jubilee clips attaching this pipe to the turbo and pull it off.
Your engine should now look like this:
Now you can drop the core into place.
I found it a little complicated to get the pipes and hoses all attached as the passenger side of the engine bay is an absolute mess! You want to get the pipe that exits the core directly underneath the filler cap attached to the pipe coming up from the pump.
That's the one with the tape on.
It was a lot easier if the pipes exiting the chargecooler
(remember I'd replaced these with silicon reducers) were crossed over in an X as that made them occupy the least amount of space.
One of them had to run underneath the ICV hose and one over the top.
The previous owner of my core had heatwrapped the underside.
I deemed this as a good thing and was not going to remove it.
However it did mean that the core didn't fit down nicely onto the head, even after removing the plastic jacket that the HT leads are held in.
It also meant that the bolt to attach the core to the head didn't reach, and the pipe attaching the core to the turbo wasn't a great match either
- I replaced the hose at this point with one of the ones that had attached to my intercooler which was about 20mm longer.
This overcame that problem nicely.
The core still bolted down to the GT4 engine hanger as you would expect.
The next pain was the dump valve.
I used the hose from the turbo hard pipe
-> aircon idle up as well as some 3mm vacuum hosing I had lying around to lengthen the smaller pipes coming off the dump valve to the
't' piece.
This then allowed the exit from the
't' piece to reach the existing piping nicely.
I cut down the hose I had used to replace my recirc hose to about half its length and used this to reattach the outlet from the core to the inlet on the dump valve.
This results in the outlet from the dump valve pointing downwards
- I could reconnect this to the induction kit but it's really not worth the effort.
I blocked up the hole that was left in the induction kit.
Wiring
As I've already mentioned, I intend to use a Celica ECU to perform pump control logic.
I've looked into this a bit more, and the Celica ECU has the chargecooler pump circuit
instead of the engine bay fan one.
However this is a bit irrelevant because the cooling fan output from the engine ECU is an emergency override anyway, the fan retains its own ECU for normal usage.
Important Note I found that with the core installed and retaining the MR2 ECU, the engine bay fan took a very very long time to kick in.
I presume this is because the top of the core remains cold at all times, and the engine bay temp sensor is directly above it.
I unplugged the sensor, and allowed the fan to run all the time.
If you were lucky
(like me) your chargecooler pump came with both side of the wiring connector.
You'll need to extend whatever wiring is left on this connector to run back into the boot.
There are a few points to be aware of when doing car wiring:
Always use heatshrink
(and always use the RIGHT SIZE heatshrink).
It's waterproof when used correctly!
Never run wires on anything hot
(gearbox, metal coolant pipes etc)
Never leave any bare wiring exposed
Always solder, no scotchlocks!!
Disconnect the car battery, and the ECU while doing this work.
Whenever your wiring reaches its destination or travels through a bulkhead
(yours will do both) you should take the wiring lower than it needs to be and loop back up to whatever it is you're connecting to.
This will mean that any water running down it will drip off the bottom of this loop, rather than into your pump, into your boot, into your ECU etc.
The wiring process differs massively depending what you want to monitor.
You can, for example, wire in a warning light for when the pump's failed.
You can wire in a level sensor.
You can replace the level sensor with a temperature sensor and wire that in to something.
I'm only going to cover the most basic wiring required to get the pump running on the ignition.
You should push 2 wires through from the grommet next to the ECU.
It's in the boot, behind the carpet on the bulkhead.
You can push straight through the middle of the grommet.
You should use wire that's capable of
~15A, just to be on the safe side.
You'll need to push through from the boot side as you won't be able to get to that grommet from the engine bay side
- the fuse box is in the way.
I chose to cabletie my wiring loom to the coolant pipe that ran from the chargecooler core down to the pump.
You'll be installing a relay in the boot
- you should use one rated at 10A or higher.
The one I used had an integral fuse
- if yours doesn't you should use an inline fuse holder where you connect within the fusebox.
Attach one of the wires that you pushed through the grommet to pin 87 of your relay.
Attach the other end of this wire to one of the screws underneath the large red rubber cap in the engine bay fusebox.
You can get the wire into the fusebox from underneath.
Take the 2nd wire you pushed through, run it down to the pump, and attach that to the
+ve pin on the pump connector.
Connect the other end of this wire to pin 30 on your relay.
Make up a small cable to run from the
-ve pin on the pump to a suitable grounding point
- any old bit of the chassis should do).
Connect pin 85 of the relay to the
<something> pin of the ECU.
Connect pin 86 of the relay to something that will ground to switch the pump on.
I connected it to ground all the time
(as the
+ve is coming from the ECU which is only powered when the ignition is on).
<Many pics required here>
Hey presto! Reconnect the ECU
+ battery, turn the key in the ignition
(don't start the engine) and stick your head down by the passenger side rear wheel and you should be able to hear the pump whirring.
Don't leave it like this for long, the pump's not designed to run with air in it.
Bleeding the system
I found bleeding the CC quite difficult, but not as difficult as some people had told me it would be
The radiator end is very straight forward.
Take the hose you attached to the bleed nipple and hold it upright
- a good way of doing this is to tape it to the bonnet.
It only needs to be higher up than the chargecooler core is.
Next up, pour coolant into the core.
Do this slowly, you'll see lots of air bubbles as you go and the level will slowly drop.
Keep doing this until it stops dropping.
Massage the outlet pipe a bit and more air bubbles will appear, and the level will drop.
Keep going until the level stops dropping.
Go round to the front of the car, and suck on the pipe attached to the bleed nipple.
This will help draw the liquid through from the core.
You'll only need to suck a little bit
(you don't want to empty the core as that will introduce an air lock), then run back round to the engine bay and pour more coolant in.
Repeat until you start seeing coolant in the pipe that's attached to the radiator.
Don't get any coolant in your mouth, it's poisonous
Now click the ignition on so that the pump is running.
You should now be able to keep pouring coolant in at a reasonably steady rate
- if the core backs up and it looks like the coolant isn't flowing well then massage the pipes again to get air out.
Occasionally you might need to run round to the front again to draw a little more air out of the radiator.
You'll know when you're done because you get a whirlpool effect in the filler hole.
At this point, put the filler cap on one click and block up the radiator bleed hose with a suitably sized bolt
(I used 2 cable ties as well to be sure).
Take the car out for a drive.
The process of sloshing the coolant around while driving up and down hills and warming it up a little will help to get more air out.
DON'T drive for too long, just enough to warm the engine up, and DON'T use any boost! If you get any funny noises, blow any hoses off that you haven't connected up properly, etc etc then STOP IMMEDIATELY.
If all is good then you should be able to pour quite a bit more coolant into the system
- don't worry about letting it cool down before you take the cap off as it won't have got hot enough to spurt out all over your face.
Check underneath your car once it's cooled down to make sure nothing's leaking.
Repeat this process 3 or 4 times and you should be more or less air free.
You should check the level daily for the first fortnight as you would when bleeding the main coolant system as more and more air will work out.
Job done
