Fan Clutch info

[A31PKG]

Since 070 fan clutches do not grow on trees, I went to the Hayden web-site and looked through their on-line catalog. After spending considerable time going through all of their specs & measuremants, I came up with the closest match to the 070 with part number 2705. Auto Zone has it listed for $29.99. I will be ordering one today and let everyone know the outcome. Note that it is a Thermal unit, whereas the originals were non-thermal. The ones that are listed in their catalog to fit the b-bodys are actually too tall... My measurement of an original put the fan mount height spec at 1 1/4"... The ones they have listed as fitting the b-bodys have a minimum measurement of 1 3/4"... I found the 2705 to have the same dimensions but with a fan mount height closer to O.E. at 1.53"...

This particular one is listed as fitting an AMC Pacer! Well, being a closet AMC-guy, I can live with that....

 

[69hemibeep]

You might also look at the Hayden 2765 It is supposed to fit.

 

[A31PKG]

I purchased the 2765 but the flange diameter is too small at 2.32"... While tightening the flange bolts, they started "walking" out of their slots! The 2705 that I mentioned is closer to the pulley mounting surface diameter with a flange measurement of 2.6". This should provide plenty of support under the bolt head to prevent the "walking". I wish that Hayden offered a clutch with a captive hole like O.E. instead of the "one-size-fits-all" slots... BTW, if one is interested in the non-thermal part number, it is 1705 and Auto Zone has it for $19.99 ....

 

[ACME A12]

Most of the A12 guys run the 2765 if they cannot find an 070. Not sure why this did not work for you...???

Bob Schirmer of Glen-Ray Radiators recommends the #2765 (7.25" dia.) or a #2665 (6.0" dia). This infor was excerpted from a post on the LOH Playground.

070 fan clutches do not grow on trees...but once in a while some lucky guy digs into a pile of his old parts and finds one at the bottom of the bin...

:jester:

 

[69hemibeep]

Most of the A12 guys run the 2765 if they cannot find an 070. Not sure why this did not work for you...???

Bob Schirmer of Glen-Ray Radiators recommends the #2765 (7.25" dia.) or a #2665 (6.0" dia). This infor was excerpted from a post on the LOH Playground.

070 fan clutches do not grow on trees...but once in a while some lucky guy digs into a pile of his old parts and finds one at the bottom of the bin...

:jester:

I'm in the process of cleaning mine up and then a test drive to see if its OK.

 

[A31PKG]

Bob was the guy that originally recommended the 2765 to me. Unfortunately, the base diameter is simply too small. It jives with the measurements provided in the Hayden catalog, so I know it was not boxed wrong. I believe that if the A12, Hemi, A/C, & Axle Package folks look through the Hayden on-line catalog, all will agree that the base is off by at least 1/4" on the 2765... This is not only compared to the 070 dimensions, but if you hold it up to the w/p flange it is too small... If I get some spare time I will try to provide a pic or two...

Here's a link to the Hayden on-line catalog...

BTW, If anyone has an original 070 fan clutch and would be kind enough to post the dimensions, that would be great!

http://www.haydenauto.com/upload/Hayden ... clutch.pdf

 

[69hemibeep]

I'm happy happy happy. I paid allot of money for my 070 clutch in Vegas a year ago, actually my wife bought half since I had no work at the time, but I detailed it up and test drove it and it works, on a warm day to boot :banana: :banana: :banana: I do spy some rubber on my water pump I threw a belt at 6800rpm about a month ago :basketcase: Its 1 1/4 inches from mounting surface to mounting surface and 7 1/2 " across the face,any other dimensions you need?

 

[A31PKG]

Thanks Hemi - very nice mill you have there!

The 1 1/4" fan height measurement you provided backs up what I've read. The diameter of the flange base would be nice to have if you could swing it! I suspect it is in the 2 1/2" range. Unfortunately, none of the Hayden clutches listed have both the 1 1/4" fan height AND a 2.5" flange base.... The closest one would be the either the 1705 or 2705 .... both with a 1.53" fan height measurement and a 2.6" flange base.

 

[69hemibeep]

Thanks Hemi - very nice mill you have there!

The 1 1/4" fan height measurement you provided backs up what I've read. The diameter of the flange base would be nice to have if you could swing it! I suspect it is in the 2 1/2" range. Unfortunately, none of the Hayden clutches listed have both the 1 1/4" fan height AND a 2.5" flange base.... The closest one would be the either the 1705 or 2705 .... both with a 1.53" fan height measurement and a 2.6" flange base.

It is a 2.6" base!

 

[A31PKG]

Thats what I'm looking for!

BTW, Is that a Quanta repo belt? If so, you are not the first to throw one... It seems they are great for show and cruising, but don't hold their shape well under pressure...not sure what the deal is...

Thanks for the measurements!

 

[69hemibeep]

Thats what I'm looking for!

BTW, Is that a Quanta repo belt? If so, you are not the first to throw one... It seems they are great for show and cruising, but don't hold their shape well under pressure...not sure what the deal is...

Thanks for the measurements!

It is a Quanta, a new one, the other one didn't stay on worth a crap.

 

[EastYorkRunner]

Thanks for the info here. Ran into the same problem.

 

[ACME A12]

Thanks for the info here. Ran into the same problem.

You sir, have just earned the instant respect of all of the senior members on this forum by simply using the search function and finding the info you need rather than just blindly throwing a question onto the wall just to see if it sticks... :worship: :worship: :worship:

Keep up the good work. :cheers:

 

[steverino]

I have been researching this fan clutch deal and am wondering how close the 2705 clutch comes to the radiator ?
I don't think I have any more than 3.25" from the water pump pulley to the radiator.

So I am wondering if anyone running the 2705 (or 1705) clutch could tell me how much clearance between the clutch and radiator they have ?
Or I'm even curious how much clearance between the radiator and an 070 clutch there is ?
I don't feel comfortable with only .25".
Could it possibly be due to me having the 22" radiator rather than the 26" ?

I may end up having to try the 2765 since it is about .5" shorter overall .

The info here was a great start for me to narrow down my options, thank you

I have installed the 2765. 2705 wouldn't fit , was touching the radiator. Appears that the 22" rad is thicker for certain than the 26".
I agree the circumference of the mounting base to the water pump is not quite ideal, and could be bigger, I think that as long as the centering pilot bushing that comes with the 2765 is installed, the mounting is secure, but i'll be keeping a close eye on it for the first few hundred miles !