Next thing I know, \"boomph PSSSHCHHCHHHHH\" and there's steam coming up from under the bonnet. Oops.
Turns out that the thermofan wasn't turning on, so I guess that the cooling system pressure climbed too high when the enigne got hot, eventually finding a weak spot in the cooling system - which was the driver's side of the top radiator hose.So while I was waiting for things to cool down and see what I could do about the hole, a mechanic happened to pull over and see if I needed help. I was pretty well sorted, but he had something I didn't have - electrical tape! I opted to soldier on instead of get towed back home. So, eventually when the coolant stopped hissing out, I had a look at the source of the leak, which was a hole about 2mm in size. After removing the cap (after the system had depressurised) about 2L was missing from the cooling system - that wasn't really that much of a problem, as the cooling system of the car with the PWR radiator made for a greatly increased cooling system capacity.
I checked through the car but was unable to find anything that we could bind up the hole in the top radiator hose with, so we used the electrical tape he had. The top hose was then bound up and put back into service on the car. I also jumpered the diagnostic connector to make the thermofan run full time until I get the thermofan controller sorted out. It's held up for a few days now.
So, yesterday I went a parts-hunting, figuring that I should replace both of the hoses. First stop Repco, as I knew I'd be disappointed and end up going elsewhere. Top radiator hose? $101. Bottom hose? $60ish. HAHAHA yeah, as if. $160+ for TWO hoses?? This is why they're fondly known as Ripco.
Stop #2 - Supercheap. Unfortunately, Grommet (the supplier of Supercheap's cooling hoses) do not specifically stock a hose for MX-5s, so I was out of luck there. And then Mazda - $55 for the top hose, $45 for the bottom hose. I thought about it for a while and could not fathom how the hoses could be so expensive - so I thought around the problem a bit. Supercheap had a whole bin full of coolant hoses, and at least one of them is surely bound to fit my application. Using the digital verniers, I measured the radiator outlet and thermostat housing outlet for the inner diameter of hose required. With that info, I went to supercheap to look for hoses of the appropriate length. I came up with two winners - a Toyota Corolla hose (part number GR38) and a Holden Commodore hose (GR63). In hindsigbht, two GR38s would have fit the bill nicely. Here are some comparison pics:
The inner diameters are only 1-2mm smaller - if it gets a bit tight then it's nothing a bit of soap or warming up of the hose ends can't fix. And the cost for these hoses? $10.60ea. And all I have to do to make the hoses fit is shorten them with a knife!
So with a bit of shopping around, I've saved myself $70 if I had gone to Mazda or $140 if I'd gone to Repco!
Some OEM parts are such a ripoff. And it's not everyday that the aftermarket equivalents are double the price. it pays to shop around and do a little bit of improvising.
We should have stuff like this in the tech archive. Are you adding it to your site.?
