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IS300 SPOTRSCROSS 2001, 75k fsh

Mystery water loss

Hello All.

I like many others have exsperienced water loss with no obviose leakage. For the the last couple of years it wenr from an occaisional top up to having to fill the rad every 70-100 miles. I thought it may be a pressure problem and changed the rad cap. Then a water test for head gasket, Phew. The car ran perfectly as all ways and Over a long period I studied the engine etc waiting for something to rear it`s ugly head but nothing and no sign of a leak

BRAIN WAVE....... I dismemberd 2 high lighter pens and decanted them into a gallon of water and put it in the car and in a dark place went over the engine etc. with a cheapo ultra violet light and voile......A small sweaty leake in the radiator.

The rad has a lower tank and was leaking and the point where the core meets this lower tank. This lower tank has a raise lip of sevral millimeters and the water was sitting in what ammouted to a trough and then on I presume was just evaporating through the heat and wind so there was no easily visable sign.

I got a standard rad from fleabay for about £150.00, by way of a foot note, it had  two fixturs to accept some piping that was not required on my model of  car. I fitted them anyway after crimping them shut and soldering the ends and the good woman fitted it two days later. This was three weeks ago and the problem is solved.

I thought I would share my exsperience because thats the kinda guy I am.


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I think you will find the two pipes that you did not use was probably for a oil cooler for a auto box 

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What Tony said, thats correct, I have an auto and those pipes do indeed lead to the autobox. 

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