running hot , fan clutch problem ?
 

hi all , got a small problem with my 1972 240z , recently when driving hard the temp gauge needle moves a little towards the right/hot side of the temp gauge , normally it sits bang in the middle under all driving conditions , as soon as you slow down and are useing less revs the needle returns to the middle of the gauge ? it is ok when ticking over needle in middle of gauge , could the fan clutch be bad and not be "locking up" to provide more cooling at higher tempretures

Re: running hot , fan clutch problem ?
 

there's also the potential that your t-stat may be sticking open as well...



David
1TuffZ
zccr.net
https://www.zdriver.com/rides/spec/p...1016465706.jpg

Re: running hot , fan clutch problem ?
 

flush ur radiator collant and put some new stuff in.. i heard that this helps it

mine sit just below the middle, normal driving, but hard driving sits perfectly in the middle

<font color=blue>76 260z</font color=blue>
The NiteRider

Re: running hot , fan clutch problem ?
 

Too much coolant can sometimes be bad causing overheating. Thermostat could be stuffed. Could be air in the system or early Z's had some overheating problems because they used a 2 core radiator as oppose to the 3 core but I think a 72 Z would be ok.
Other possibility is the temp guage is faulty. The guages in the Z get more inaccurate as the car get's older.


Gavin,
Melbourne
Australia
73' Datsun 240z

Re: running hot , fan clutch problem ?
 

what the guys said about too much coolant and sticking thermostat is correct. Try those, they're the quickest and cheapest fixes costing you no more than 15 bucks total.

if that keeps happening, see if you can find a fan shroud off a 280z to fit on the radiator. heat dissipation from the rad was also a big problem.