Coolant Temp Warning - pegged to red. Holy crap.

[andrewwynn]

It's not an air trapped thing. If the electric fan kicked on indicates that the output temp is hot and registering.

I'll bet on the t-stat


Sent from my iPhone using Tapatalk Pro

[Oldmactech]

Yes, my sons z-3 would heat up in traffic, viscous fan clutch had very little “bite.”


Sent from my iPad using Tapatalk

[Meestahbig]

I am getting confused, viscous fan, engine fan and electric fan? I am talking about the giant fan directly in front of the radiator, the one I have to take the blades off and remove the housing to work on things. I think this is the viscous fan/clutch.

My current guess, is that this is going. Rationale is its blowing weak, so if it blows weak cool air, things are stable, if its blowing weak hot air, then the coolant starts to overheat. Or the t-stat is restricting flow and again the warm air is just not sufficient with the weaker.

I'' get to work and report back with the solution.

[Oldmactech]

Originally Posted by Meestahbig

I am getting confused, viscous fan, engine fan and electric fan? I am talking about the giant fan directly in front of the radiator, the one I have to take the blades off and remove the housing to work on things. I think this is the viscous fan/clutch.

My current guess, is that this is going. Rationale is its blowing weak, so if it blows weak cool air, things are stable, if its blowing weak hot air, then the coolant starts to overheat. Or the t-stat is restricting flow and again the warm air is just not sufficient with the weaker.

I'' get to work and report back with the solution.

The viscous fan clutch is the center part of the spinning fan with blades. As the temp increases the fan spins at a higher rate as the viscous materials tightens the hub. When you first start the car cold the fan sort of lopes along, once the temp rises the clutch “ bites” more and the fan spins higher pulling more air over the radiator and increasing the cooling effect.

These thing fail so that if it doesn’t tighten enough the fan doesn’t spin fast enough. Usually in bumper to bumper traffic. But, never seen one fail to the extent you would get a quick over heat.

To test carefully stick a bit of rolled up newspaper in the fan after its at op temp. Ease it in. If the newspaper causes the fan to stop or even slow significantly the clutch is bad.

Safer way is with the engine hot but off try to spin the fan by hand. If the fan spins then the clutch is bad. If it resists, not your problem.


Sent from my iPad using Tapatalk

[Overboost]

Originally Posted by Meestahbig

I am getting confused, viscous fan, engine fan and electric fan? I am talking about the giant fan directly in front of the radiator, the one I have to take the blades off and remove the housing to work on things. I think this is the viscous fan/clutch.

My current guess, is that this is going. Rationale is its blowing weak, so if it blows weak cool air, things are stable, if its blowing weak hot air, then the coolant starts to overheat. Or the t-stat is restricting flow and again the warm air is just not sufficient with the weaker.

I'' get to work and report back with the solution.

Yes, confusion for sure. On the 3.0L M54 engine the fan in front of the radiator is the electric fan used mostly for A/C operation. Behind the radiator attached to the engine is the viscous fan. If you didn't hear a jet engine when your X was overheating, your viscous fan clutch is bad. Believe me, you can hear it when it is functioning. That fan moves A LOT of air when the clutch is engaged.

[Oldmactech]

Indeed loud and windy if you open the hood.


Sent from my iPad using Tapatalk

[Overboost]

Originally Posted by Oldmactech

Indeed loud and windy if you open the hood.


Sent from my iPad using Tapatalk

Loud and windy sitting in the driver's seat with the windows up and A/C on full song. But then I listen to every little sound my ole girl makes...

[wpoll]

I'm about to replace my viscous fan clutch - it works correctly but the bearings have shat the bed... :-(

https://youtu.be/kdhRraCZorA

Got a Hella Behr (OEM) unit for a decent price in the UK.

[Meestahbig]

done, ordered a new fan clutch... if that doesn't eliminate my issue as we head into summer, I will change out the thermostat again, not a big deal. I like that I can work on this car, makes it kind of fun for someone who is inclined. I really need to get in ad do my valve cover gasket and the intake boot. thank all. I will report back.

[Oldmactech]

Intake boot is way harder than it looks. Mainly due to the Metal clamps being hard to get a tool on.


Sent from my iPad using Tapatalk