16 replies to this topic

[TheHunterHofman]

Hi all,

 

I'm new here and currently working on my 2000 Mini Cooper S that has been sitting for years.

 

Three things I'm a bit worried about are the following:

1. this is how my engine looked like with the thermostat and thermostat housing removed, I have flushed the system completely with a garden hose and the water coming out now is 95% clear water. Would I still need to address this further? Image: https://imgur.com/QmlEUmL
2. this is what came out of my radiator (after flushing the radiator and engine block with a garden hose), a bit of oil looks to be in there, would that be a sign of blown head gasket? Note that no oil (or oil like substance) was found when flushing the engine block. Image: https://imgur.com/DNUk9YM
3. this is how my coolant reservoir looked like, it was completely empty (I vaguely remember it boiling(?) the coolant years ago before putting it away). I'm worried about the brownish debris on the bottom of the reservoir. Would that indicate something? Image: https://imgur.com/NfBW8j4

Many thanks for your thoughts in advance.

 

Regards,

 

 

 

[nicklouse]

I see nothing there to be an issue other than you remember it boiling.

 

first thing to do is after looking at the oil is pull the plugs and do a compression test.

 

if ok then add coolant and run up to temp. Have a infra red temp gun to check actual temps.

 

oh I would fit a new thermostat.

[TheHunterHofman]

I see nothing there to be an issue other than you remember it boiling.

 

first thing to do is after looking at the oil is pull the plugs and do a compression test.

 

if ok then add coolant and run up to temp. Have a infra red temp gun to check actual temps.

 

oh I would fit a new thermostat.

 

Thanks mate, I have checked the oil and it was still squeaky clean (it was serviced shortly before it was put away). I have ordered a new thermostat (although the old one still worked after boiling it in water). Will make sure to get a compression test kit. Thanks again.

[Quinlan minor]

Check the Header Tank

 

https://www.minispar...px|Back to shop

They are a frequent cause of boiling issues.

[Spider]

Hi and welcome to the forum, glad you've been able to find your way here.

 

There's nothing much from your photos that pokes me in the eye, the cooling jacket actually appears fairly rust and corrosion free, but looking at the bottom of the Header Tank, it does appear that the coolant wasn't as clean as it could have been and / or there's been some separation of it.

All the same, given the time it's been standing I'd suggest giving the cooling system a decent flush with one of the commercial quality products available (not those from the auto parts store). I was using CLR for many years, with good success, but recently I've been using Liquid Intelligence, which I've found super. Just keep in mind, with your model, it has an Aluminum Radiator, so be sure to select a product that's comparable with that.

The other items I'd suggest checking or just replacing out of hand is all the small vacuum hoses. I've not worked on these late Minis, but many problems with them appear related to these hoses perishing and cracking. Vacuum leaks can also be a source of overheating.

[TheHunterHofman]

Thanks for the replies everyone. So what I did now, was flush the cooling system with a garden hose, lots of old and dirty fluid came out. I flushed it until the fluid became clear again. I then reassembled everything, along with a new thermostat, a new coolant pump (the evo one, with the composite impeller), a new auxiliary belt, new gaskets for the thermostat housing and coolant pump, a new temperature sensor and a new valve cover gasket (but that's of no importance in this issue of course).

 

So I then let the car run, with the coolant reservoir cap removed, and filled it up with water, until it was full. I squeezed the large coolant hose to let the water pump through more easily. I actually made a quick edit of what happens now: https://youtu.be/fFromOqF7Y8

 

So in chronological order: I started the car after installing the above, filled it up, let it warm up, noticed the water boiling hence why I put the cap back on, noticed the water becoming brownish/cloudy, noticed smoke coming from the radiator, noticed the hoses became very hot (to the point touching them was impossible) and finally noticed that the water was still boiling in the reservoir (with the cap on). After turning the car of I could still hear the water boiling, and smoke coming out of the reservoir. 

Note that during all this, I turned the heater all the way up and the temperature of the coolant never rose more than perfectly in the middle.

 

Would anyone have an idea of what's wrong here? Apologies if I come across as an amateur. Today I will be receiving my compression test kit, so I'll be checking compression this weekend.

 

In terms of visibility, would it be wise to start a new thread?

 

Thanks a lot everyone, really enjoying my time on here so far.

[cal844]

You need to get the coolant 'sniff' tested for exhaust gasses. I'd say that it does sound like your head gasket has probably failed between a bore and coolant passage

[Bobs2293]

I wouldn’t jump into a head gasket. Looks like a problem with your radiator possibly blocked or ineffective. 

 

Do a compression test and maybe replace the radiator. Why is it leaking at the bottom as shown in your video? Also do a sniff test. 
 

The hoses will get very hot to touch and the coolant will become brownish. Don’t get bogged down on these two issues. 
 

Is the thermostats 100% opening?
 

Any white substances in your oil or oil cap?

 

[TheHunterHofman]

Thanks for the replies both. When spraying water with the garden hose through the large coolant hose, the one directly going into the radiator, the water only came out of the opening of the radiator, not through the middle of the radiator. The thermostat is new and opening (tested it with boiling water). No white substance in my oil (squeaky clean actually), or in my oil cap.

 

I'm not sure where to get such a sniff test here, I will look into it. I will first be doing the compression test this weekend though.

 

Thanks again.

[Bobs2293]

https://www.amazon.c...0B9YYN4BRS6YG02

[sonscar]

Looks OK to me not very scientific testing 90 degree hoses with a finger and declaring them hot.Does the cap seal?The radiator looks wet,is it leaking?the smoke is water evaporating off.The water never looked like it was boiling to me.If the head gasket has gone into a waterway the 150 psi into the water jacket is a joy to behold.Get an IR thermometer,make sure there are no airlocks,and measure it properly.Just the opinion of an elderly bodger,Steve..

Edited by sonscar, 10 June 2022 - 02:31 PM.

[cal844]

https://www.amazon.c...0B9YYN4BRS6YG02

That's the type I had in mind

[TheHunterHofman]

Thanks again everyone. The cap seals, I don't notice anything escaping from the cap (it being water or air). I'm don't think the radiator is leaking, however that smoke was there even after 10 minutes or so. Seems to me there might be a leak in the radiator then. I'll update once I have done the compression test. Thanks for the replies.

[Quinlan minor]

Thanks again everyone. The cap seals, I don't notice anything escaping from the cap (it being water or air). I'm don't think the radiator is leaking, however that smoke was there even after 10 minutes or so. Seems to me there might be a leak in the radiator then. I'll update once I have done the compression test. Thanks for the replies.

If there is a leak in the radiator, the "smoke", if it doesn't smell of burning, is probably steam.

The coolant will boil, at normal engine temperatures, if not subjected to the pressure of a sealed system.

There are radiator "sealants" available, though I wouldn't recommend them.

Take the radiator to a specialist, for check and repair, or replace it.

[Lplus]

If the thermostat seems to be working under test and the temperature guage reads cold when the engine is cold and normal when the engine is hot I'd say the temperature is correct( at probably 89C?).  This should not boil with the cap off though the pipes will be very hot.  Continuous bubbles with the engine running but the temperature normal suggest a leaking head gasket to me.  The rad leak is not relevant though of course should be fixed.