Faulty Clutch Fan..

[Gazee]

Hi Guys,

I've searched on here for some answers to my problem with my R33 S2 Manual RB25DET.

My water temp gets to around the 95-97 degree mark normal driving (even highway) and with air con on it comes up to around 107+ degrees...

I'm wondering why it might be doing this, On the dyno on a 25 degree day, the tuner at chasers noticed the temp creeping to around 95 degrees so he stopped and checked why not enough air flow was getting to the radiator.. and he mentioned that my clutch fan might be not engaging correctly..

During the colder months of the year my temp shows aorund 80-85 on the Power FC but this is starting to worry me and being lazy I havn't done much about it...

Any help or input would be great before I start spending money on things that don't even help... (which has been done many times before)

Also I'm wondering if anyone knows how to check for a fault clutch fan because i'm planning on doing that next to see if it makes a difference...

I noticed after the turbo was installed the engine bay was getting noticeably hotter but I figured being the size it is that would be normal...

Thanks in advance!!

George.

[76GTR]

Hi George, What condition is the radiator in. if the radiator has not been cleaned out or replaced over the years the cooling tubes in the radiator become blocked causing low flow inside the radiator. The radiator acts like a filter for the cooling system. Also check the front of the car where the air goes in, between the a/c condensor and the radiator for obstructions. If the temp is getting that high the viscous fan should cut in. The amount of air flow going through the radiator at highway speeds is quite a fair bit, but if there is a blockage internally or externaly is system won't be able to cope. i would get the cooling system checked by a mechanic or a cooling specialist.

Regards

Clynton

[GTR-N1]

Usually, if the fan clutch is faulty or leaking, the water temp starts to rise alarmingly if you're standing still. And then it goes down again after moving off.

So if you've got old coolant in the radiator and sludge or corrosion, Clynton may be right above. All JDA imports should have the coolant changed after new ownership.

[some_cs_student]

When clutch fan is warm (water temps above 60 or 70 degree) it should "lock" with the engine spinning upto a certain RPM.

So when you turn the car off it should stop spinning very quickly rather than free spinning for a long time (it will free spin a bit when cold).

Also, when warm if the clutch fan starts moving (on startup) it will resist anything stopping it from turning with the engine, when my one was gone you could touch it with a finger and start the car and it wouldn't move (until it was replaced)...

[Gazee]

Thanks heaps for your input guys!!

I'll try a few of those things on the weekend hopefully its not too hot but at the moment its that hot in melb you can't even scratch your ass without breaking a sweat... dammit!

I was thinking maybe i'll take the radiator out and get it checked but there isn't any leaks the coolant level hasn't dropped and the thermostat is opening... i'll let everyone know how i go!

Thanks again!

[Guest 40th-edition]

Terry is right, it will only get hot wen stopped. the viscus set up in the fan i have seen lock so it is always noisy and very hard to turn when off.

if you have a big fmic like me they restrict large amounts of air flow over rad or thurmostat stuck probs worth changing only cheap. could also be blocked rad like the others said.

mine does the same thing only on over 40deg days so going to put a 3core rad in when i get some cash.

let us know how you go.

[Gazee]

Terry is right, it will only get hot wen stopped. the viscus set up in the fan i have seen lock so it is always noisy and very hard to turn when off.

if you have a big fmic like me they restrict large amounts of air flow over rad or thurmostat stuck probs worth changing only cheap. could also be blocked rad like the others said.

mine does the same thing only on over 40deg days so going to put a 3core rad in when i get some cash.

let us know how you go.

yea i see what your saying, i do have a large fmic and air flow is being blocked and it doesn't really lock up or anything when its pretty hot its easy to turn but not free spinning or anything... i'll flush out the radiator and give that a try first which i think might not really help lol but i think it might actually be the clutch fan playing up...

it spins only a little after the car turns off not immediatly, i checked today when the power fc showed around 90 degrees so maybe its that ey..

[Guest 40th-edition]

well is it over heating when you are driving cus if so then the ram air will cool, the fan is only being usefull when sitting still or slow speeds.

it should spin alot when turned off when cold and then drive and see if there is a diffrence.

the fact that it does it when it is hot makes me think airflow or rad blocked

[Gazee]

I just noticed the car was on 92 degrees (power fc temp) and when i jumped out the car turned off and span a bit after ignition was cut... wasn't an immediate stop or anything and it turns without much force needed either...

