Overheating issue :/

[kefferjoe]

So I ha e an 86 300zx and it overhears oh so slowly but it does eventually over heat I have replaced the thermostat and flushed the system but it still overheats very slowly and the thermostat was the more expensive one but it may be causing me issues still idk....any ideas?

[kefferjoe]

Oh and btw it holds at 170 which is where the thermostat is supposed to let coolant flow

[evildky]

radiator, they low angle mounted radiators seem to be mroe prone to catching debris and cloggine, it's fairly common

when you fill the system you do so wiht the heat on right? and the vac line going to the heater control vavle is workign right?

[kefferjoe]

I am pretty sure the vacuum line the the heater is working cuz my heater works fine ...is that a correct assumption??

[evildky]

generally but it's pretty simple to check for vac at the heatervalve, it' right next to the firewall and the hose is right on top

[kefferjoe]

ok well all of that seems to be working fine...could it possibly be the fan clutch causing this overheating issue??

[evildky]

when the clutch fails it generally lcoks up, most likely it's a clogged radiator, it's fairly common ont he Z31

[Meduza]

Check the ignition timing. If it`s to early the engine will be hot. I think..

[kefferjoe]

Wwll I hav flushed the radiator once already is it possible I need to do it again? And how would I check the igntion timing??

[evildky]

sometimes oyu just can't flush the gunk out and you have to replace the rasiator, it happened to both of my z31's