One for us petrol heads

Talking to a chap about my woes with the gear box and we got round to talking about Jag motors as opposed to the Rolls royce and I thought it would make a good discussion here as many of you may have worked on both, Jags and Rolls.

So have I. I have always regarded Jag motors as "delicate". You may or
may not know the reputation of the V12 Jags from the 60s through to
late 80s? Lovely motor, went like a scalded cat - if you over heated
it, consider it scrap. Which was only made worse by the crap water
hoses, under sized radiator and all the other usual Pommie automotive
failings. Such that it was more a case of when you cooked it not if.

Your motor as far as I know is a down rated version with different
compression ratio, IIRC different head etc than the civilian motor.
The Fox is probably the least demanding of all the vehicles whether
civilian or military (think of the stresses in a CVRT or being
revved out and thrashed through the gears in an E type). So you are
ahead there, look after it and it should last.

I have not been able to confirm if the Fox/CVRT military motor suffered
from the propensity to drop cylinder liners the way the civilian motor
did. Indications are that it is not a failure mode that has come to
light, so that is good.

Stay aware of any oil in the water or water in the oil. Providing it
is caught early, the motor can be fixed.

Stupid design to have cylinder liners with no retaining lip. They were
just a sleeve pressed in. With piston ring forces and cooling and
heating they crept downwards. Incredible.


Cheers