First, welcome to the forum.  I post here about my '67 fastback, but I enjoy all manner of vehicles.  My Dad and uncle had a bunch of Vettes growing up.  The baddest of which was my uncle's '67 L88. 

Second, why do you think you should replace an electric fan with a mechanical one?  Consider that all new cars have electric fans.  If the car has an electric fan and it isn't cooling properly there are a litany of reasons as to why that have nothing to do with the fan.  Also, all electric fans are not created equal.  Cheap fans don't move enough air to properly cool, and the motors aren't sealed so they don't last.  A good fan uses 10 amps per 1,000 cfm air moved.  If the fan has say a 20 amp fuse you know its moving 2,000 cfm or less.  You will see fans advertised all the time claiming they move 3,000 cfm and draw 20 amps.  That's because the fans were not tested with a radiator in front of them.  In open air the ability of the fan to move air is significantly increased, and totally bogus, unless your car has no radiator.  My research led me to go with a SPAL fan (30102082).  I also built my own fan controller using two relays.  I've driven my car in 100+ degree heat and the engine ran at hottest 205 degrees.  I have a 3 row copper/brass radiator, stock water pump, and a 180 degree t-stat.  With the mechanical fan, even shrouded, the car would have overheated under those conditions.

Third, I would not run a t-stat of less than 180 degrees.  If everything else is right you should have no problem keeping the car cool with a 180.  The lower the operating temperature of the engine the greater the engine wear.  This relationship is not linear; its exponential, so the difference between a 160 and a 180 is not as insignificant as it would seem; its along the order of a 30% increase in cylinder wall wear.  New vehicles run t-stats in the 195 degree range, which is part of why newer engines seem to last so much longer than older ones. 

Fourth, with the engine in your car an unknown its hard to know what the PO did.  The potential problem you have is that there are two water pump configurations for SBF (two rotation directions anyway let's not inundate the guy with the minutia of length, etc.).  Each has its own timing cover with the water inlet passages clocked accordingly.  The 5.0 used a reverse rotation pump designed for a serpentine belt.  The older cars used a standard rotation pump with v-belts.  Swapping a 5.0 to v-belts iasn't as simple as just changing the water pump and accessory drive.  If you fail to change the timing cover you'll likely get overheating,. especially in a high performance application. 

Finally, there's no magic cure to overheating.  Throwing money art the problem will lighten your wallet, but likely solve nothing.  Keeping these cars cools isn't rocket science; its the right combination of parts working together.  The first thing to do to correct it is to figure out what's not right or not working in the current setup. 

Good Look'n wrote:

Why is the "89 or 90 Crown Vic, Town Car or Merc Marq" better than a Mustang unit? Larger?...moves more air?

Why...because it's Ford OEM and it has likely proven itself to be reliable.  And, it's the right size (17") and it's the proper rotation (CW) and it's not 60 years old (only thirty)...though I'm running the seven blade that I think came on our 66 with factory (not dealer installed) AC.  I do still have the six blade that came off of the Lincoln TC donor car where my core engine/trans, EFI, etc. came from on the shelf.  After the Falcon experience I will be pulling that old fan for an inspection before the Bash trip this year.

Good luck, hope you make a bash trip one day if not this year.

BB

Bullet Bob wrote:

.........snip........
Also:  Get that beauty reliable and follow RPM this way when he comes here to hook up with us  on the way to the Bash in Michigan mid June.   You'll be glad you did.

Good luck, beautiful car.
BB

Just checked the trip out. Damn, it really looks like fun but at a 5k mile round trip, it's more than time permits this year. Going w/ RPM would be cool but I'll keep it in mind for next year (if this is a yearly event).

Speaking of cool...once this overheating prob goes away, I'm installing a vintage A/C system...at this stage in my life, the only time I'm willing to sweat is when I'm making all my many 20yr old girlfriends happy

 

Alessandro wrote:

Hello Good Lookin ........snip......

Bet you say that to all the guys.......(been waiting for someone to say that).

Ya, definitely have to lick the heat prob before considering A/C. Seems the new rad did the trick for you.

