Car getting warm.... what am I missing?

Hi all

So long story short the supra started to leak a little bit of coolant a few weeks back which looked to be coming from the front of the water pump around the pulley area. After having cooling problems many moons ago on my old NA and chasing my tail I decided this time to go all out, and I bought new for most parts. OEM Thermostat, oem lower rad pipe, mishimoto rad, srd overflow tank, wifbitz top hard pipe, and new OEM water pump along with all necessary OEM gaskets where purchased.

The other week I got a bit bored and decided to start doing some of the bits myself, and went ahead and fitted the radiator and overflow tank. Now when trying to bleed the system with new coolant, (with the front jacked up, AC on, and rad cap off) The car just continued to get warmer and warmer. I let the OEM temp gauge get 3/4 of the way before stopping. The top rad pipe was warm and the bottom was still stone cold, I gathered this meant the thermostat had given up.

So this leads me to today. I have just fitted the new OEM thermostat, thermostat O-ring, and OEM rad lower pipe. When attempting to bleed the system I'm having exactly the same issue. Very annoying as this is holding me up getting the car booked in for the water pump and cam belt done as I cant drive it.

What does everyone think? Could the water pump have stopped functioning all together? If its not this what else could it be or am I doing something stupid?

It appears that you have mended everything that wasn't broken, fitted a radiator that needs to be removed and have an air lock in the cooling system.

Some say, jacking up the front will clear it.

Leaking coolant and warming up for no reason sounds like headgasket. You won't necessarily see the "mayo" everyone describes. If the gasket has perforated around a cylinder you might find it has a tiny blow by and exhaust gases are heating the water and causing pressure and heat in your system. How many miles has the car got? What age is it? Unopened engine?

It appears that you have mended everything that wasn't broken, fitted a radiator that needs to be removed and have an air lock in the cooling system.

 

Some say, jacking up the front will clear it.

Yeah was wondering weather or not it could be a airlock, any advice on how to try remove it if that is the issue?

Leaking coolant and warming up for no reason sounds like headgasket. You won't necessarily see the "mayo" everyone describes. If the gasket has perforated around a cylinder you might find it has a tiny blow by and exhaust gases are heating the water and causing pressure and heat in your system. How many miles has the car got? What age is it? Unopened engine?

Will see, have contacted Lee, and as a precaution I will get it tested for HC's. Car has 80ishk and yes and unopened engine. seems starnge that the only issue before the rad change was the leak so seems unlikely in my head. But will bare it in mind for sure

I agree with my learned friends in this thread, although I have no opinion about what was causing the coolant leak. Could be headgasket, could be water pump I suppose, or perhaps one of several other things. Hard to say without seeing it.

If it wasn't overheating before, it seems unlikely that a mechanical failure like thermostat failure has caused it. It sounds very much like an airlock. When changing coolant, I park my car on a slope nose-up, turn the heater on full heat (and some say fan on full speed, I can't remember what difference this makes though), then fill the radiator quite slowly. Give the hoses a nice squeeze occasionally. Start the car when the rad is almost full. Let it idle, keep squeezing the top hose occasionally. Rev the car a bit for a few seconds. Be patient. Not sure if you've already done this, so I thought I'd put it here in case you haven't.

Yeah was wondering weather or not it could be a airlock, any advice on how to try remove it if that is the issue?

Did you forget to read the second sentence of my post?

Just to add to this my heaters are now stone cold and as they were brilliant before hand Im guessing this leads to an air lock?!

I agree with my learned friends in this thread, although I have no opinion about what was causing the coolant leak. Could be headgasket, could be water pump I suppose, or perhaps one of several other things. Hard to say without seeing it.

 

If it wasn't overheating before, it seems unlikely that a mechanical failure like thermostat failure has caused it. It sounds very much like an airlock. When changing coolant, I park my car on a slope nose-up, turn the heater on full heat (and some say fan on full speed, I can't remember what difference this makes though), then fill the radiator quite slowly. Give the hoses a nice squeeze occasionally. Start the car when the rad is almost full. Let it idle, keep squeezing the top hose occasionally. Rev the car a bit for a few seconds. Be patient. Not sure if you've already done this, so I thought I'd put it here in case you haven't.

Thanks this is pretty much the method i am using.

Did you forget to read the second sentence of my post?

I did indeed as said in my first post though I have the front end jacked up already.

I find rather than leave the rad cap off the whole time, put the cap on and let the system build up a bit of pressure, then remove it (obviously dont leave it on too long so that it blows out into your face lol)

I find rather than leave the rad cap off the whole time, put the cap on and let the system build up a bit of pressure, then remove it (obviously dont leave it on too long so that it blows out into your face lol)

As a matter of fact thats what I did, and the temperature is staying great now! had to build the revs at one point then all of a sudden she coughed and the heaters went warm!

Just need to re-fit some more bits then I can go test it on the road tomorrow.

You're a worrying man when you have a spanner in your hand.

You're a worrying man when you have a spanner in your hand.

Indeed I am, will happily admit that, its not in my comfort zone. Now shiny stuff I can do!