Calling all owners of black MX-5s

[NiceCupOfTea]

I don't really trust the cooling system on my car at the moment - it's had some new pipes and a new water pump but I can always smell coolant from it. It's not losing anything that I can see and got my garage to check it at the last service and they couldn't see anything, but I'm sure I;ve heard something boiling under the bonnet a few times recently on very very hot days. I suppose it could be the a/c making a funny noise, but...

Anyway, the bonnet gets very very hot on a hot day like today - just lifting it up I can't hold it for more than a few seconds. Is this the same for all black '5 owners?

[JJCW]

Racialist

[NiceCupOfTea]

JJCW said:

Racialist

Whoops - just re-read the title! Mods, can you change the title to "Calling all owners of black MX-5s!" before I start getting hate mail!

[Quick silver]

All black vehicles get very hot in direct sunlight, in fact anything black at all......I imagine it's all in your head, the smell is more than likely residue burning off from having the new pump/pipes fitted & the's a good chance that new pipes themselves will smell for a while also.

I relaced a cylinder head on one of my 4X4's a few years ago & remember panicking over every little smell & noise for some time after..........also keeping a firm eye on the temp gauge - I'm suprised that I didn't end up looking like Marty Feldman

[zac510]

I notice that the mx5 bonnet is quite thin and has no underbonnet insulation so I am not surprised it gets very hot very easily.

[NiceCupOfTea]

Thanks guys. QS - I know what you mean about that smell/noise paranoia The water pump was about 6 months ago now though so there shouldn't be any residue...

I am due an MOT soon so I'll ask them to pressure test the system and maybe I'll change the rad (hey it's nearly a couple of months since I last did one )

[Quick silver]

To add, the bonnet is aluminium & an excellent conductor of heat.

[vrooom]

My car is black, my bonnet does get little warm. but not too hot to touch.

[OnlyMX5ives]

If you're not actually overheating, nor loosing coolant (you are checking the rad NOT the exp tank ?)

Then I wouldn't worry.

However usually if you can smell coolant (when yu're in the car) then the heater matrix is the usual suspect.

[NiceCupOfTea]

No, it doesn't overheat, and I do check the level in the rad, but I can definitely hear sizzling under the bonnet and smell coolant.

No damp carpets either. It's been suggested that it might be the radiator so I might replace that at some stage...

[zac510]

I wouldn't just go replacing stuff and hoping - that could get expensive!

There must be a leak somewhere and coolant being green, it will be visible.

Otherwise check in the overflow bottle for boiling, the rad cap might be broken.

[NiceCupOfTea]

Had a new genuine Mazda radiator cap a year or so back...

[vrooom]

Hmm check your radatoir's plastic for cracks, even small hairline crack can cause that.