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Please HELP - fan spacer to pulley to fan mounting trick with Rad still in

FWIW a clutch fan is easier to install (you can use a stud to align parts) uses less horsepower & makes less noise... B bodies have limited space so some fan clutches won't fit but the Hayden 2947 absolutely will fit..

Hayden 2947.jpg
 
I like the slotted holes. Those would have helped me a lot. Do you know the diameter of that fan and can you provide the Part # link?
Points of reference to what I did.....

My original thread on here: Cooling issues - and a weird question
The Summit fan I used: Allstar Performance ALL30100 Allstar Performance 6-Blade Fans | Summit Racing

For reference, the factory shroud on the 26" setup I used has a 20" fan opening; the linked to fan from Summit is 18"
outside diameter.

EDIT: All credit for my choosing that particular fan goes to member @coloradodave here on FBBO.
 
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I was told that the reason aftermarket radiators sit closer at the bottom of the fan is because stock radiator cores are wider at the top than the bottom.
It's actually because the engines do not sit "plumb" in the chassis, while the radiator and support...do.
I learned all about this during my trevails of "customizing" Fred's cooling setup (as linked in my post above),
with helpful folks clueing me in to what was happening at the time.
There's about a 1/2" difference from fan to radiator clearance, top to bottom...
Ma addressed it (sometimes at least) by making the shroud similarly thicker up top than at the bottom, for example.
 
I'm aware of the tilt of the engine. Measure a factory radiator and report back!

1 hmmmm.jpeg
 
Yep, that's the one I tried at the time....no dice, too close for comfort for me with the Griffin.
Wound up with a direct drive fan (see my other posts) and a simple 1" spacer to get the fan blades
pretty much half in/half out of the NOS shroud I was (still am) using.
You know what? A few years later and I can report zero issues from doing so - not so much as
additional fan noise or anything, at least up to about 5200 RPM (that's all I'll spin this raggedy ol'
440 to, anyways :)).
 
Yep, that's the one I tried at the time....no dice, too close for comfort for me with the Griffin.
Wound up with a direct drive fan (see my other posts) and a simple 1" spacer to get the fan blades
pretty much half in/half out of the NOS shroud I was (still am) using.
You know what? A few years later and I can report zero issues from doing so - not so much as
additional fan noise or anything, at least up to about 5200 RPM (that's all I'll spin this raggedy ol'
440 to, anyways :)).
I think you might be mistaken, previously you said you'd tried the Jag clutch which was the popular choice prior to the release of this new unit, it shares the short shaft with the 2947 but has taller cooling fins....
 
Tell ya what....if you're all that damn curious about it, YOU measure one and report back....biyotch!
:rofl:
I was told that the factory "wedge shaped" radiator core was designed to compensate for the angle of the engine and fan.
The radiators I have our back show it is the brackets that differ.
Bottom shows 2 7/8”.

21C42668-9C4D-405B-A495-CC7A0806C453.jpeg


Top shows 3 1/4”.

DD26D80A-C5B5-4126-A91B-FB88B4794B4B.jpeg


I measured two others. One of them shows a difference from top to bottom, another is the same top to bottom.
From what I see in this extremely narrow research effort, the core support is plumb, the brackets that mount the radiator tilt the top back a few degrees in some/most cases.
 
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I think you might be mistaken, previously you said you'd tried the Jag clutch which was the popular choice prior to the release of this new unit, it shares the short shaft with the 2947 but has taller cooling fins....

I think you might be mistaken, previously you said you'd tried the Jag clutch which was the popular choice prior to the release of this new unit, it shares the short shaft with the 2947 but has taller cooling fins....
Last time to answer this one.... this is the exact unit I originally tried to use, verified according to researching my own
purchase history
of some years ago at Summit:
Hayden Automotive 2947 Hayden Fan Clutches | Summit Racing

Any further information "required" can be found in my thread at the time, which I've already linked to in a response above.
 
I had a hard time getting the hardware installed with that stubby 2947.....and gave up. I bought some NAPA house brand that was slightly longer but still allowed 3/4" clearance at the bottom.
 
I was told that the factory "wedge shaped" radiator core was designed to compensate for the angle of the engine and fan.
The radiators I have our back show it is the brackets that differ.
Bottom shows 2 7/8”.

View attachment 1317939

Top shows 3 1/4”. View attachment 1317940
There's that "approximately 1/2" I was talking about....

Similarly, I did write the following in the response above that apparently got your attention:
"Ma addressed it (sometimes at least) by making the shroud similarly thicker..."
I said so because the NOS 4-hole factory shroud I purchased at the time is noticeably thicker at the top
than at the bottom, as I imagine many of the day were...

Further, in this very thread I believe, someone else asked the same question I did back at the time about the
stand-off the top of the factory shroud has built into it, namely, "should I seal up this gap across the top of the
shroud?"

(My answer eventually was to leave it as it was, thinking Ma had reason for it to be there in the design).
 
Are you sure??? :poke: :poke: :lol:
*snicker*
It got TIGHT with the Hayden, man....a 3" thick radiator will do that to a fella.
Images of grinding a huge circular hole in a brand new $600 radiator dancing in my head...
 
SUCCESS! I've got the fan mounted back in and it was so easy.I woke up in the middle the night last night and suddenly thought of using a wooden chopstick. Then I read Turbine68RT's golf tee suggestion which is similar. Good thinking! The key is that the chopstick is not threaded and it's just small enough to pass through into the bolt hole. I cut it long enough to clear the pulley/spacer/fan arrangement with 1" sticking out. I only needed one wooden cut chopstick piece to support one water pump flange hole with the pulley/spacer/fan arrangement oriented at the 12 O'clock position. Then I was hands free to thread in the other 3 bolts. I then pulled the cut wooden chopstick out halfway until it ran into the radiator, then cut it in half with some large wire cutters, then pulled the remaining chopstick piece all the way out and installed the last bolt.

So the process is:
- Flat carboard piece in front of radiator face to protect it and your knuckles
- Orient Water Pump 4-hole flange with one hole at the 12 O'clock position
- install the single groove water pump pulley by first angling the top back to allow the pulley bottom to clear the crank pulley
- Cut wooden chopstick 1" longer than water pump bolts and insert through pulley/flange into the 12 O'clock hole. Rotate pulley slightly as needed until hole is aligned to accept wooden piece. Now you're hands free.
- Feed spacer/fan as one unit over 12 O'clock position wooden chopstick piece and water pump flange center hub
- Install other 3 bolts half way (1st bolt don't rotate fan, but after first bolt, you can rotate to install next 2 bolts)
- Remove wooden chopstick piece halfway, cut end off while leaving 1/4" to grab, then pull remainder out
- Install last bolt
- Don't be afraid to jiggle pulley back and forth while starting each bolt until all 4 bolts are in. I also found once the bolts were started, it helped to use a socket held with my fingers to get more force to pull the threads in.

Thanks for everyone's comments. I hope this helps someone else:)
You forgot the most important part of the job. Put the tennis ball on that damn hood latch. Lol
 
TOO CLOSE HAVE YOUR SPACER TURNED DOWN OR REPLACE IT -i WAS GOING DOWN A BIG HILL HAD TO GET ON THE BREAKS HOLE IN RAD!!!!!!!!!!!!!!!!!!!!!!!!
 
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