The other day it was kind of hot outside and I got stuck idling in traffic for a long time. Water temp got up there - I only have the stock '66 gauge and it was at the right side of the P vs. straight down the middle normally. It did cool right down once I was back on the freeway. The coolant is 2 years old so I'm going to change that and the thermostat. But I've also starting reading about the various fan set ups people use. I see that some folks use a 7-blade Granada fan, and some use other fans with a clutch. If I go with a clutch fan set-up, I'd want it to be a Ford set up so it looks somewhat like it belongs there, i.e. no Flexlite or electric fans. I have a standard 5-blade fan with the 2-1/4" deep shroud which is about 18" wide.
A clutch fan set up sounds like it would cool better at idle and be quieter at higher RPM's. So I kinda like that idea but don't know which fan, which clutch to use. Does anyone have specific Ford part numbers they could recommend that would fit that shroud? Would I need a different fan spacer? With the 5-blade fan there's about 3/4" to 1" of clearance with the radiator now.
With the fan clutch you need the clutch AND the matching fan, which has a larger center hole and bolts to the clutch unit. IIRC, the correct clutch is the Hayden 2717 and the typical fan a Flex-a-lite 6717... but don't quote me just yet.
While the clutch fan will help with parasitic loss and noise at higher rpms, I'm not sure it will help with your "stopped in traffic" heating issue. The most common cause of heating when stopped is lack of adequate spark advance. Newer fuels burn slower and if you've installed an aftermarket carb the chances are it's a bit lean, too. That also makes it burn slower so excess heat ends up in the exhaust port instead of being turned into mechanical motion and the coolant has to take up the slack. Consider running as much timing at idle as the motor will tolerate, including switching your vacuum advance signal to full manifold vacuum. If you have air conditioning, note that Ford equipped factory A/C models with a 3-core radiator with an 11 fin per inch count, and a Hot Idle Compensator mounted in the Autolite carburetor. This unit is controlled by a bi-metal spring and would open a "controlled vacuum leak" to raise the idle speed slightly to move more air and coolant. If you no longer have one, you might want to consider adding a 12v throttle "kicker" solenoid, triggered by the A/C compressor clutch, to raise the idle when the A/C is cycling.
I'm using a Hayden 2710 and a fan off a GM truck I had lying around. The key is to make sure you get a fan that fits in the shroud and as others have noted, it needs to be about half in. Hayden has nice dimensional drawings on their catalog, so you can see where everything will fall. If you need to adjust the position, you can do as huskinhano did inhis pic and put a spacer behind the clutch flange.
With the fan clutch you need the clutch AND the matching fan, which has a larger center hole and bolts to the clutch unit. IIRC, the correct clutch is the Hayden 2717 and the typical fan a Flex-a-lite 6717... but don't quote me just yet.
Hayden shows 2717 as a reverse rotation clutch. I think your fan recommendation is spot on though. Another option would be a unit from Derale, they make them in 17" through 20".
Should work. I'm using a late 60's/early 70's GM 18" fan with a 75 Impala thermostatic clutch. I bought the fan off CL. I have the fan clutch with in a 1/2" of the radiator. The fan blades are less then ideal 1.5" or so from the core and no fan shroud, which it really should. The bottom line it cools great. Even idling it's fine. It's also very quiet
Be sure to choose a clutch with a thermostatic spring. And a shroud will improve the efficiency of your fan. The fan should be half in, and half out, of the shroud's depth.
I have one car with and one without AC, and another AC car that is disassembled but all three have the original 7-blade C6OE - G fan and thermostatic clutch. The running ones are used with a shroud on a 3 row brass radiator, a 180 degree thermostat and 60% silicate-free coolant, full manifold vacuum and 36 degrees total timing.
No need to over complicate this. My stock 289, stock radiator, with a fan and clutch setup from NPD.
It keeps my car cool no matter what the temp is, sitting in traffic, whatever.
Just for the record, I didn't pay any of those "record" prices for the C6OE-G fans and clutches. It's all in knowing what you're looking for and when to get the good deal.
Unfortunately I didn't write down the part number and this receipt seems to have gone missing, but I have an Imperial fan clutch that was equivalent to the Hayden 2710.
I got the stock 7-blade Ford fan off of eBay for 25 bucks before someone decided they were made of gold!
On my 67 EFI conversion, I used a flex-a-lite 5917 CCW clutch type 6-blade fan and the matching fan clutch from a foxbody. I am sure they make a standard rotation fan, just don't recall the p/n.
Note that on the NPD website that the 6 blade fan is not warranted for use over 4000 rpm. They are absolutely correct. I replaced the original 4 blade fan on my car with the clutch fan setup earlier this summer and it only lasted until the next autocross where I developed a high rpm vibration and it made quick work of destroying my water pump. Not for high rpm applications! I went back to the original 4 blade fan.
I wonder if the 6 blade fan could be balanced for my 6400 rpm redline?
Funny you should mention that! I chased a vibration in my engine that would come in around 2000 RPM and it turned out to be a bent blade on my 6 blade fan. I straightened it out by hand and the vibration went away. I didnt discover the problem until I started removing belts.
IIRC the fan clutch is designed to freewheel above 4000 rpm so the question of the fan blades being over revved should not be an issue. Does anyone know differently?
I don't know, but I'd hope so, considering the harmonic balancer pulley is larger than the water pump pulley, resulting in the fan blade spinning faster than the engine rpm. I'd have to measure to do the math, but I can imagine it would be very easy to get a 289 to the right speed to cause the fan to surpass 4000 rpm.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Vintage Mustang Forums
4M posts
89.2K members
Since 2001
A forum community dedicated to vintage Ford Mustang owners and enthusiasts. Come join the discussion about restoration, modifications, NOS parts, troubleshooting, VIN codes, and more!