Water Leak, lots of steam, then overheating.

First off, hello all, I’m a newbie here. I’ve had a Eunos which ended in a ditch, and just bought a J-plate MK1 MX-5. Driving out in the middle of nowhere today, I looked in the rear view mirror and saw loads of smoke. I stopped, got out, found it was actually steam and there was lots from under the bonnet. So I popped the lid and it lost most of it’s coolant. The bulkhead on the passenger side (as you look from the front)was wet and the steam was coming from something getting on the exhaust. I expect it’s a split hose, but it was getting dark and I couldn’t see properly so I’m not sure. Got the car towed home by the AA.

 What I want to know is what for/where I should be looking tomorrow morning when it’s light? At first guess a split heater hose comes to mind, but  I haven’t got a workshop manual yet and it’s cold and dark, so any help to speed up my job over the next couple of days would be appreciated!

 Thanks all, happy new year!

 Mike P

G’day mate, Welcome to the Forum 

Pipes to the left of the washer bottle. Be care full taking them off, the copper pipes are very thin and bend easily, best way is to cut them through the middle and then slit along the length. Replace both pipes of course

 

What a top man. Spot on, thanks a lot for your help. It’s the left hand pipe on the pic that’s split behind the engine. Both pipes now off, waiting delivery of a new pair tomorrow!

Happy new year! Thanks again

Mike P

Hi, It might be a good idea to check that you don’t have an oil leak from the CAS ‘o’ ring. This tends to be the cause of the failed heater pipe, the oil drips on the pipe and attacks it.

Thanks for that. There’s no oil leaks that I can see, and the car has used no oil in the last 2000 miles since I’ve had it. The split pipe appears to have no oil stains on it, just a 2" long split on the underside of it.

Thanks for all the replies

Mike P

To check for an oil leak, put your hand under the CAS - it’s on the passenger side of the head, underneath the coil pack.

 http://www.miata.net/garage/cas_oring.html

 HTH

 

Edit: nice double-post [:S]
Edit: Not a problem…too easy mate

If the car is a 1.6, which from the rego letter it is [J plate, the 1.8 was introduced in July 1993 on a K plate] then the CAS is on the drivers side [inlet manifold side] This means that leaks do not contribute to rotting heater pipes, but are just a PITA

Dont forget a good dose of anti freeze [I]make sure it strong enough to go down to say -20 and make sure you bleed the cooling system to get rid of all the air in the system[Y]

Alan

Yep, it’s a J-plate. It’s not the blue one in the pics - I forgot to change the pics when I crashed that one :slight_smile: I now have a red J plate 1992 UK car. It’s a 1.6 and it’s not leaking any oil from anywhere :slight_smile:

Cheers

Mike P