What have others done about lowering or removing the stay-up radio antenna? Never play audio in a car & the antenna screws up my car cover. I replaced the powered adjustable one in the vette (it stays up a foot or so) w/ a new top part (w/ the ball) that falls into the bottom chrome mount. Thinking of doing the same on the Mustang. If you look at the interior pics, I'm replacing the front  rear lick panels w/ stock ones...those huge black speakers have got to go
 

Welcome good look'n to the best Mustang forum on the net!
When I had my Mustang painted I COULD NOT being myself to bore-a-hole in my fender!!
I just got one of those rubber ones and laid it on top of the heater box under the dash.....Not that I could hear a radio anyway (long story!) I just play my bluetooth on those long bash road trips.
I installed the Shelby front apron on my 66 and that was the end of the over heating problems. I think that's why "old Shel' designed it...for heating issues.
Not sure how it would work out with an AC condensor in front.
Besides.......I thought(here comes) ALL you Southern Cal fellas were sooooo cool you don't need no stink'in AC!! Besides....it ain't the heat.......its the humidity (which I thought y'all didn't have!!
Ron Howard  and the Fonz and all those SC guyz were plenty cool in the flix soooooo naturally I thought EVERYBODY out there was the same!!!!  J/K
6sally6

Good Look'n wrote:

Thanks to both of you & the welcome...you bring up good points.

Bullet Bob>
Glad you liked the story. It was a fun trip, even w/ the overheating (I got lucky that it didn't happen in the vast wasteland).

I was going to install the larger rad at first (did read MS's article). Since the Vette's overheating was cured, I decided to do the same things here. If it doesn't, I'll see if anyone wants a very slightly used Dewitt rad!

Why is the "89 or 90 Crown Vic, Town Car or Merc Marq" better than a Mustang unit? Larger?...moves more air?

Read that post...ouch!...I'll try to get a proper steel oem...sure as hell will stay away from Derale.

I'll look into that trip....I don't show my oldies, I drive 'em! Longest trip so far was the coastal route (1k miles) to No.Calif. in the vette...lot's of fun.

TKO>
"my uncle's '67 L88".....OMG....OMG....OMG!!!
If that had stayed in your family, it sure would increase a relative's net worth, eh?

I've read lot's of discussions about the electric vs. mechanical fan debate. There's merit to both sides. For now, I'm going the mechanical route.

If you check out my trip article, I drove through LV w/ the car after buying it. I wouldn't have made it past the town if it was summer.

You're right about the thermostat...lot's of folks think it'll help w/ overheating & it's the first thing they try (to no avail)

Afraid you lost me on your comments about the timing cover. Would it help if you saw my engine setup? If you go to the Bring a trailer link, it points to the auction with professional video & pics the seller made.

Unfortunately the two timing covers look identical from the outside.  You would need to pull the water pump to see the coolant passages. 

The L88 remains the most frightening car I've ever ridden in.  I don't know what the factory rating on them was, but in reality they made about 650HP.  That car had the close ratio M22 and a 4.10 rear gear as well.  Only 2nd and 4th were really used in normal driving.  The right pedal was really a tire spin pedal, not an accelerator.  My cousin once downshifted into 2nd at 40MPH and floored it and the car did a 180 in the middle of the road.  On slicks at the Vette Nationals it ran mid 10s in the 1/4 with the guy my uncle got it from driving.  He was a prominent guy in the Corvette world, and a great guy all round.  Sadly he and the L88 are both long gone, leaving me only fond memories of both. 

The cars were valuable back then, but nothing like today.  My Dad had a '69 SS396 ElCamino, a '69 SS396 Chevelle, and a '72 Vette with a 454 (not at the same time).  My uncle also had a '66 Chevelle SS396 convertible and every option that could be had in '66 except a power driver's seat (PS, PB, PW, PL, PT, AC, Tic-Tock-Tach, etc.).  That car I do know where it is, and the owner knows that when he's ready its already sold all he needs to do is call me and state the price.  I was old enough to drive that one. 

I've gotta agree Mike. I once put a 440/727 into an A body station wagon .... left the slant six rear axle in it.
Tyres were definitely the fuse. First car I ever drove that you couldn't floor it from a light if you expected it to move forward.

