Hill climb and cooling issues.

[pureadrenalin]

Did a local Taranaki car club hill climb on the weekend, Kirihau road. Santasboostinsleigh came out for a spin in the car. What sunny hot weather it was, so hot in fact, that the fourth run that we were going to have got canned, as the chip seal was getting a little ripped up.

http://nz.youtube.com/watch?v=vaOrlZuXNKg

I’m still not happy with the cooling capacity of my car at the moment. The hill climb doesn’t test the car as its too short, but the track stuff I do does.
The bottom of the radiator is stone cold, gradually getting hotter towards the top. The inlet and outlet to the radiator are both at the top, and it seams that the hot water is just running across the top of the radiator.

Anyone with an MR2, after a drive, can you put your hand on your radiator and see if the fins at the bottom of your radiator are much cooler than the top.
Is this just me having radiator issues??

[Mr Revhead]

is the car over heating?

i found with mine (aw11) that the cooling capacity was good enough that the fans never needed to kick in

[B1NZ]

Put the engine in the front where its supposed to be and shorten your radiator hoses

[Crampy]

My S/C AW11 used to get a little hot when giving it a good hiding.

The air con was stuffed on it, so I pulled out the heat exchanger. It's in front of the radiator and when removed made the car run a lot better temp-wise.

[Mr Revhead]

i put the intercooler heat exchanger right in front of my rad

[Crampy]

I always wondered how much better my car would have gone with the water to air intercooler I bought for it. Never got around to it and ended up selling the car

[mr30%jr]

marginally different on S/C

AW11 and SW20 should in no way be getting hot!

also im pretty sure the outlet on the side tank is at the bottom of the rad. and inlet at the top.

youd need to put a temp gauge on the return water hose near the engine. it would sound to me you have some restriction or the thermostats an issue

ps. yes there stone cold at the bottom. heat rises.

[pureadrenalin]

is the car over heating?

Yes. Not on hill climbs tho, on the track where the races are a little longer.

It has no A/C radiator, so no restriction to cooling there.

AW11 and SW20 should in no way be getting hot!

also im pretty sure the outlet on the side tank is at the bottom of the rad. and inlet at the top.

youd need to put a temp gauge on the return water hose near the engine. it would sound to me you have some restriction or the thermostats an issue

ps. yes there stone cold at the bottom. heat rises.

I know it shouldn't be getting hot, last race meet at manfield was the first time I've overheated it.
Inlet and outlet are both on the top as in the pic below:

http://carpron.com/multisite/d/347856-2 ... OR_OLD.JPG

I have a temp gauge, this is how I know things are bad.
New thermostat, water pump, lines checked to see if they were blocked, end tanks off the radiator and fins cleaned.

The next step I'm going to is adding another inlet and outlet to the radiator on the bottom in the sketch below:

[Truenotch]

Tried taking it to a radiator place to have the tanks taken off for a service? Even a 15% blockage makes a big difference, and since both inlet and outlet are at the top it's pretty feasible that there would be crap clogging up the bottom of the rad.

Still got the heater core setup?

[postfach]

I don't think you need to add extra inlets/outlets, but you should change the outlet to the bottom, having them both at the top is weird...

Being a crossflow radiator it should perform well, but ideally the inlet and outlet should be as far away from each other as possible to be as efficient as possible.

If it's not brand new, have it cleaned, too (but not just the radiator, get your entire cooling system flushed by a radiator place).

[mr30%jr]

this is sw20?

[pureadrenalin]

Yep, it’s an SW20.



The radiator had the end tanks taken off, and the tubes cleaned out last week. Entire cooling system (apart from the block) has been inspected. Pump and thermostat replaced.

Heater core setup? As in passenger compartment heating? Yep, still have that installed. Yes I follow the BGB when bleeding the system.

The mods to the radiator to add an inlet and outlet is being done as we type. I just need to modify the supply and return lines after work this week.
The next round of racing is this weekend at Pukekohe on Sunday. 3 x ~10min races followed by a one hour enduro.

