Coolant leak - can't work out why

  1. My model of MX-5 is: mk3.5, 2010, 1.8, 65k
  2. I’m based near: Hastings
  3. I’m looking for technical help or recommendations on: coolant leak

Hi. My mx5 overheated, and that was due to a lack of coolant. Having investigated, i have found a big leak when the engine gets warm - it comes out in a small stream, not just dripping.

From what i can tell, it is coming from the edge of a gasket, next to a bolt (which appears to be one holding the sump on). You can see the bolt in the picture (to the left and above of the oil filter in the picture). My fears are that the head gasket has gone, but from what i can tell there is no sign of coolant on the dipstick, in the oil filler cap, and the engine runs ok with no smoke out of the exhaust.
I can’t work out what part of the engine i am looking at - i can’t track down a schematic on the web.

Help would be much appreciated. Thanks

Hard to tell from that pic. Have you checked the 2 hoses to the thermostat and the thermostat itself for cracks? It’s under the intake and associated hoses etc passenger side. Easily removed for inspection although the stat is somewhat buried under there and more difficult to remove but doable, I’d start there.:+1:

Could the overflow tank have been overfilled?
Any excess would be expelled as the coolant warms up??

hi. thanks for the reply. I think (?) i have found the cause. A clip had come away from its hose, on a coolant hose (one of a pair of hoses) just above the oil filter. I can’t work out what component they are connected to. But i have refitted the clip and am also planning to get a 2nd clip on there - in case the 1st clip wants to work its way free again.


It didn’t come off on it’s own, someone’s done a job on there and not put it back.
Don’t waste your time putting extra clips on.

Fingers crossed you’ve sorted it