should fan spin with belt on?

mob

the guy who hits on his mom
20+ Year Stangneter :roc</strong><span class=
Oct 3, 2003
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Dallas, TX
I am having overheating problems, and I have a belt driven fan. I just realized that the fan spins even with the belt on. It spins very freely, and the belt is tight. Just the fan spins the water pump pulley doesnt spin with it. Is that normal? I am trying to diagnose my cooling problems and maybe this is a real dumb question but it seems like the fan shouldnt spin with the belt on, or else when the engine is spinning its not really turning the fan right? If it shouldnt turn what is it thats wrong? fan? Water pump? Clutch?
 
its normal for the fan to spin at all times when its running... but if the fan clutch is going it wont spin like it should and cause over heating problems... try spining the fan blade with the engine off and see how stiff the clutch is.. if there is no stiffness and the fan has no drag on the clutch then its going out...
 
So its normal for it to spin with the engine off when the belt is on? When the engine is warm I can spin the fan (engine off, belt on) very freely, if I "throw" it, it spins about 3 or 4 times.
 
K cool, I was hoping it was my water pump so I know for sure its bad. I also got a loud squeak when my car is cold. And also my power steering goes stiff some times, might just be low on fluid though. I guess this weekend I'll change the water pump and fan clutch. I am still loosing coolant from somewhere though.
 
are you have problems like sitting at a stop light at idle? if so then when your at idle the fan clutch should grab the fan and hold it al the way. usualy when your going down the road at freeway speeds is when he fan clutch starts to slip alittle bit so the fan dont always have to spin fast. its a way of freeing up hp instead of using a fan with no fan clutch. if it spins 3/4 times like you say then its a gonner, you will will some drag on it when you spin it by hand. like i said it will cause overheating isues because it s not pulling enough air through the radiator like its sapose to if its constantly spinning freely at idle. I hope this helps.
 
It's hard to tell exactly what its doing, I'll drive it for about 3-5 miles and the temp will just start to go up while driving and stay there, itll go up to about half way and sometimes itll shoot up to 270 or stay up around there. It will come down a little when I come to a stop or slow down, but it still runs hot. Its hard because I have a leak somewhere and I am losing coolant, which really makes it over heat once I start running real low. I am hoping the water pump is leaking and that will fix it, but I havent seen coolant come out of the weephole.
 
It's hard to tell exactly what its doing, I'll drive it for about 3-5 miles and the temp will just start to go up while driving and stay there, itll go up to about half way and sometimes itll shoot up to 270 or stay up around there. It will come down a little when I come to a stop or slow down, but it still runs hot.
I agree about the fan clutch but this also sounds like air is in the system.
 
Well its been doing this for a like more than a week, i dont think a bubble would stay in there that long, i'll burp the system after I do the water pump though. I've tried pressure testing it and I cant find where its leaking.
 
It could also be that the radiator is getting scaled up and full of corrosion/rust. I replaced damn near every part of my cooling system and flushed the coolant out several times over on my '84 before I finally figured the radiator was the source of my problems - dropped in a 2-core replacement and ta-daaaaa, runs perfectly cool now. :nice:
 
Well I lied, I check it today again with light out and it spins half a turn. I still bought a new clutch anyways, it is getting hot at higher rpm's and speed, I am hoping changing the water pump will fix it.
 
At higher RPM's and at speed, your fan pretty much does nothing - at that point, it mostly comes down to your radiator, coolant quality, and/or your thermostat. If your t-stat is too restrictive or not opening/closing properly, if your radiator is plugged up with scale/rust/stop-leak, or if you've got too much antifreeze and not enough water in your coolant, you can tend to run too hot.

Just a side question, is the air dam in place under the radiator? Not having one there can have a BIG effect on your cooling abilities, especially above 45 MPH.
 
I have a brand new mr gasket 180 in there, and yes the air dam is in there. I am going to swap out my radiator because it has a lifetime warrenty and see what happens.
 
I got the 3g on already, I am going to get an electric fan soon though and run a thermostatic switch. I dont think the fan is the problem though.