My MR2, Knuckles61

[knuckles61]

Quick question, how do I tell the difference between Toyota coolant Mixing with the green coolant vs green coolant and oil? It's rusty coloured kinda and there is a pricipitate in the liquid. I've kept a good eye on the thermometer and it never went up past the usual spot of just under half way.
Thanks

[knuckles61]

Quick question, how do I tell the difference between Toyota coolant Mixing with the green coolant vs green coolant and oil? It's rusty coloured kinda and there is a pricipitate in the liquid. I've kept a good eye on the thermometer and it never went up past the usual spot of just under half way.
Thanks

[JasonFriday13]

Toyota red coolant and green coolant should never be mixed because they are made up of different chemicals. Can't really help beyond that.

[knuckles61]

Okay small update, took it to the garage to have the brakes inspected, rear pads were new and didn't appear to be seized on. The handbrake was adjusted from underneath the car, made the handbrake nice and tight again. No more fear of hill starts!

Regarding the coolant stuff he didn't think it was a head gasket problem since it ran fine without any issues and suspected it was just stuff left over from when the radiator was replaced (looks pretty new). So I will start to empty out the radiator and refilling periodically it with a recommended coolant, after 3 or 4 cycles most of the gunk should be gone hopefully. I will look to see if I can get a manual and flush it out properly but I think my limited tools would mean its hard to get it jacked up and have access to the drain bolts underneath the car.

Besides that my driving is improving, no longer worried or anxious about traffic or rolling backwards. Still trying to make sense of rev matching and and when to downshift but I will hopefully get there soon enough!

[knuckles61]

Also identified some potential causes for all the noise. The sway bars have been upgraded and have the polymer bushings, they looked very dry and the shocks might have some rubber in them from the protective housing (boot?) that has pretty much been destroyed. I might look into new shocks in the future but for now things will stay the same.

[JasonFriday13]

So I will start to empty out the radiator and refilling periodically it with a recommended coolant, after 3 or 4 cycles most of the gunk should be gone hopefully. I will look to see if I can get a manual and flush it out properly but I think my limited tools would mean its hard to get it jacked up and have access to the drain bolts underneath the car.

Don't bother wasting your money on fresh coolant every time you change it. Make the job quicker and just use water. Put the heater on hot. Warm it up to temp so that the radiator fans turn on and off, leave it over night to cool down, drop the old water out, put new water in, bleed it up. Do this a few times, using water for a short amount of time isn't going to hurt the cooling system. When you do the final flush, then you put the coolant mix in and bleed it up. I prefer a 50/50 mix for my cars (or close to it if I can).

Or if you want to spend a day or two at it, you can remove some of the pipes off the car and hose them out, this includes the radiator. Don't remove the heater pipes, they run above the fuel tank. You can put a hose on one fitting and catch the fluid out the other.

[knuckles61]

Don't bother wasting your money on fresh coolant every time you change it. Make the job quicker and just use water. Put the heater on hot. Warm it up to temp so that the radiator fans turn on and off, leave it over night to cool down, drop the old water out, put new water in, bleed it up. Do this a few times, using water for a short amount of time isn't going to hurt the cooling system. When you do the final flush, then you put the coolant mix in and bleed it up. I prefer a 50/50 mix for my cars (or close to it if I can).

Or if you want to spend a day or two at it, you can remove some of the pipes off the car and hose them out, this includes the radiator. Don't remove the heater pipes, they run above the fuel tank. You can put a hose on one fitting and catch the fluid out the other.

Think I will do the first suggestion, sounds like a much more efficient method than what I was planning. I think I will remove the reservoir tank to wash the rubbish out of that, there was a lot of stuff sitting at the bottom! Thanks for the advice, really appreciate it!

[knuckles61]

So quick coolant flush update

I dumped all the coolant out and I regretted it since the coolant was the perfect green colour, but shortly after things went brown. It stayed brown for a really long time and I just kept adding water until the water coming out was clear. Filled it and turned it on and started the bleed but I couldnt get the hose water levels up (parked car on a downhill) and then got scared the engine was going to get hot. So I turned it all off and I will dump the water again tomorrow then refill with coolant.

Might take me another day if things don't go smoothly tomorrow but still really glad I started the process.

[Benckj]

I tend to leave the rad bottom tap open and keep the engine running while having hose with clean water being fed into rear cap. This lets the water circulate through engine and core flushing sediment out tap. Usually takes a good 15-20 min with engine up to temp to get flushed clean.

[knuckles61]

I tend to leave the rad bottom tap open and keep the engine running while having hose with clean water being fed into rear cap. This lets the water circulate through engine and core flushing sediment out tap. Usually takes a good 15-20 min with engine up to temp to get flushed clean.

Thanks for the advice!

Yeah this might be the way to go today, does the engine not end up ruining hot though?

When I do fill the car back up with coolant should I have the car running? Or is that not safe since I imagine I hot water will bubble out.

[Swampy]

When I do fill the car back up with coolant should I have the car running? Or is that not safe since I imagine I hot water will bubble out.

This book I read said run 30% coolant "or straight water with an additive such as water wetter for maximum cooling" in the summer FYI, I would have the car cold, just because you have no coolant in there doesn't mean that what would usually happen if you removed the cap wouldnt happen.

[GDII]

Coolant isn't just for 'cooling'. It has anti freeze and anti boil properties plus the main one of being a corrosion inhibitor. MR2s are bad on coolant because of the many different types of metals in the system. But that's another topic.

[Swampy]

That's true. Running pure water would be bad.

[knuckles61]

I was only running it to flush out the other crap. While refilling do I have the car on? To be honest I'm worried of hot water bubbling up onto me!

I got my deionised water ready to go will be a fun afternoon!

[GDII]

Have you checked the BGB/service manual for how to do a coolant refill/bleed? This shows you exactly how to do it.