Coolant Loss

[Flibby]

Hi all,

Having been working from home since March, and the weather being so poor, my 2's usage has much reduced 

I got out last weekend and noticed that the coolant level was a little low. I topped up but after each use the level dips down again. The level doesn't appear to go down when the car is sat.

I hoped that it was a similar issue to one that I had last year. I checked the level one day which was low, i topped up and then somehow by magic the level had gone to to way over the 'max' level the next time i checked it. Whether this was a small air lock or something I don't know...

I'm going to have the bumper off at the next dry opportunity anyway to replace some fog light holders, so my plan is to check the following, with the engine running:

1. Radiator bottom;
2. Pipes running laterally between block and rad;
3. Rad plastic pipes;
4. Water pump & housing;
5. White smoke from engine (head gasket leak? not heard of this being much of an issue with MR2s...)

Am i missing anything? My fingers are crossed for a leaky rad but any significant leak there would surely drain without the engine running? Only 75k miles so she's still a comparative baby 

Cheers!

[Carolyn]

The cooling system pressurises when it gets warm.  So a small leak may only open up when the car is used.

At the age of your car, the radiator has to be the most likely culprit.

Head gasket failure is very unlikely. 

The system shooting up is a symptom of air getting in - again an old rad is a likely culprit. 

I'm not aware of any plastic pipes in the cooling system -all reinforced rubber or ally.

If it's the water pump there'll be coolant droplets on the edge of the sump.  The housing is part of the timing cover and is only ever a problem if the cover has been off.

[Topdownman]

Lots of us have taken the bumper off only to find the bottom corner of the rad rotted away.

Hopefully thats all it is as not too expensive for a replacement.

[Ardent]

30 35 quid ebay.

[Joesson]

At 75k, from personal experience and what I've read on here I must agree with all of the above responses concerning the radiator, bottom left, likely visible by removing the frunk cover.
If your coolant is "new" and long life much could be saved by clamping the hoses next to the radiator. This could also help with refilling and bleeding the system. You may want to consider replacing the two OE hose clips with Jubilee type.

[normanh]

Again - the rad mine rotted out over a number of years held out with a sealant in the coolant for years never leaked that much about 2 litres over years. So hard to see unless you take the rad out or remove the bumper. A new one is the only answer, when you replace change those silly spring hose clips to proper stainless clips, I had one fail behind the rad on the steel pipes so dont forget those as well.

Norman

[Flibby]

Thank you very much everyone. You have reassured me thay it's likely the rad. Hopefully the weather breaks this weekend so I can have a peek and I will report back 

[Flibby]

I'm reporting back...


I made two discoveries. Firstly, a lump hammer from some previous work which was no doubt offering me some increased weight into corners 

...And a pool just behind the radiator. The rad itself looked in OK shape and I couldn't see any spurting, but would you agree that this confirms the likely diagnosis that you all made that the rad is shot, in the same place identified?

[Carolyn]

Yep.  Time for a new radiator.  Free lump hammer with car eh?  What a bargain!

[Flibby]

Yep.  Time for a new radiator.  Free lump hammer with car eh?  What a bargain!

More embarrassingly I'm fairly sure it was mine that I'd forgotten in a senior moment

[Carolyn]

Yep.  Time for a new radiator.  Free lump hammer with car eh?  What a bargain!

More embarrassingly I'm fairly sure it was mine that I'd forgotten in a senior moment

I have those all the time. 

[Chilli Girl]

Well at least now you know the problem.  Good find Nick and the hammer!

[Joesson]

Yep.  Time for a new radiator.  Free lump hammer with car eh?  What a bargain!

More embarrassingly I'm fairly sure it was mine that I'd forgotten in a senior moment

I'm intrigued, I had such an implement, (I believe it's a rawhide mallet), in my machine shop days and used it for "tapping" work pieces into position. I just wonder what needed that much "persuasion" in that area of a 2.

[Flibby]

It's half rawhide and half copper. The rawhide has somewhat deteriorated now 

It was probably used to 'tap' out the old steering knuckle just over a year ago. Not exactly a precision tool as you say 

[ookmen]

Yes I had same problem with my coolant level , it was right at the bottom under the minimum level I did 1litter Coolant it is ok at the moment but I keep my eye on it 😰

[Joesson]

Yes I had same problem with my coolant level , it was right at the bottom under the minimum level I did 1litter Coolant it is ok at the moment but I keep my eye on it 😰

I really don't believe that situation will improve without intervention.

[normanh]

You can try a rad sealant it can slow it down, prior to changing my rad I used about 4 litres of coolant to 1.5 litres of oil in in 10 years.

Norman

[Carolyn]

You can try a rad sealant it can slow it down, prior to changing my rad I used about 4 litres of coolant to 1.5 litres of oil in in 10 years.

Norman

Sorry to contradict but -that's a rally bad idea in our cars. It can cause problems with the heater matrix.

[Ardent]

Yes I had same problem with my coolant level , it was right at the bottom under the minimum level I did 1litter Coolant it is ok at the moment but I keep my eye on it 😰

Just a heads up. The coolant level can seem to have a mind of its own.
That said,if you suspect you are losing some. Look towards bottom left of rad.

[normanh]

Never had a problem with the heater in 10 years, I know the problem and it mainly arises when the heater matrix leaks the sealant effectively blocks it then no heater.

Norman

[Gregmorse]

Just be sure to burp and bleed the coolant system the proper way. Expect it to take up to several hours...