Hi,

This is a subject not many know about, but let me tell you , after 1 heater core, 2 radiators, 1 water pump and 1 cylinder head, my brother is wishing he new more about it.

The story started with the heater core letting go in a big way. A quick bypass on the road and he was mobile againg, bit not for long before the water pump let go. Boy what a saga, the water pump was renewed and happily back on the road when suddenly the radiator let go.

Now this is all getting a bit to much. A brand new radiator was fitted and would you believe it just 9 days later this new radiator let go with 15 pin prick holes in it.

If that wasn’t bad enough, the alloy cylinder head packed it in as well.

We’re talking serious dollars here and all because a new piece of electrical equipment wasn’t earthed properly.

You see if there is an earthing problem in your vehicle, electricity will somehow find a way out and it did it through the cooling system of my brothers Mazda Bravo.

This can be easily checked by placing the negative probe of a good multi meter on the negative terminal of the battery and placing the positive proble in the radiator neck submerged in the coolant (careful not to touch the metal radiator). The guage should register below 0.3 of a volt, my brothers was registering something like 4 volts.

He still has a problem, as it registers 0.51 of a volt which is still too high. A lot of questioning and I found out the radiator guy used a coolant you had to add water to, and you guessed it, he used just normal old tap water. This is one of the worst things you can do to a radiator, as normal tap water has too many chemicals in it and conducts electricity very easily, causing electrolysis.

Only use pre-mixed coolant or if you must use water, make sure it is DISTILLED and only DISTILLED.

So the next job for my brother is to drain the cooling system again and use the right stuff.

See you put there!

Tip:

If you're like the majority of 4x4 Drivers, you won't be able to change the diff oil until you get home, because you won't have spare oil and a sump pump to change it. If you suspect contaminated oil (a deep water crossing without extended diff breathers or perhaps you have leaking diff seals) then you can try and remove the water by draining the diff until only oil comes out the drain hole. Do not drain too much and leave your diff short of lubrication. Collect this oil and water emulsion as you should never dispose of oil into the environment. Save it till you get back home and dispose of it properly. Its not only diffs that can have water contamination, but also your gearbox, transfer case and engine oil. However, it is usually only when a 4x4 is stationary in deep water that these components are contaminated.