Is it possible to determine the state of the engine coolant for rust just by sampling the stuff in the expansion tank? I recall on my V12 E-type that the stuff in the expansion tank was always rust brown, within a few days of a complete drain and refill. On the XJ6 however, the coolant is always clear and nicely green in its tank. Or should I just crack a hose and drain some out?

 

Well the XJ6 has an aluminum coolant rail and plastic header tank. The V12 has partially steel coolant rails, a steel balance pipe, and a steel header tank. Lots more stuff to rust.

You should try to flush til its clean obviously, but the way to prevent this in the first place is to change coolant regularly. If you aren't sure if its time, then just do a simple electrolysis check!

Switch a voltmeter to DC volts, stick one probe onto a good ground and the other probe into the coolant. Anything over 0.3V and you need to change out the coolant!

 

Thanks.


A great check. One of my steeds show some of the FE02. The other not so much.


Each enjoys an all FE engine.


Carl