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good point i thought about that i used the fan from the 89 motor, but im almost certain i used a 85 fan clutch. they are different i looked them up at advance auto website. the 89 turns counter clock and the 85 turns clockwise. can i just have someone bump the key and see which way it spins to tell me what fan clutch i have on there?? also i was looking at a flex fan advance sells. its 19 inch fan and i do believe it eliminates the clutch just have to get a spacer. what do yall think about using one of those instead of playing the guessing game with the clutch? the fan is made by imperial
I have had the aluminum flex fans fly apart on me, and several other people I know have also. I have never tried a steel flex fan. I can also tell you the aluminum one I used was noisy. It made a high pitch whining noise.
I would recommend staying with a clutch fan, from my experience they are the best. I too have had flex fans fall apart and they don't cool down the engine very well.
good point i thought about that i used the fan from the 89 motor, but im almost certain i used a 85 fan clutch. they are different
It must help out by changing if the clutch is the wrong rotation at present......but are you SURE that the fan is the correct rotation (pulling air back, not pushing it forward)?
The reason I ask again is that I can run with no fan at all on my truck, & it cools perfectly just with the air flow from the forward motion of the truck - as long as I don't have to stop or get caught in stop/go traffic.
I don't normally run with no fan but a few weeks ago I discovered that the fan & clutch were heavy-duty, aftermarket add-on's that were costing a lot of power (7 blade fan & almost no-release clutch), so I was experimenting while I changed back to stock parts - made a noticeable difference to power.
Watching the fan while the motor is cranked won't tell you much - the clutch will still turn the fan even if it's the wrong one. It just won't drive it properly under load.
well does anyone know if there is a difference in fans from a 89 with a serp belt sys and a fan from a 85 with a v belt. the clutchs are diff and i would assume thats why. one clutch spins the fan clockwise and the other counter clockwise, correct?? theres gotta be a way to tell which direction its supposed to be spinnin
Of course there's a difference... one spins one way, the other spins the other way; therefore,
the blades on the fan have to be oriented in the correct fashion to suck air as opposed to
blowing it.
Easy way to tell if the fan is for a reverse rotation. Start the engine up, and see if it's pulling air thru the rad, into the engine compartment, or trying to push it thru the rad, and out the grill. If it does the latter, no air can move thru the rad while moving, as the forward movement of the vehicle causes the air to fight against the fan pushing.
Standing in front of the truck, looking down at the end of a blade, If the edge closest to the radiator (leading edge) is to your right, that is a V-Belt fan, if the edge closest to the radiator (leading edge) is to your left it's a serpentine fan.
festus great tip. i do have a serp belt fan on there for sure then. the fan clutch is right for an 85 v belt syst but the fan is not. now i got a flex fan although many you said not to i really dont have a choice as the fan is the right one i gotta give it a try. my question is i have the right fan we measured it, and it seems i have the right spacer. its a 2 inch and everthing there seems to be ok but how it attaches is where im scratchin my head. You have to remove the 4 water pump pulley bolts correct? if so i did that and then when you go to put the spacer on is it supposed to fit over the nose of the water pump (threaded part fan clutch screws onto) or sit flush because mine sits flush and the bolts are not long enough and even if they were how would i keep the water pump pulley tight?? anyone ever put these fans on a str8 6 before help me out. or cant they be put on???
Assuming you have the correct fan and such for your setup, have you covered the basics? You said you replaced the head gasket? Why? Did you ensure the block and head were perfectly flat? What is your initial timing set to? Is it advancing properly? Is idle mixture set properly? What is the compression on each cylinder?
cadunkle based on the info on here i have the wrong fan. im going to go with that for now. I replaced the head gasket because everything else was replaced. and that was what was left. when i had it apart i cked the block and head with a str8 edge and feeler. seemed ok compared with the specs in haynes manual. Im just waitin for someone to shine some light on this flex fan installation on a 300 6
What is your initial timing set to and is it advancing? Compression on each cylinder? Your fan sounds like a standard rotation fan. Does your belt drive the water pump pulley from the top or bottom? Is it driven off the crank pulley from the top or bottom?
If you have the fan clutch that threads on the waterpump shaft, you probably cannot use the flex fan. If you do a web search, possibly someone makes an adapter, I am not sure.
I confess I read all the previous posts in this thread a couple of days ago, but have forgotten and am now too lazy to look, but what waterpump do you have on there now. I am suspicous. If the reverse rotation fan fits the waterpump you have now, does than mean you have the reverse rotation waterpump on there too? That's not good either. What made me think of that, is I thought you may have a old waterpump laying around that didn't have the thread on clutch. Your flex fan should fit the older style bolt on clutch waterpump.
To install a non-clutch fan, remove the studs that the clutch mounts to, and use bolts thru the fan, then spacer and pully, threading into the water pump hub.
2" spacer usually needs ~2.5" long bolts. The studs are 5/16", and should have fine thread on one end and course on the other. I can't remamber 100%, but it seems like the course thread goes into the WP hub.
This is assuming it's not the clutch that threads onto the water pump.......
my fan clutch threads onto the water pump. and the fan clutch and water pump are correct for 85 model with v belt setup. the reason i had a serp belt fan on there was i left a rachet on the crank bolt when i was setting the timing and started it and bent the fan. so i had an extra not thinking anything of it figured it be the same. thats why the fan is wrong. but ya i made that mistake when i put the motor in of putting on the wrong pump. I figured an 89 motor i'll just get a 89 pump. ya i learned that one the hard way. so that has already been corrected with the right one. But im curious now to see if i can bolt my flex fan to my clutch the same way as my factory fan would have.