If it was the airflow (because of the fmic) everyone would have the same problem wouldn't they? well everyone with a similar setup anyway...

So you reakon I should just take the radiator to a place to get it checked before i do anything else?

anyone know any places to take it in melb western suburbs thats reputable? should i just take it off myself and take it to the place or take the whole car there?

thanks again for the input!

George.

[Guest 40th-edition]

if you want to get it checked pull it out your self, easy as. then you will know and change coolant when put it back in.

check your belt and waterpump when you are there. wp should be quite and belt should not slip.

dont know any places in melb

[Gazee]

thanks again mate

yea the water pump was recently replaced and the belts were done at the same time... i'm thinking more and more about not enough air not flowing through due to obstructions and considering my low mount GT 25/40 getting really hot that might have a lot to do with it also... i had a look and i have no idea what i can do to make sure enough gets through?

would a heat sheid on the turbo be any good? at the moment there isn't one on there but i'm just wondering if its going to help...

i ran it today in the 30 degree heat with the air con on and it didn't seem to go much more than around 96deg whilst driving according to the power fc.. but never has it hit near the H on the standard temp guage, just a touch above half..

[Guest 40th-edition]

yeah mine will only got to H when its about 40 and once its past half it starts moving fast.

i have thought about removing the little grill that ser2 have on them between the lights... give it a go next 40 day im driving.

rather than changing the fmic a 3core radiator might work better but more expensive than getting your rad cleaned.

keep me updated, Azz

[gotRICE?]

Forget the idea of "less airflow". It will be less, but it will be fine

There are a million people with huge thick FMIC's on their cars that dont suffer any cooling issues.

Think about the 100mm ones! They would kill a cooling system if they didnt flow.

Im going to go with either your thermostat isnt opening fully, or your radiator is blocked, OR your fan isnt engaging fully at idle.

In my R33 with Blitz LM FMIC, if i put my hand against the core at idle, you can feel the air getting sucked through your fingers, and its alot more than i expected!

A heat shield on the turbo would be a good bet. I didnt have my OEM one on for a few days when i was tidying it up, and the heat inside the engine bay at standstill was alot higher. The strut bar felt like it was going to melt untill i put it back on haha.

But in saying that, if the fan was spinning properly, then the air in the engine bay would be getting refreshed pretty quickly. Try the rad/thermo/fan.

[Gazee]

hello all... i've changed my clutch fan with another one from the wreckers and it seems to make a small difference (didn't cut the fan blades this time either) although still getting to the 95-96 degree mark in this shitty melbourne weather...

i'm about to do a cooling system flush and i hope that hits the nail on the head... if that doesn't work i think next step will be the thermostat but for the sake of my pocket i hope this fixes the problem lol

i will keep you all posted and thanks again for your help!

[some_cs_student]

Not cutting the fan blades might make a small difference too

The most common cause is radiator blockage, give it a good flush, there are a few threads with lists of potential issues (eg. water pump fins corrosion and others).

[Gazee]

yea very good point... i just did the flush on the cars system, couldn't get that f*kn bolt off on the side of the block tho so i just kept running some water through it, took it for a drive and then emptied it out until it came out pretty clean...

topped it up with nulon coolant and seems to be still creeping up around the 92ish mark even in this fresh wind we're getting in melbourne..

i think no flush that i do can get the crap out of the radiator if thats whats happening... looks like thats the next step for me, the blokes at the radiator joiint reakon $80 to get it tested and cleaned out which isn't too bad considering i've already spent $200 just today on sorting this sh!t out (to no avail)

even tho i've had my car for over 3 years and gone through heaps of crap with it i'm still a bit of a noob when it comes to the cooling system god dammit!

[Gazee]

ok now finally the problem is solved!!

the radiator was f*kd, it had a hole in the bastard which wasn't visible until you took it out (not to mention it wasn't using coolant!)... $380 later I got a new Koyo copper core radiator and now the thing doesn't budge over 83 degrees...

thanks again for everyones help... i should have checked that damn thing out to begin with!!

Cheers!

George

[Guest 40th-edition]

nice to hear, might pull mine out and get it checked.

[GTR-N1]

Yep good to hear!