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still overheating :(


jackso11

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Daft question but is there an easy way to tell if my water pump has gone? Is it a case of removing one side of the top rad hose and seeing if there is any coolant coming through? I am using halfords coolant, I know some recommend the toyota red stuff but is there that much difference? Does the red do better on temprature?

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I have a FMIC, twid rad fans and wasn't going that fast, what is the agreed upper limit for coolant temp? Wonder how BPU SMIC people are fairing. It's the hottest day of the year tomorrow and I am off to London, don't think I will take the Supra.

 

perhaps the nice and shiny FMIC is reducing the efficiency of the RAD.

 

My CW SMIC seems to be coping just fine stuck in london traffic.

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A few points to make here:

1) Coolant boiling in the expansion tank and coolant boiling from an unscrewed rad cap are 2 different things. They may or may not have the same root cause. You would always expect the coolant to boil over in spectacular fashion when unscrewing a rad cap from a hot engine. That's normal. The coolant boiling in the expansion bottle is not so normal AFAIK: I can't remember if the cause of this is lack of coolant pressure, overfilling the coolant, or something else. If it's caused by lack of pressure, The-Plethora should try replacing the rad cap for a new one. The seals on the caps don't last indefinitely.

 

2) This is a bit slack of me as I haven't recapped on the rest of your thread jackso11, but your symptoms in your latest posts sound a lot like a tired inefficient radiator. Putting the interior blowers on to hot gives the cooling system a supplementary radiator (i.e. the heater matrix) which it can use to lose heat from the engine. I used to own a car which had these sorts of symptoms: the radiator was well past it (it barely had any fins left), and putting the heater on to hot made a visible difference in keeping the coolant temperature down.

 

3) The-Plethora: using either Toyota red or a generic (.e.g Halfords) coolant shouldn't make any difference. The generic one will be just as good as the Toyota stuff as long as the generic is mixed to the correct concentration with (preferably distilled) water, and isn't ancient. The generic one must be ethylene glycol -based, but almost all of them are.

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Cheers for the pointers, as some as you know I am still learning some of this stuff ;)

 

I took a few pics, maybe they might point to something?

 

This is my current rad camp, the car had a TRD one on when I bought it which fell to bits, this was in the boot and I presume a stock one? I have been running it since around November without issue.

 

image

 

Bottom of the rad cap

 

image

 

Here is my expansion tank

image

Maybe I am missreading this? the expansion tank piping is loosely tied along its path and with the downpipe into the expansion bottle it's a bit tricky to take it out all the way. Maybe it was just trapped air pushing out through the expansion tank making it appear to bubble?. Although after being parked for several mins I would have thought it would have stopped

With the rad cap I thought it was essentially just a seal, does it relieve preassure when it reaches a certain preassure?

 

The cat is oblivious to my problems :(

 

image

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As imi said, the expansion bottle doesn't look stock. It's not even in the same location as the stock one. However, let's assume the relocation isn't causing the problems.

 

The rad cap acts as a pressure safety valve. It holds pressure up to a certain point, and if it exceeds it it's designed to pop off, like the rubber bung on a pressure cooker. Personally, I wouldn't trust a cap that I'd found rattling around in the boot. Search on here about causes of coolant boiling in the expansion tank, and if it's a lack of pressure in the system then change the rad cap for a brand new standard one: they're not expensive.

 

When you park up and turn the engine off, the coolant will get hotter over the next few minutes as it no longer has the cooling effect of airflow whilst moving.

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Its been to someone who knows what they are doing. Its been to garages who don't know what they are doing, then with Supraloopy on here, nobody can find anything wrong with it.

 

Bleeding an airlock, first thing people say is take it for a drive to get the temp up, then open the rad cap.....if its first class stupidity then every post on here about how to get rid of an airlock needs to be edited.

 

Personally I always bleed from cold and just leave it running to get the temp up, but as that doesn't seem to have worked I thought I would follow peoples advise and get it up to temp before bleeding.

 

I would offer that I either fix it or don't charge you. It will be something fairly basic, I am sure. All this "bleeding talk" is nonsense :), it will self bleed if just left iling with the cap off, it has no need of anything special.

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Don't mean to thread hijack but started mine up today and went for a quick drive round the block. I would say the water pump is working as the rad gets hot along with the pipework. The rad was fairly toasty but the fans did not come on, on saturday I did remove part of the FMIC pipework to fix my BOV problem. Is it possible I could have knocked a thermostat? If so is it the wire going into the bottom of the radiator?

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How does the stock SMIC fit into the cooling system? I know its there, but it is just another radiator that the coolant flows round? or is it an air cooler?

 

I am assuming that the question is due to my comment about fmic, I simply speculated that a huge fmic right in front of the rad would effect it's efficiency. Must've some logic in why Toyota decided not to have an IC there.

 

Imi

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It was partly do do with your comment imi :) I know an FMIC restricts airflow and can cause over heating, I just thought about the SMIC because I had no idea how it works :)

 

An SMIC is just an FMIC on the side, side mount intercooler. No more magic than that :)

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Chris has made me think of a new idea for this problem. It only happens when the weather is hot, but also I only have the aircon on when it is hot. When I was looking at it at the weekend I don't think the aircon fan in front of the radiators is working, which I have read comes on when the coolant reaches 98 Deg or if the aircon rad gets too hot.

 

I thought you could remove these fans with no ill effect, however, maybe if I put a new working fan in place (which I have in the garage but haven't installed yet) this will fix the overheating issue.

 

I am not sure if the problem is only when the aircon is on, but there is a strong possibility that it might be! Weekend job.

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Thanks chris :) I didn't think to check the aircon fan but it makes sense that it started in the hot weather as thats when I started using aircon.

 

I will find out when I get the front end back on if its fixed or not :) Just ordered a load of new bolts as I thought I would change the rusty headed ones while they are off......£50's worth from Mr.T :shock:

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Think I might have fixed this. The aircon fan in front of the aircon rad wasn't working, and the small fan in the rad cowl wasn't coming on. Both working now, just need to get my front end back together :)

 

Well done, I would say you are a very big step closer to fixing this.

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