soysauce300zx

Hi everyone, I have a 1986 300zx turbo and i think i have a problem but correct me if im wrong. With my car at operating temperature the coolant gauge needle is over the F on the gauge. I know my gauge is working because i have a laser temp gun and it coincides with the gauge. At one point i had the temp gun lazer on the thermostat housing and it was about 220-230 degree's Fahrenheit. It is about 90 degrees outside but i think that's a little high. I have burped the system and my coolant level stays were it needs to. The temp readings across the radiator are the same so i know its not blocked. I know the Thermostat opens around 180 190 when i checked. Also with my car up to operating temp when i rev the engine and let the RPM's start climbing i can hear the fan but around 2500-3000 RPM's i can hear the fan turn off or slow down dramatically, is this normal?

Another thing i am a little concerned about is i get a temp gun reading of about 130 when the lazer is point on the exterior of the turbo charge pipe and 140-150 at the intake plenum.

I dont know what to think so what do you all think about it. Thanks for the help i appreciate it.

rogerz

turbo is gonna be hot. your exhaust gas runs thru it. the air supplied to the engine is compressed and therefore will be hot. what fan are you talking about? I can't hear my fan on my 86 turbo. are you hearing the turbo spool up? Are you hearing the vacuum pump run? when the car is going forward at any normal speed more air goes thru the radiator than a fan can pull. Is your shroud in place - black plastic piece that funnels the air into the engine compartment. 230 probably about right that is where mine sits going 70-80 steady.

soysauce300zx

Okay that's good to hear as long as i know someones turbo z31 runs about that temp. I do have the whole fan shroud in place. Funny you say that because i just installed the fan shroud section a week ago or so. So I'm guessing your temp needle hovers a little past the F mark?

AZ-ZBum

The needle on the gauge of my turbo never ran over 1/2, even in the middle of the summer. I would suggest going through your system and just replacing the thermostat and radiator cap. to start.

rogerz

digi dash but 230 is about what the scale would be only shows 210 and 270 blank in the middle.

AZ-ZBum

Bottom is 120.
Top is 270.
Middle is 195.

Each segment therefore represents about 12.5 degrees.

230 would be about the 4th segment down.

If you're running 230*, you're running way too high.

SwarthyOne

with zbum on this one. '86 turbo and if my gauge goes over dead center, something's wrong. have you flushed your coolant? i had to flush mine around 7-8 times to get all the rust out. rust alone probably wouldn't cause your whole problem, but it wouldn't help.