I overheated it at manfield in all three ~10min races (on the cool down lap), which is why I’m going to this extent to try and be able to complete the one hour race.

[fivebob]

Inlet and outlet are both on the top as in the pic below:

http://carpron.com/multisite/d/347856-2 ... OR_OLD.JPG

So you are not running a standard SW20 radiator then?

The standard SW20 radiator has inlet at the top passengers side, outlet at the bottom drivers side, and, apart from when it's not bled properly, it is not known to be an issue, even on 600HP+ cars.

Perhaps fitting a standard radiator might be your best option

[pureadrenalin]

It IS the standard radiator, even the second one I’ve had in the car because I crushed the first one on a plastic water filled barrier.

The outlets are both at the top.
The metal pipes circled in red come up from under the car from the lines circled in green, go through the front wall, and connect to the top of the radiator at the blue circle on either side of the radiator.

http://carpron.com/multisite/d/348355-1 ... IRCLES.JPG

Sorry I haven’t got any pics of my radiator out of the car to see the outlets.

Funny, when I search on google, the only MR2 radiators I can find have the inlet/outlet staggered like the pic below:

http://www.desicodesign.com/meerkat/images/radiator.jpg

On my STANDARD radiator, the vent on the left top is off the top of the radiator, not the back like shown, and that is where the inlet pipe is.

[mr30%jr]

yes he is running a standard sw20 rad, i thought he had a aw11 which is different...

maybe you could look at running and aw11 one.. the reason its like that is the sw20 water pipes head through the frunk intead of like aw11 which is under the car.

http://img244.imageshack.us/img244/9035/sw20radns5.jpg

the image in the above post to mine is aw11 you can tell via the fans and there no water temp sensor

[pureadrenalin]

LOL

That’s three different configurations that three of us are talking about.

So;
AW11 is “inlet bottom left, outlet top right”
SW20 is “inlet top left, outlet top right”

What radiator do you have fivebob, that has “inlet top left, outlet bottom right”?

WTF are Toyota trying to do to us!

[fivebob]

What radiator do you have fivebob, that has “inlet top left, outlet bottom right”?

oops my bad

Been so long since I looked at one I got the pipes confused with the bleed & drain taps, goes to show you shouldn't rely on memory

Anyway, I can't see how you will get a benefit from moving the outlet pipe, the end tanks are on the sides of the radiator, so the water must pass through the radiator to get from inlet to outlet.

That being the case then you have several possibilities.

1. Faulty Thermostat. Unlikely but possible.
2. Blown Head Gasket.
3. System not properly bled.

I'd guess #3 would be the most likely. Even though you say you used the BGB bleeding procedure I've found that is often not enough to get all the air out. What I do is to bleed as per BGB, then jack the rear up as high as it will go and run the car at idle with the radiator cap just loosely on topping the coolant up every few minutes until no more air comes out. Then allow it cool down and top up again.

[Leon]

On an unrelated to radiator note... Damn that sprint looks like fun!! Narrow, windy bastard roads. Great

[Truenotch]

AW11 is “inlet bottom left, outlet top right”

Inlet top right, outlet bottom left < from the driver seat. Hot side has the high inlet, cold side is low outlet.

[pureadrenalin]

Hey Leon, on the right after the second corner there is a $200k R33 GTR parked down the bank, you can’t see it in the video, its hidden by the grasses.

I got the radiator back last night. Looks like they did a really good job adding the new inlet/outlet. Small pic below to show what we’ve done. Inlet in red, outlet in blue.



Now I just need to get the supply and return lines modified to something like what is shown in that pic.
What a pain to get them out tho, had to take the battery box out, brake lines out of the slave cylinder.

Also last night with a bit of help from others we got the brackets made up to hold the fans on the oil cooler, started making the ducting for the front brakes, and got the front bumper fixed from braking it last weekend.

Still so much to do before this weekends racing.