coolant leak from intake - NA

[shirtz]

hi guys, let me know if this is the wrong forum for this.

so I just bought my first na. hadn't been dríven for a while and when I drove it and gave it some stick it popped radiator fluid onto the inside of the bonnet and below the intake. wasn't much, and the car was cheap so I bought it anyway lol.

so now on inspection when it heats up its still happening (obviously!). super hard to see where its coming from but somewhere above the oil filter.

anyone have any ideas? perhaps the manifold gasket? what water pipes head in under there?

any help would be great.

[smy0003]

There's two 'Devil' water hoses (on the NA8 at least). One rund from the back of the head to the oil filter housing and the other from the oil filter housing to the throttle body.
See here for a pic:
https://s13.postimg.cc/ahspnf3yf/IMG_3761.jpg

Googling "devils hose miata" will give you step by step instructions, part numbers etc. It's a bit of a PITA but not expensive.

[kalt]

Clear photos would help, otherwise we'd be taking potshots into the dark.

[shirtz]

thanks for the replies. its a 1.6, do they also have the "devil hose"?

as for pictures, sorry, its EXTREMELY hard to see (I cant pinpoint it), let alone photograph. as I said, if your looking from at the passenger side of the car, the leak is coming from above the oil filter under the IM. cant see where. has also popped some coolant under the hood in the same spot. can get some photos tonight of the general area if it helps. only happens when the car is up to temp.

[manga_blue]

The first job you should do when you buy an NA is replace every single coolant hose. This spares you from random breakdowns stretching out over the next year or two.

Buy about 1.5-2.0 meters of 8mm Gates Premium Heater Hose and good quality new clamps from Repco for all the little hoses around the back of the head, oil filter, throttle body and front of the motor - these are the ones that fail most often and yours is probably the most common failure of them all: from the back of the head to the oil filter mount. Check for an oil leak at the same time at the back of the cam cover on the intake side around the CAS sensor. It's an oil dripping from there onto that hose that causes it to fail so often. The leak is fixed by replacing an $1.00 standard o-ring to the CAS. Google MX5 CAS o-ring on miata.net for more.

Then buy OEM or Gates hoses for the top and bottom radiator and heater core connections.

[noobee]

put your location in your profile and someone local may even help.many areas have the occasional "dodgy day" which usually aren't
dodgy at all.(mostly,lol)
Mick

[smy0003]

Take the drivers side wheel off and look up through the wheel well to see the oil filter clearly.

Sent from my LG-H815

[shirtz]

thanks for the great replies guys. looking forward to becoming a contributing member instead of a knowledge leech

I assume to get to the pipe that's the likely culprit ill need to take the intake off?

looks like ill be buying lots of hose!

im in canberra by the way if anyone is around and local, be good to meet.

[noobee]

I can vaguely remember doing mine when I had an na6.its a little different to na8.didnt need to take the intake off,but cant remember much else.
Mick

[93_Clubman]

Welcome & congrats on the buying an NA6.
https://www.miata.net/garage/CoolingSystemProblems.html
As the car's been sitting for a while & it's 24-28yo, for reliability it would be worth while baseline servicing it, ie full inspection & service.

[ianoz]

Mx5mania do kits with all the coolant hoses, preformed so they fit easier. Don't forget the Cursed Water Plug at the back of the engine too. Nice picture in this thread http://mx5cartalk.com/forum/viewtopic.php?f=29&t=74158

You can do them with the engine and manifolds in place - and it's a great opportunity to develop new swearing skills....

[shirtz]

thank you all so much. looks like hose repacement is happening before i go for rego. time to get dirty and swear

[StanTheMan]

above the oil filter is probably this location

image002.jpg