400fanboy

Had my shop replace the fan clutch as it had failed in the open posistion and was not spinning at all.

Now the fan spins 95% of the time. Even after 20 minutes of 80mph highway cruising when there should be PLENTY of air being shoved into the radiator, it's still spinning. Loudly. The fan is 1:1 matched to the engine RPM, so whenever I give it some gas and rev to 4000 RPM the fan gets loud as **** too.

Temperature needle in-car stays exactly where it should be. I haven't had any overheating issues even on the hottest days with A\C blowing cold.

This sounds like the new clutch was damaged? It seems to be frozen in the fully engaged posistion and is not slipping unless it fully disengages.

400fanboy

Bump. Brought it back to the shop - they told me they tested the voltage directly to the fan and the coolant temperature sensor. Both working. Said the fan was working as intended. That "maybe that's just how it is". "maybe it needs a lot of cooling". I pushed back saying no car should need it's fan spinning while cruising down the highway at 80mph.

They offered to RMA the part and install a new one, I declined for now since my trust in them is really degrading. I'd really like some more knowledgeable advice here to confirm my research that they might have ****ed up the install of replacing the part (or, the horror, they didn't install a new one and just fixed the old one).

Thanks!

oldskewel

iTrader: (1)

What year is your car? The engine fan clutch on my '91 does not have any voltage, for example. So I was thinking of things until you said "voltage" and then I realized yours is a completely different system from mine.

400fanboy

It's a 98, and I'm just repeating what the shop told me.I think it uses a viscous coupling which is a mechanical unit so that is an interesting point.

aptoslexus

I seem to recall that the fan will run at all times if the electrical connection at the radiator is not plugged in.

Michael88

I am confused. Are you talking about the fan clutch or the electric radiator fan? The fan clutch is behind the fan on the front of the engine, and the electric radiator fan is in front of the radiator. On my 98 if you unplug the wire atop the canister in front of radiator on the drivers side, then the electric fan will stay on. But a fan clutch between the fan and engine staying on all the time is likely due to being a heavy duty fan clutch, which an LS400 doesn't need unless you are doing some crazy towing.

Michael88

A fan clutch should not be making noise going down the highway. If it sounds like a freight train anytime other than sitting at a long stop or at start up for 5-10 seconds then it is the wrong fan clutch. Keep in mind the radiator fan is an entirely different cooling fan meant to assist particularly when the AC is running and might assist with engine temps in traffic on super hot days. The radiator fan is the only one with a voltage.

400fanboy

The plastic, electric fan infront of the radiator isn't the problem. It's the main fan which sits inbetween the radiator and the engine. It spins 100% of the time regardless of temperature or driving style and matches engine RPM 1:1. So when I rev the engine to 4000 rpm it's as loud as a big diesel truck.

It's a brand new part, was just installed by my shop. They're claiming it is working as intended.

I did some googling and either the spring which controls the engagement is broken (most likely), or a bearing in the unit was sized.

Electric fan spins right away on startup with the A/C on while the main cooling fan is blowing like it's life depends on it even with a cold engine.

cyfi66

Aftermarket fan clutches tend to operate like this. Get an OEM clutch or Denso clutch and it should work fine. Hayden/other aftermarkets are known to do this.

400fanboy

Who is OEM? AISIN?

https://i.imgur.com/RaLHCYo.png

cyfi66

Thats right I meant Aisin, not Denso.

timmy0tool

iTrader: (7)

the fan should run that way when parked and you looking at it since the ambient temp sensor within the clutch is engaged as there is no air rushing in.
it is pretty difficult to confirm if the fan actually stops while the car is at speed (but it should)! strap your phone or gopro into the engine bay and go for a spin?

400fanboy

It's clearly audible when you give it gas and it downshifts a couple gears, even at 80mph

spuds

Yep,thats just plain not right.I can hear mine just fine when it kicks in,and thats rare to boot.