Big 500 cubic inch Caddy engine fan vs stock Chevy fan vs electric fan

[Mike Phillips]

Big 500 cubic inch Caddy engine fan vs stock Chevy fan vs electric fan


Talked to one of the guys at the local radiator shop that recently re-cored the radiator for my BMW Truck, which you can see below parked next to a dark gray BMW, (Looks like a Datsun truck but look at the hood carefully).




Anyway, they did a good job and seem to be quite knowledgeableabout their craft.  So I tell the guy I'm putting a big block Chevy in my old Jimmy and start talking about cooling option and he tells me that the fan that came on any of the 1970's era Cadillacs that came with the 500 Cubic Inch engines was designed to pull some gargantuan amount of air through the radiator and keep that big engine cool.  He said it should bolt up to my Chevy water pump.

Anyone ever hear of anything like this before?

Curious about his comments, while I was out in the local wrecking yard I spied a 1975 Cadillac with an intact 500 cubic inch engine including the fan, fan clutch, and shroud.  The wrecking yard wants about $30.00 bucks for those items.

Here's a picture taken with my iphone,




This radiator guy was pretty adamant that this fan system would pull more than enough air through the radiator to keep the engine cool.


Any comments?

[SUX2BU99]

That's probably not a bad idea and he's probably accurate that the OEM setup pulls a lot of air. Downside is it's just that much more drag on your BBC, and robbing more horses.

[exilous]

Your right it does look like a datsun, what year is it? I dont think that it would be a problem with the fan it can't rob too much horsepower. And if your going to be building it to make some big horsepower I wouldnt even worry about that factor.

[HAULIN IT]

Mike, Tell us more about the Datsun, Luv...er BMW truck. Goes to show these guys were all allot more in cahoots even back then, I've never seen/heard of one. Really just a BMW engine I'm guessing? Diesel? What does the fender emblem say, How about the gate?
 As far as the fan goes, this has been a joke of mind for years. I've been saying the "fan maker guy" at GM had it figured out by about 1973 what the best fan was in terms of cooling/drag, ect. & still had to go another 20 or so years to collect a pension, sooooooooooo. The 5 blade, the 5 blade with one farther apart, the much more curved 5 blade, the 6 blade, the 6 blade curved, TESTING, TESTING, the 6 blade with the wide space, the 6 folded blade, the 7 folded blade, the 7 curved blade, the 7 curved blade with the wide space, MORE TESTING, back to the 4 blade, STILL MORE TESTING, oh don't forget the 3 blade on the S-10's, ect. Now the guy is just about to retire.
 Really all of the big, clutch fan blades will work well with a good rad & proper shroud. I'm not sure about the clutch bolting on to your BBC, some of the B-O-P-C water pumps had a wider bolt spacing than Chevy, at this moment (besides Olds did) I can't tell you which ones, so you may have to get a different clutch.
 I used a '80's 6 blade 425 Caddy radiator, fan & shroud when I did a 502 swap in a '84 Caprice for a guy. No problems at all, even with the A/C on. It will do the job for you. Lorne

[Mike Phillips]

Mike, Tell us more about the Datsun, Luv...er BMW truck. Goes to show these guys were all allot more in cahoots even back then, I've never seen/heard of one. Really just a BMW engine I'm guessing? Diesel? What does the fender emblem say,

I apologize for my bad attempt at humor.  It's a 1974 Datsun truck and I glued a BMW emblem on the hood.





Had to add my own cup holder,






 

[VileZambonie]

I thought that was pretty obvious.

I would stay away from that old fan as the clutch is probably shot or most likely going to be. The blades may crack due to age and rust especially once it starts wizzing along again after being at rest for how many years?

The BBC cooling system is plenty adequate for your truck. If you want additional cooling add a pusher fan behind the grill.

[Mike Phillips]

I would stay away from that old fan as the clutch is probably shot or most likely going to be. The blades may crack due to age and rust especially once it starts wizzing along again after being at rest for how many years?

The BBC cooling system is plenty adequate for your truck. If you want additional cooling add a pusher fan behind the grill.

Too late...






Seems to fit right onto the Chevy water pump.



NAPA said they couldn't get me a new clutch so just for fun I'll check with the one of the classic Cadillac forum.  I've owned 5 - 1959 Cadillacs, 2- 1960 Cadillacs and even a 1949 Cadillac and it was always amazing what could be had for these old cars.

Checked out the radiator on this 1975 Cadillac Coupe deVille also and it's in physical good shape on the outside, don't know how to tell if it's any good on the inside.  It's 4" wider than my stock radiator, a 1/2" thicker but the same hight.


 

[Mike Phillips]

Autozone has a fan clutch in stock for $60.00

 

[VileZambonie]

Check it very carefully for cracks. I had a fan blade break off once. I was under the hood tuning it and revving the engine moments before it happened too. It surely would have messed me up. After I closed the hood and went to do a burn out the fan blade went through the shroud, through both layers of the steel hood and landed in the middle of main street. It traveled about 175 feet when it came to rest. So be very thorough on your inspection of that old fan especially around the rivets.

[roadrage41]

that thing needs some 14 inch meshies like no other.

[HAULIN IT]

Vile, Was this an OEM fan blade?

[VileZambonie]

In that case no it wasn't however I have had quite a few broken fans come through. My friend has all of his broken parts hanging around his garage and has quite a few fan blades on the wall.

[SUX2BU99]

Was that an infamous Flex-a-lite blade breakage? I've heard of that enough times over the years to not want one. Hmmmm, now that I think about it though, the fan on my truck kinda looks like one of those. 

Has anybody actually heard their fan clutch activate? I swear I've never heard mine come on, and I expect that loud roar sound like you hear some OEM setups do when they are cold. I once heard the one in my 99 Dakota R/T come on in hot traffic but other than that, it too never seemed to activate. Perhaps the 'freewheel' spin those things do is enough most of the time?

[andreajones021]

That's allegedly not a bad absorption and he's allegedly accurate that the OEM authority pulls a lot of air. Downside is it's just that abounding added acrimony on your BBC, and addition added horses.


_________________
Bathroom fan

[Mike Phillips]

That's allegedly not a bad absorption and he's allegedly accurate that the OEM authority pulls a lot of air. Downside is it's just that abounding added acrimony on your BBC, and addition added horses.

I'm guessing this was a comment about the Cadillac fan in my Jimmy?

If so, I've been driving the Jimmy for going on 2 weeks now and everything's running great!

Since this isn't a race car I don't care if wastes a few horsepower, at least for now, one thing for sure, when you floor the throttle the truck first jumps and the takes off like a bat out of heck.  She's really fast!

The engine never goes over 180 degrees either.  I just had a Bikini Top made for her about a week ago and it looks great and keeps my seat dry here in Stuart, Florida, my new home.

Heres' a couple of recent pictures...