Electric cooling fans

I have a 68 X code (4 bbl, .040 over) with A/C that runs hot, hot, hot. It is especially bad on warm days and is worse when idling.

I am looking at cooling fans and WCC has a 24 inch (2550 cfm) setup. It is a direct fit, but I am wondering if it is sufficient for my application.

Thanks in advance for your help

Ken Jones

That doesn’t hold a candle to the stock fan. Most likely you have a radiator issue.

Thanks for the reply Bill. The radiator was re-cored about 5 years ago and made no difference in operating temp.

When I purchased the car, it was missing the fan shroud - I added that, hoping that would help but that didn’t seem to either.

Can you post a picture of your fan/shroud?

Do you have a stock water pump or aftermarket?

I will post a picture when we get back from vacation. It is a stock water pump. When the car is moving, it is typically ok. It is when it is idling in traffic that things get dicey.

Lets see which fan and shroud you have. It may also be a bad fan clutch. The next time it is hot, stop the engine and then see if the fan is difficult to turn. If it moves easily then the clutch is bad, it should slip when cold and almost completely lock up when hot.

I don’t think it is enough airflow.

I like electric fans though they seem to have a bad reputation here. In my experience with a mild 351C (unknown specs, built by previous owner), a single 16", 2800 cfm electric fan was insufficient to keep the engine cool during extended idling and low speed driving conditions with ambient temps in the mid-80s. Driving at even surface street speeds kept temps under control so I knew I had sufficient radiator heat rejection capacity (new radiator) and water flow (new hoses, heater core, Flowkooler water pump and correct Cleveland t-stat and diverter plate). This spring I installed 3450cfm electric fan (dual 11") and now I can easily control temp at 95F ambient and with the car stationary.

I’m not sure the repro fan clutches are quite “aggressive” enough as far as locking up when hot. I’ve got a new water pump, thermostat, hoses, 24" ACP MaxCore aluminum radiatior, fan shroud using a 7-blade fan with a new clutch. It still gets hot occasionally in stop & go driving.

The fan still seems to turn pretty freely on a hot engine, and I never hear the characteristic whoosh sound of the mechanical fan while revving the engine. Maybe I just got a faulty clutch, but at this point I’m planning the switch to electric fans.

It is really easy to check the fan clutch. When the engine is hot, the hotter the better, simply shut the engine off and see if you can easily move the fan. If so then the clutch is bad or it is spaced too far away from the radiator. There are two types of fan clutch, Thermostatic and Slip Clutch. The Thermostatic version is what came on the car and the slip type is the low cost replacement. The slip versions seem to get less and less effective the longer you run them. A stock 24" cooling system was adequate for the 428 Cobra Jet and the 427 side oiler.

Electric fans aren’t bad you just need to run ones that are at least as capable as the stock fan and most simply are not capable of moving that much air. Read what wawazat posted and get fans of at least that capability and also the high output alternator to match.

Hayden 2710

$25.89 from Rock Auto

Have you considered the Ford Contour fans? I had to fab up some mounting brackets to attach it it my radiator, but nothing complicated. They fit a 24”radiator in our cars like they were meant to be there…coupled with a flex a lite variable speed fan controller I have my temps locked down.

Summer in Florida 95 degrees with 95% humidity and the car doesn’t care if I’m idling along in traffic with or without the ac on.

I got the Flex-a-Lite 420. Works fantastic. Temp doesn’t budge even in 104 degree Houston stop and go traffic.

I’m posting an image.

There is a fan spacer, not a clutch. It has a flex-a-lite fan.

The water pump is stock.

The engine has been rebuilt. Bored .040, RV cam.

Okay this is really helpful. The fan appears to be too small for the shroud. You car came with the “Power Booster” fan, clutch and shroud system. It included a pretty aggressive 7 blade fan. It was mounted on a viscous thermal clutch that allowed for the more aggressive pitch, that really moved a lot of air at low speeds, and then slipped at higher engine speeds to reduce drag and avoid over speeding the fan blade. Apparently some previous owner pulled the good parts and probably though they were going to get more HP with this set up. If you can find a deal on an alternator and maybe the fan and shroud off a Taurus that will probably cost less than the right fan blade and clutch ($300?)

Had this on hand so thought I’d add some more visual interest to this thread.

I collect vintage auto related logos.

It is a 6 blade plastic flex-a-lite fan.

There is about a 1 inch gap between the shroud opening and the fan blade.

The 390-2V X code engines ran very cool with the stock setup even here in Texas at over 100 degrees temperature outside with the AC blowing. The stock components are identical to what was used on the 427 and 428CJ. Those engines also run cool in any kind of weather.

The fan that you have is no doubt inferior to the stock unit. But it might be something simpler like the distributor advance is not set properly, or maybe the timing is retarded in an effort to use cheap regular gas, or the vacuum advance is not hooked up, or the centrifugal advance is stuck. I would check all of those things before buying anything.

Thanks for your input Royce. Actually, I appreciate everyone for chiming in.

It is using a Road Demon 625 with vacuum secondaries. An MSD ignition with MSD distributor.

I’m not sure of the current timing - been a while since I set it.

I’ve posted before on other Cougar boards in the past. I bought this Saxony Yellow XR-7 in 2002. It spent quite a while disassembled as I replaced the heater core. Back problems kept me from working on it until 2 years ago. It’s been running well since I put it back together, but has the cooling issue that plagued it since I bought it.

Ken J.
68 KAT

An aside: the P.O. had a Holley 750 with mechanical secondaries. It ran horribly.

I just had the C6 rebuilt with a Wide Ratio kit added.

The distributor timing is critical to engine performance. You need to know it. Otherwise everything else that you do is wasted.