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SS Shaun
10-18-2012, 01:11 PM
so a friend of mine came on the house a few weeks ago and he gave me a list of things i needed to complete before i can start my car. i am on the second to last thing on his list and thats the fan. I was going to put in an e-fan but after talking to my uncle and another car guy friend of mine they both told me forget the e fan and run a fan off your water pump. here are the reasons given to me
1) e-fan draws a lot of amps at start up of the fan.
2) I would need to get a high amp alternator
3) they can fail on you much quicker then a manual fan

so after talking to another chevelle owner he told me to get a fan with a fan clutch and set it and forget it. so i ask you guys what fan should i look for and what fan clutch should i look for? and do you agree on the three things stated to me about using E-fans

Hank70SS
10-18-2012, 02:51 PM
A factory type setup, fan, clutch and shroud will do the job. Yes you'd probably need a new alt along with relays to power the fans and temp sensors to turn them on and off.

Not sure what fan was stock on a 69 big block. 70's used a GM xxxxx772, don't have the full GM # handy but everyone refers to them as 772's. Along with a Hayden hd clutch and stock shroud will keep your engine running cool if the rad, water pump, etc are all good.

carpoor
10-18-2012, 03:31 PM
The fan blade you want is a 3947772, and the clutch you'll want to use is a Hayden part # 2747 HD unit. It will will run nice and cool, plus damn near last forever.

Hank70SS
10-18-2012, 06:04 PM
The fan blade you want is a 3947772, and the clutch you'll want to use is a Hayden part # 2747 HD unit. It will will run nice and cool, plus damn near last forever.

Thanks, didn't have the numbers handy.

You can find the 772 fan on ebay. If you don't care about date codes they're not too expensive, mine is a 1973 fan. I replaced a flex fan with a 772 and the Hayden 2747 clutch.

carpoor
10-18-2012, 06:45 PM
Just purchased both for my heap, so it was fresh in my mind.