High rpm and stock fan & clutch
#1
High rpm and stock fan & clutch
I HAVE A 72' CUTLASS-S 442. IT HAS A BENT FAN BLADE ON MY MECHANICAL 6 BLADE FAN. THE 455 MOTOR HAS A FAN CLUTCH & FAN, BOTH FACTORY STOCK. I TWIST THE MOTOR TO 5500 RPM. ALL AFTERMARKET REPLACEMENT FANS I'VE LOOKED AT, ONLY GO UP TO 4000 RPM. IS THERE A WAY TO SAFELY "BEND BACK" THE ONE BENT BLADE? THERE'S NO SIGNS OF FAILURE ON THE STOCK UNIT. I KNOW THAT THE CAR, BEFORE I GOT IT HAD 350 MOTOR MOUNTS, WHICH "BLEW OUT" THE BOTTOM OF THE FAN SHROUD. EVERYTHINGS BEEN CORRECTED, BUT I HAD A NOISE COMING FROM THE FAN HITTING THE NEW SHROUD...BUT ONLY ONE BLADE IS HITTING. MOST LIKELY FROM TRYING TO OCCUPY THE SAME SPACE AS THE SHROUD....IS THERE AN AFTERMARKET UNIT OF EQUAL CFM? IS THERE A SAFE WAY OF REPAIRING THE BENT BLADE? YOU CANT SEE ANYTHING OBVIOUS LOOKING AT IT BUT THE BENT BLADE IS A HALF AN INCH MORE FORWARD THAN THE OTHER FIVE. WHAT DO YOU THINK??
#2
I run an aluminum flexlite up to 6k but it sucks on the street ( not enough cfm) im going to the stocker unit . I would put an ad on the wanted section and im sure someone will have what you need and a reasonable price.
#7
No name-calling on the forum, please - it's in the rulebook...
Some guys are too much into 'web etiquette'; just let 'em be...
If you have one blade that is bent on a factory fan blade, it can be straightened if not severe. Just make sure it was from physical damage (like shroud contact) and not metal fatigue. Inspect it well for cracks or other damage.
A proper fan clutch should disengage the fan at high RPMs so that it just freewheels. When freewheeling,t he blades will stay well under 4k.
Some 'heavy duty' clutches may try to stay engaged at higher RPMs, causing possible risk of failure.
Use a standard clutch instead. I had that issue (HD clutch keeping fan engaged at high RPMs) and backing down to a standard worked well at fixing that.
Heavy duties are better for trailer towing, city slogging, etc, where engine speed and road speed are fairly low.
Just make sure your shroud clearance is okay before running high RPMs again.
Some guys are too much into 'web etiquette'; just let 'em be...
If you have one blade that is bent on a factory fan blade, it can be straightened if not severe. Just make sure it was from physical damage (like shroud contact) and not metal fatigue. Inspect it well for cracks or other damage.
A proper fan clutch should disengage the fan at high RPMs so that it just freewheels. When freewheeling,t he blades will stay well under 4k.
Some 'heavy duty' clutches may try to stay engaged at higher RPMs, causing possible risk of failure.
Use a standard clutch instead. I had that issue (HD clutch keeping fan engaged at high RPMs) and backing down to a standard worked well at fixing that.
Heavy duties are better for trailer towing, city slogging, etc, where engine speed and road speed are fairly low.
Just make sure your shroud clearance is okay before running high RPMs again.
#10
Thanks "tru-blu442", and "Lady72nRob71" Sorry about the name calling, They weren't even helpful...just replied to complain...that set me off....
I was able to straighten the stock fan, and WAS going to use the "GM purchased" H.D. fan clutch, that has less than 1000miles on it....but there's a dirt trail down the fan blade and a 4" wide patch of dirt that stuck to the silicone oil that collected on the inside-bottom of the fan shroud. This is the 4th clutch i've installed on my car since I inherited it from my mother, in 1991. I found a severe duty Hayden unit #2797 on ebay for $30.00?? If it turns out to be bogus, well, the ebay "buyer protection" option WILL be used!! "Hey tru-blu442" can you send me an e-mail? just in case I'm needing your parts, your offer is very fair! rubberwrench@qwestoffice.net rubberwrench...I'm a 30yr. plumber....
Regards to all who replied!
