Having trouble keeping the Bronco cool.
Wondering if I need to get a mechanical fan on it.
I just replaced the thermostat to make sure that is not the trouble.
Water pump is about 2 weeks old.
Old one worked fine but dripped from between the pump casting and the sheet metal backing plate.
Radiator is new.
Has an electric fan mounted on the front of the radiator.
Seems to move a good amount of air, but wondering if it is enough.
Former owner went with this set up because there is minimal clearance between water pump snout and pulley and the radiator.
Pics below showing set up and about an inch from radiator core to pump snout.
Wondering if I can squeeze in either a stock style fan blade or a "flex fan" type in the little space that is there.
Looks like about 4" between radiator core and the nearest belt.
Anyone face similar situations?
Know of a fan blade that might fit without eating the radiator and/or belts????
Appreciate it !!

 

Hi RSCHAP1!

Nice Bronco BTW!!!!!

There could be a couple of issues going on here IMHO.....

One of the greatest impactors that has come to be are the "high-flow" replacement water pumps that were introduced (and still here) in the late 70's......although 99% of it is a better impellor design, it did increase the flow rate of coolant in the system.....Now originally, the increased flow was 3% IIRR which still gave a good amount of time for the coolant to absorb the heat and expell it at the radiator but over the years & especially in the mid 80's the engineers upped the design again and well, that's when we all starting to see our engines running warmer (you also have to remember at the time these same style water pumps were still in use on the new vehicles- which were designed for the increased flow). On our Mustang the flow was so great that it would cause the radiator cap seal to "lift" under higher rpm causing fluid to expell, which we addressed with an overrflow/recovery tank (had to home-build that one at the time), which today is a common standard so to speak.

The increased flow/cooling issue is really nothing new though, as with the flatheads- had the same/similar problem caused in part by increased HP/TQ & speed- the solution was to install a giant washer (restrictor) at the upper radiator inlet- this slowed the flow to allow greater absorbsion/cooling.

Just an fyi- the V8's of the 70's (mid to late) because of design changes (smog related) were much more sensitive to ignition timing changes than the previous engines- in regards to more timing makes the engine run much hotter and possibly overheat- a couple of degrees advance is ok but any more and you could see temps spike up into the hot/boil-over zone.....I suspect it was from the oem lean-burn design.

Now for what IMHO the prime issues is...the E-Fan.....

In the aftermarket world 99% of the e-fans are junk in terms of design & quality IMHO. The OEM units flow anywhere from 50% to 200% more CFM than the "Hi Perf" aftermarket units, last for years in real world daily, all weather use and are quiet- and are less expensive in most cases!

I bought (3 years ago) a replacement assembly for my wife's 1997 Cougar Sport (V8) (the bearings in the e-motor were starting to whine).....the entire assembly including the shroud was $120 with tax (I bought the entire assembly because the motor itself was $80).

You will also hear/read about people having issues/concerns with their engines running warm/hot, once it is really verified and there are no mechanical issues, 99% it can be traced right to these HP Aftermarket fans.....those using oem units- I have never in 20 years heard of an issue related to them in any way in regards to cooling nor (seldom) have I experienced issue with mechanical fans (assuming they are functioning correctly)

In the classic Mustang world, there are many oem units that work well and sized to fit to choose from…..the V6 Ford Taurus fan (90-95 3.8L), If space is tight, the 95-00 V6 Ford Contour, 99-02 V6 Mercury Mystique, 99-02 V6 are flatter in design IIRR but if you don’t mind making your own shroud…..
Custom Electric Fan install - Taurus + Aluminum Shroud - Vintage Mustang Forums

 

Can't ask for more help and insight than that.
Appreciated !
Seems like I do recall the Taurus electric fans being a popular upgrade.
I had wondered about some of the things you mentioned.
Originally when I saw it getting hot, I pulled the stat and ran w/o to see if it was not functioning properly.
I did replace with a new one wondering if the constant flow wasn't giving the water time to cool in radiator.
It does seem better now with new stat in place.
Right now contemplating adding a mechanical fan to see if more airflow is what is needed (if I can even squeeze one in), or...
even though the radiator in there is new, replacing it with an aluminum one to see if that drops temps....
Really I need to drive it further than just around the block and see how hot it gets now too.

 

When I first rebuilt my Bronco I went with a serpentine belt system that didn't leave room for a fan between the water pump and the radiator, so I used two small electric fans in the upper right and lower left corners of the radiator. Cooling was always marginal with that, and eventually I went back to a stock V-belt system that left room for a stock mechanical fan. No more cooling problems.

That said, while a low flow aftermarket fan could certainly be your issue (as Beechkid noted), even a good fan will seem anemic without an effective shroud. If you don't have a good shroud you aren't using all of your radiator (I included a stock shroud with the stock fan when I went back to V-belts).

 

With regards to aluminum radiators......I know many seem to be under the impression (marketing) that aluminum construction by itself will enhance cooling, there is a little more to it than that...and in many instances buyers are actually comparing apples to oranges when comparing a copper core spec to an aluminum spec radiator. US Radiator has a nice vid on their site that yeah, it does talk about the company a bit, but also talks about Copper vs aluminum & gives a good presentation of design limitations. US Radiator has been around for 40+ years. The guy who presently owns it started working there 30 years ago and with the exception of 1 or 2 items, everything is built at their facility. They are also great to talk with on the phone and if you tell them exactly what you have, what are your concerns or wants, they will tell you exactly what to order. I don’t know of anyone (including the racing community) who has not been pleased with them!

Link: http://www.usradiator.com


US Radiator Corporation
4423 District Boulevard
Vernon, California
323-826-0965

Properly maintained, the oem systems are more than adequate, I'm betting the existing e-fan is the issue assuming the radiator is not clogged, etc.!

 

[QUOTE=Nothing Special;16440930]even a good fan will seem anemic without an effective shroud. If you don't have a good shroud you aren't using all of your radiatorQUOTE]

Agree!