SP Overheating

[SPy vs. SPy]

I performed a routine check of my wine glass, so I returned to the kitchen..... It was then when I noticed my coolant reservoir was "mighty dry"....

Edited for legitimacy

I've had mine to Mazda about ten times chasing a boiling sound, the official word is some SP's do it some don't.

I've seen the temp gauge go crazy on spirited uphill climbs on stinking hot days with the A/C on but not at 110km/h along the freeway.

As Benny says the radiator can get clogged. A reputable radiator shop should have a heat gun to measure the temp across the radiator, it will need to be pulled out to fix. If mine does it again I'll try and get a BIGGER radiator.

Darbs, from what I have observed the overflow bottle can go from full to empty to half full to a quarter all in a few hours of driving.

[MX5-SP]

I performed a routine check of my wine glass, so I returned to the kitchen..... It was then when I noticed my coolant reservoir was "mighty dry"....

Edited for legitimacy

I've had mine to Mazda about ten times chasing a boiling sound, the official word is some SP's do it some don't.

I've seen the temp gauge go crazy on spirited uphill climbs on stinking hot days with the A/C on but not at 110km/h along the freeway.

As Benny says the radiator can get clogged. A reputable radiator shop should have a heat gun to measure the temp across the radiator, it will need to be pulled out to fix. If mine does it again I'll try and get a BIGGER radiator.

Darbs, from what I have observed the overflow bottle can go from full to empty to half full to a quarter all in a few hours of driving.

I think we have all seen the reservoir level vary temporarily due to expansion/contraction of the coolant. However, as it is supposed to be a sealed system the actual loss of fluid can only indicate three possibilities:
1) the coolant has been 'pushed' out of the overflow due to excessive expansion, such as air in the system; or,
2) a hidden leak (such as a blown headgasket); or,
3) I've been tapping into it ...instead of the cask in the fridge

There's no obvious signs of external leaks, and no water (coolant) in the oil. So, in the absence of all other proof, it appears number (3) is the likely cause.

I'll keep an eye on it from here on, and treat myself to a new cask of Moselle on Friday.

[AL]

I've been reliably informed that the bubbling that you here is steam escaping from around the head and trying to vent to the reservoir bottle. Some cool down idling or a turbo timer will help

[Garry]

Check you turbo coolant hoses. My car used to use a small amount of coolant after Mazda replaced my turbo and occassionally I could smell a waft of burning coolant. Every time I took it back to Mazda to get something fixed or a service I got them to check out the cooling system. Every time they pressure tested it and it came up fine. It took me almost 2 years but I eventually found the problem. The coolant was leaking from where the rubber hoses fit onto the fittings at the turbo. They hadn't been clamped on properly. I actually saw green coolant there once but the pipes were also stained brown from where the coolant had been dribbling down them.

If your turbo coolant pipes have more than 50k km on them there's a good chance that they are hard and brittle and ready to crack so you should handle them carefully. The Pirteck hose Mazda used on my car isn't up to the application. My second set of hoses that are only 2yrs old with 50k km on them were even hard and brittle on the end that fitted onto the water pump.