45 replies to this topic

[unburntfuelinthemorning]

Oh ok; I missed out on O levels by a few years, got some of them GCSE things.

 

People often ask about spraying aluminium radiators black.

[Pops_Guild]

 

 

As noted in one of my earlier replies I did notice the aux fan didn't come on/wasn't on...that could be 100% the reason for the overheat but it might not have been helped by the old rad. It might be a symptom of something else?

 

I've owned enough Mini's to know overheating is a thing they do and that is why I spent effort making sure all the waterways were cleaned up or new in the restoration, everything except the rad that is, which I completely cleaned...or so I thought

 

If it was overheating in slow moving traffic you could blame the fan but the engine driven fan is hurling loads of air through the radiator at 65 mph. 

 

Is the thermostat opening fully?  Is the radiator cap the correct rating and is it working properly?

 

 

The AA man said the same about the aux elec fan, only really useful in slow traffic.

 

The thermostat (standard 88deg) and cap are both new. I didn't test them before fitting, so there may be a fault in one of those. When I lifted the bonnet it was spitting hot rusty water out of under the cap...

 

Not sure how you test a cap?

[unburntfuelinthemorning]

Good question.  I'm not sure. 

 

Is the expansion tank fitted?

[nicklouse]

The thermostat (standard 88deg) and cap are both new. I didn't test them before fitting, so there may be a fault in one of those. When I lifted the bonnet it was spitting hot rusty water out of under the cap...
 
Not sure how you test a cap?

you say it is overheating but don't say how you know (or think it is) you now mention the cap! why?

 

you say it is new. you do know there are different pressure caps? did you also know there are different sized caps (long and short) for different length necks.

 

have you done a compression check?

 

have you put any cleaner through the engine? rust in the block can cause big issues.

 

run the basic tests before replacing things that may not be the issue,

[hunterg30]

And if you use an alloy rad you need to use the right antifreeze

[cal844]

I installed a Fletcher 2 core rad in my Clubman Estate, the cap is a 16psi one, its smaller than standard but it works.

The car seems to prefer slower speeds, anything above 60 and the needle comes up to 3/4 guage but it hasn't boiled over or pushed coolant out the overflow so it's not the radiator.

I use Comma super cool antifreeze (pink stuff) in my Estate

Edited by cal844, 15 May 2019 - 03:30 PM.

[Pops_Guild]

Good question.  I'm not sure. 

 

Is the expansion tank fitted?

 yes the expansion tank is fitted, presumed working

[Pops_Guild]

 

The thermostat (standard 88deg) and cap are both new. I didn't test them before fitting, so there may be a fault in one of those. When I lifted the bonnet it was spitting hot rusty water out of under the cap...
 
Not sure how you test a cap?

you say it is overheating but don't say how you know (or think it is) you now mention the cap! why?

 

you say it is new. you do know there are different pressure caps? did you also know there are different sized caps (long and short) for different length necks.

 

have you done a compression check?

 

have you put any cleaner through the engine? rust in the block can cause big issues.

 

run the basic tests before replacing things that may not be the issue,

 

 

 

Thanks Nick, lots of questions :)

 

you say it is overheating but don't say how you know (or think it is) you now mention the cap! why?

 

>>> Well, the temp gauge went top of the red after being solidly in the middle for over an hour of driving. Pulled over and the bonnet was steaming, opened it and rusting water was spitting from underside of the cap. Also stream of water under the car. That's overheating my book :). I mentioned cap because of the spitting, someone else asked about it earlier and the AA man looked at it as a potential culprit.

 

you say it is new. you do know there are different pressure caps? did you also know there are different sized caps (long and short) for different length necks.

 

>>> Yes its new and yes I am aware. It's a new 92-96 SPI with sensor cap. Would seem to be correct for my SPI Cooper.

 

have you done a compression check?

 

>>> No, not yet, aside from this overheat everything seemed to be ok so didn't see the need. Would poor compression on any cylinder cause an overheat for a mini when driven over 65mph, sounds like it?  I can do one though...

 

have you put any cleaner through the engine? rust in the block can cause big issues.

 

>>> No, not yet. Again until the overheating it all seems to be good. Sounds like a good thing to do though. Any recommendations on which would do the job?

 

run the basic tests before replacing things that may not be the issue,

 

>>> Too late for that :). It's been through a 3 1/2 year rebuild, but not much touched with the engine block itself other than servicing. Have replaced only obviously broken stuff or things that I knew were suspect. ACR2 checks are all good, all good/expected numbers. I avoided replacing the rad for that very reason, the original cap was dead.

[imack]

Is the engine driven fan fitted the right way around?

[Pops_Guild]

Is the engine driven fan fitted the right way around?

 Yes. Also checked by the AA man :)

[unburntfuelinthemorning]

have you done a compression check?

 

>>> No, not yet, aside from this overheat everything seemed to be ok so didn't see the need. Would poor compression on any cylinder cause an overheat for a mini when driven over 65mph, sounds like it?  I can do one though...

 

I think he was thinking that you should check for possible head gasket issues.

[riktanius]

I know it isn't popular, but has anyone used one of those kits from Aliexpress? They have some nice looking rads and pipes. They aren't original, but I don't care about that at all.

[guywilko]

Change the cap first

[gazza82]

I know it isn't popular, but has anyone used one of those kits from Aliexpress? They have some nice looking rads and pipes. They aren't original, but I don't care about that at all.

The Chinese/Taiwanese ones?

[expat_cat]

Is the picture on your profile of your car?

I can't even see the front grill due to all those big spots!

 

Given that it overheats at speed, just for a laugh take off a couple of the lights and give it a run.

 

Might not be the actual base problem, but won't help