I was able to straighten the stock fan, and WAS going to use the "GM purchased" H.D. fan clutch, that has less than 1000miles on it....but there's a dirt trail down the fan blade and a 4" wide patch of dirt that stuck to the silicone oil that collected on the inside-bottom of the fan shroud. This is the 4th clutch i've installed on my car since I inherited it from my mother, in 1991. I found a severe duty Hayden unit #2797 on ebay for $30.00?? If it turns out to be bogus, well, the ebay "buyer protection" option WILL be used!! "Hey tru-blu442" can you send me an e-mail? just in case I'm needing your parts, your offer is very fair! rubberwrench@qwestoffice.net rubberwrench...I'm a 30yr. plumber....
Regards to all who replied!
#11
If a clutch has signs of silicon leakage, then it is a gonner.
Rockauto has the standard thermal fan clutch for 22 plus 8 to ship - HAYDEN Part # 2705
The severe duty one you see might stay engaged at high RPMs like you do not want.
Rockauto has the standard thermal fan clutch for 22 plus 8 to ship - HAYDEN Part # 2705
The severe duty one you see might stay engaged at high RPMs like you do not want.
#12
FWIW, one of our other members (I believe AllanR) posted recently about a fan he restored. It wasn't anything too spectacular but he disassembled the fan and clutch, media blasted everything, painted it, and reassembled everything. It tunred out looking great. You might consider doing the same when you put yours back together.
#17
I had to replace my torque converter too! the stock unit "went away" I would be driving down the street and it felt like I had shifted into neutral and was coasting...
I upgraded to a B&M 2400stall 10" converter that was rated for use with "nitrous oxide" and WOW seemless shifts!! plus a B&M stage two shift kit, and you have an unbeatable combination for the street!
I upgraded to a B&M 2400stall 10" converter that was rated for use with "nitrous oxide" and WOW seemless shifts!! plus a B&M stage two shift kit, and you have an unbeatable combination for the street!
#19
I would take that heavy rotating mass off and go with a aluminum flex fan..if your taking it to 5500 your probably going towards 6000.. Mine winds up fast I wouldn't have a chance to see 5500.. Don't toss the original.. I have just flex no clutch.. 4 row stock non aluminum radiator.. Sits at 175 when it's 90 degrees.
#23
Belive it or not. I went from a flex fan with no clutch to a stock set up. The engine spun up way faster ! I talked to many guys about this. Moral of the story is the stock set up works great and when not engaged your engine will rev faster and there is no drag from the fan being engaged. The flex fan is engaged all the time. My only issue is by the time I hit 5500 rpm im tossin belts. I blame some pulley misalignment to that. As for going through clutches I'll find out I constantly beat the crap out of my stuff. There is no such thing as easy crusing for me.
#24
coppercutlass; Hello. I have a deep groove pulley designed for high rpm, on my alternator. I also have a monster tach with a shift light, set at 5500rpm because the stock tach is too hard to read when racing. early on after my engine rebuild, I happend to get a hold of a water pump that had a wobbily front pulley-fan mount. It was barely noticeable, and I thought it was the three groove pulley. It would throw the alternator belt at high rpm. the water pump was still under warranty.
#25
I fixed my tossing belt issue originally with a deep grove pulley set. now that I went to stock set up im back to square one. I think pulley alignment is my issue Which im positive it is. I also have a deep alt. pulley but the alignment is so far off and these v belts are like rubber bands at high rpm they just pop off. make sure you have the correct water pump and pulley combo. I went non ac alt set up and non ac pulleys I need to also use a short water pump. Im doing that next and if not im gonna have to use the under drive pulleys. I made too many changes to my cooling system. I think my issue was insufficient shrouding mainly. You might have a misalignment issue. I spin my sbo's up to 6k at the track on the street it get's hairy after 5500 rpm so I keep it to 5k if im beating on it.
Last edited by coppercutlass; December 23rd, 2013 at 08:15 PM.
#27
All my issues are fixed now. I went with a 7 blade, 18" fan. the pulley problem was fixed after I replaced the water pump under warranty. The old fan was a stock factory one, (as was the replacement) 6 blade, 19 1/2" unit. I'm happy to report that with the stock factory fan shroud, the 18" unit pulls plenty of air! There's no detraction from the 1 1/2" detraction. Situation solved!!! Thanks Everyone!.
Regards!
Regards!
Thread
Thread Starter
Forum
Replies
Last Post
SuperNovass
Parts For Sale
0
March 5th, 2012 09:19 AM