Nurdyguy

I took my '65 in to a shop for some other issues (see '65 slugishness) and also asked them about some overheating issues I sometimes have. Most often it occurs in traffic, like if I decided to drive the Mustang to work that day and get stuck on the freeway. One day it was so bad I almost buried the needle on "Hot".

The mechanic said that the fan doesn't spin fast enough at idle (e.g. stuck in traffic) and recommended adding an electric fan to the front to help out. I've been researching and can only find electric fan replacement kits, nothing that adds a second fan. Did I just misunderstand him? Also, I saw a kit for a 6-blade replacement fan with clutch.

Anyone have experience with this? Anyone heard of a second fan addon? Opinions on 6-blade with clutch vs electric?

Thanks again!

Starfury

Couple questions, in order to facilitate more helpful answers:

1) What kind of fan do you have now? Is it a flex fan, or a solid fan? How many blades?

2) Do you have a fan shroud?

3) What kind of radiator do you have? Is it brass/copper or aluminum? How wide is it? 2-row or 3-row?

4) How do you know the engine is overheating? You can't go off the stock gauge. "H" is not a temperature. You need to get an actual temp reading, either with an accurate mechanical/electric gauge, or with a non-contact infrared thermometer.


An add-on pusher fan (mounted in front of the radiator) is a stopgap measure. Properly set up electric puller fans (that flow >2500CFM) are great...but are usually overkill, and are a bit of a PITA to install and wire. For most people, a fan shroud and a clutch-mounted fan properly spaced within the shroud are enough to keep the car cool. This setup works for me in 110F heat with a 3-row copper/brass radiator.

Nurdyguy

Thanks for the response Tad.

The car is almost completely stock so what it has is probably original. (It's still at the shop so I can't just pop over to the garage and look.) The fan is 4-blade unshrouded.

That last time this happened (overheating) I was on my way home from work, in August, in Texas (about 100 degrees with probably 35% humidity). As I mentioned before, the needle was buried on 'H' and at one point, while at a stop sign with my arm hanging out the drivers window, I could feel heat emanating from the under the hood. I know that's not exactly scientific, but that thing was HOT. The radiator did not boil over though. I'm used to cars holding the needle at about 1/3 of the way on a temp gauge so when I saw that thing burried I got concerned.

My parents mentioned a couple of years ago that they were having some overheating problems in the summer (summer in Palm Springs = 125 degrees) and they did something but I don't know what. (My grandmother was the original owner of the car and it has passed down the family chain.)

Starfury

Is there an overflow tank? If not, consider adding one.

Step one would be to pick up a clutch fan setup (both the fan and the clutch) and a radiator shroud. Clutch fans work very well, and are still used in modern vehicles. They're also much quieter and more simple to install than a proper electric fan system. The fan should be spaced about half in, half out of the shroud for proper airflow. Spacers are readily available from most parts stores.

Step two is to either rig up an accurate mechanical temp gauge, or get yourself an inexpensive infrared thermometer to verify readings from the stock gauge.

If the fan/shroud option doesn't do the trick, you may need to look at a new radiator. A 3-row brass unit, or a good 2-row aluminum, would be fine. I believe the stock radiators were 2-row, but you'd have to pop the cap off and look inside to see what you have.

Boogie's_AutoRama

Verifying that is indeed running hot by using an infrared thermometer or installing a dial gauge is a good idea.

If it is running hot, my advice is to ditch the water pump mounted fan altogether and install a 16" electric fan like this.

http://www.ebay.com/itm/16-Reversable-12V-Radiator-Electric-Thermo-Fan-/201259586240?pt=Motors_Car_Truck_Parts_Accessories&hash=item2edc0192c0&vxp=mtr
It can run full time if your alternator can keep up (65A or bigger). Or hook it up to a thermo switch.
Either way, definitely wire it up with a 30A relay.
All simple stuff for any mechanic with even moderate skills.

If you want to fix it once and for all, get the elec fan and a new radiator.

http://www.ebay.com/itm/TRI-CORE-FULL-ALUMINUM-RACE-3-ROW-COOLING-RADIATOR-64-66-FORD-MUSTANG-V8-I6-MT-/381150040522?pt=Motors_Car_Truck_Parts_Accessories&fits=Year%3A1965%7CModel%3AMustang&hash=item58be5011ca&vxp=mtr
Chose what ever vendors you feel comfortable with, the above links are just examples.

Unless your intent is to keep it original don't feel like you need to keep adding band-aids to the old technology these cars were equipped with.
With modern parts like alum radiators and elec fans you can bring this thing into the 90's.

WestCoastShelby

First inexpensive step is adding a shroud. They can bring down overheating temperature by about 15 degrees without any other changes. Get the concours reproduction shroud and brackets to match your core depth.

Starfury

^That fan does not flow nearly enough to replace an engine-mounted fan on these cars. I'd call the 2100CFM it advertises optimistic at best. A fan from a Mk VII or a dual-fan assembly from a Taurus are the best options (each flow >3000CFM) shy of an expensive aftermarket fan/shroud combo.

Wiring fans like these, while not rocket science, is more complicated than simply replacing your fan and adding a shroud. It's also more expensive. Between the two, I don't recommend it for many applications. It's got great 'wow' factor, but it's just not necessary for most cars.

Also, ^that radiator is exactly what I'd recommend against. It's a cheap gimmick radiator. http://www.ebay.com/itm/NEW-Aluminum-Radiator-1964-1965-1966-Ford-Mustang-289-V8-NO-3-ROW-GIMMICKS-/391046157824?pt=Motors_Car_Truck_Parts_Accessories&fits=Model%3AMustang&hash=item5b0c2ad600 is what I'd recommend, if you want to go aluminum.

WestCoastShelby

Why go electric when you can get a 6-blade fixed fan for $40?

Starfury

While fixed fans work, I much prefer clutch fans. They're much quieter most of the time, rob less power, and I think you can get a clutch and fan for ~$80.

barnett468

ok,

a clutch fan actually never spins at the speed of the pulley . . yes i know it sounds weird but it is true . . a heavy duty fan clutch spins faster than a std fan clutch . . the reason a fixed fan is noisier than a clutch fan clutch is because it always spins faster which of course moves more air which of course is the goal.

your overheating prob sounds fairly big . . if in fact it does run hot, i would not mess areound or take chances and would do the following.

buy a 1717p flex a lite fixed blade fan from summit.

buy the shroud . . drake has an aftermarket shroud that works better than the orig but might look hokey.

run 30% antifreeze and 60% water.

buy a 192 thermostat.

use a 13 lb rad cap.

if it still runs hot then buy the rad suggested from us radiator . . coolcraft.com sells them . . do not buy one anyewhere else because it will be a tiny tube chinese one.

.