I am getting varying readings on ohmmeter between body of my XJR-S and new cooling system hoses. No reading from older original hoses but all of the new are giving me signs of continuity. System is still dry and radiator is brand new aluminium.
Has anybody ever come across conductive rubber before?

 

There is such a thing see (see link below). Why the new hoses exhibit the properties you are finding must be the difference in the hoses ingredients.

Conductive Rubber -what it is and where it?s used- | MAJR Products

 

do your hoses have a small red stripe on them?
the ones here that I have used in the past (20 some odd years ago)
the conductive ones had a red stripe down the length...

 

Yes, some rubber is conductive. It believe it depends on the carbon content. Most windshield washer hose is conductive, fuel hose usually is not. I have not checked a lot of radiator hose. I do not think it will be a problem but I might test for voltage in the coolant, that can lead to electrolysis, corroding the metals. I would think conductive hoses would reduce the voltage, but again, I have not looked into conductive coolant hoses.

 

I would much prefer to run the radiator as an isolated unit rather than ground it in the fight against any possible electrolysis but not sure I can do that now if the hoses in effect ground it anyway. I will check the actual stray current situation when I get to that point in the build.

 

Electrolysis needs a potential difference to work so as Dleit53 said, it could only be a problem if somehow there was a voltage between the water and the chassis.

I have a hard time imagining how that could happen since the radiator is bolted to the chassis, and the block is bolted to the chassis, so they are both at the same potential (i.e. grounded).

That the rubber hoses are somewhat conductive (the water inside them surely is much more conductive) will not cause electrolysis on its own.

 

The radiator is NOT bolted to the chassis, it is mounted top and bottom in rubber grommets and should in fact be isolated from the chassis/ground.Even the bleed pipe and fan shrouds are arranged in such a way as to keep it isolated. There seems to be ongoing debate about whether to isolate or ground as a means to minimise any electrolysis, I lean toward the isolate.

 

Just purchased 89'XJ-S without brake. I am new and going to need a lot of help..