Welcome to the site. There is a great group of Folks here. Great story for the drive back, sounds like you could have been cooking in the car!!

With all the body colored paint under the hood, I can understand why you don’t want to cut the hole for a bigger radiator. Hard to touch that up with a rattle can!!

Not all electric fans are created equal. Spal  brand seems to get the higher approval ratings. Opening the scoop should help some. Forced air while moving and a heat escape when you aren't.

Hayden 2710 and 2711 are popular choices for normal rotation fan clutches. The difference is the fan mounting height. There is a thread on this site somewhere that covers them. One has a different bolt spacing for the fan. Derale fans can come with both bolt patterns, but have lost popularity after several have turned into projectiles!!!
 
I agree that you really need to verify that the parts you have should work together for rotation. Also, how is the timing and carb adjustments? Improper setting can cause over heating issues.
 

Finally!...starting the long delayed Cooling The Hot Horse Project. Told each of my GFs (all of whom are above the age of consent to their mid 20s) to keep their hands off me until I'm finished or get frustrated & sub the work out....whichever comes first.

The PP (Poor Pony) has been resting in the garage for almost 2 yrs since purchase. If you look at the sign I made in the below pic, you'll understand me better. BTW...the print above it is by a famous artist, a True Legend in his own mind.

 
Showing pics via an outside site is a pain...just say'n...

Received the Dewitt rad today....kinda pricey (5 C-notes, on sale). I learned of them when the '66 vette had the same project done. The Corvette Forum folks thought highly of the brand (they design/manufacture these in-house) & my experience with the vette's rad has been excellent. Besides, I consider that I got it free since the seller sent me that amount after reading the article on the drive home from Utah to Calif. See my BaT article for details.  
  
 
  

Question of the hour ...anyone have info on this Adjustable Aluminum Fan Shroud? >>    https://www.summitracing.com/parts/sum-380461-sh 

I prefer not to use a plastic shroud, but I worry this would have a one size fits all look. If anyone has seen it in person, I'd value your opinion. Seems a decent enough price as opposed to having one custom built. 

Question of the 2nd hour.......just noticed that I have no fan clutch...yea... kinda slow. Obviously, the electric fan doesn't need it (full disclosure, this is my 1st experience w/ those electric thingies). I guess this means that I have to trash that nice pulley, eh? Do I even have room for the clutch & new pulley?  


 

I'm looking at your pix and I believe there is a major problem.  I don't know how anyone could expect to do ANYTHING on a car in a shop that is that clean.  Maybe that works okay on Vetts but, man, you gotta mung it up a bit if you 'spect to work on a Ford.

Like the road-duster pic though...except it's got a Bowtie motor in it.  But then, most of them do.

BB

Welcme to the forum. I believe old cars that came with mechanical fans should HAVE mechanical fans.  Just because I like them that way.  They can certainly do the job without adding a bunch of wires and sensors.  If one wants electric, so be it, but a mechanical fan can certainly do the job. And Ford made some great fan shrouds for 67-73 Mustangs. The 65-66 fan shrouds are pretty worthless.  You can bolt in a 1967 20” radiator with no cuttng, and the factory 20” shrouds work great. My 427 stroker uses a 17” six blade flex fan.  Never any heating issues.

In my experience from running this forum since 2000, most overheating issues are related to water flow, whether in a fifty year old block that is rusted internally or a plugged up radiator, or thermostat. And nobody ever talks about their timing or the performance of a vacuum advance on their distributor. An improperly functioning advance can cause low speed overheating.  I have also seen cars where the temperature sending units were installed where they did not reach the fluid level in the manifold. Installing them properly made the “ overheating” problem immediately go away.  A radiator that has been overfilled andcthen pukes water on the grround is also NOT indicative of an overheating problem.  It is a sign of an overfilled radiator. I do not run an overflow bottle and my car does not puke water. The fill line is 1” below the filler neck of the radiator. Any extra fill and WILL puke until it reaches the correct level.

Good Look'n wrote:

MS...stop rushing me....geezz, you're like one of my ex-wives...forget which one.

 
That's hilarious!