Cold Starts

[trel]

Hey guys,

I have a 97 gts-t and about a week ago when I start my car cold the fan on it blows like crazy and you can see/hear it going real fast. Is that normal? I'm thinking it may be a dodgy coolant temp sensor, my only reason in saying that is because I am starting my car dead cold and fan runs like crazy maybe thinking its hot?

Cheers.

[gtst7]

Think your radiator clutch fan has locked itself up, I had the same problem a while back. Here's what greg told me

"Sounds like the fan clutch has locked up, that's if it's a belt driven standard fan unit.

Certainly NOT normal and will disintegrate the fan if you leave it like this.

The fan clutch is designed to slip so the fan NEVER goes above about 3000rpm. If the fan clutch seizes, then the fan will rev way over its designed limit and then they just fly to bits, usually wrecking the radiator at the same time.

You should be able to grab the fan blade with a cold engine idling and it will slip in the fan clutch. I don't suggest you try this, but that's what you can do when it's working properly.

Obvious tell tale signs from a seized fan clutch are the huge fan noise, like a jet taking off and very poor fuel economy as the fan will now be drawing lots of power.

With a hot engine, not running, the fan must be free to rotate by hand. If it's stiff, grabs or make grinding noises, there you go.

Greg."

[trel]

Hmm. That makes a lot of sense. It only does it though for about 10 seconds and yeah sounds like a jet when you first start then goes away. I'll try rotating the fan after a long drive and the car is hot (while the car is switched off this is lol!) if it spins freely then what else could it be?

Also if the fan clutch has seized, what do they cost to fix?

[trel]

Anyone know if an RB30 fan clutch assembly would suit the rb25? Does it need any modification to fit?

Cheers.

[NateR33]

pick a rb25/20 one up from a wrecker for about 50 bucks not worth modifying a different one