had a similar experience with 65 Mustang 289 all rebuilt with new Champion 3 row radiator. Ran fine down the road but in town would heat stoplight to stoplight. Tried high volume water pump, five blade fan a shroud, made it better but still a problem. Finally pulled my head out of my **** and tested the radiator cap. It let go at 5 lbs. New radiator cap 13 lb, end of problems. check that cap before you waste any more time or money.
I vote stock fan off of a a/c car (a/c usually have a bigger diameter fan) and as also stated get the fan blades out of the shroud... ...
Those plastic flex fans are ****. The blades don't flatten out they twist at the root and cause m***ive drag. It's probably why they explode. I'll concur that the fan appears to be over shrouded. A Windsor in the early Falcons was tight as it is. The more horsepower, the more heat. Quick trick would be to wedge the back of the hood open with spacers. See if the temp gauge stays steady at slow speeds. If so, it's a low speed air flow issue. Hot air can't get out and the engine bay is heat soaking. Is there an air dam under the rad support? This would promote a low pressure are behind the rad and under the car to help pull hot air down and out from the engine bay.
The problem with this setup is I can't really put a bigger fan in or move it back because it will hit the accessory drive and A/C compressor. I am going to change the fan but, I need to figure out how to fit it as well as check base timing. I appreciate everyones help. Hopefully I will have some answers this weekend.
Having the radiator encapsulated in a unducted box kills it's cooling capacity. Add some of those one way flapper doors to allow airflow. Those dead spots are just going to be hotspots.
It's starting to look like 3 lbs in a 5 lb bag... I've owned multiple V8 '64-65 Falcon/Comets in the past and never had any issues with overheating, but I didn't try to stuff AC on mine either. The engine compartment on these is just big enough. Three things I'd look very hard at, as I don't think it's any one thing. 1. The radiator. Yours looks small and is a 'special' as the OEM ones had both inlets on the p***enger side. Ford moved the lower one to the drivers side in '66. Typical core sizes were about 17" tall by 18-20" wide. If yours is smaller, that could certainly be a contributing factor. 2. The water pump pulley. Again, that looks small. A lot of those kits use a smaller pump pulley for HP gain, but for slow speed use don't turn the pump fast enough. Would a 'high flow' pump fix this? Hard to say... 3. The fan/shroud. As-is, it's ineffective and may even be impeding air flow through the radiator. Removing the spacer would be the fix, but the serpentine belt system is in the way. The cheap way out would be to hack the radiator bulkhead and move the radiator forward enough to get the right relationship between them, but you'd need to fab an offset brace to restore strength to the bulkhead. Otherwise, I'd say the serpentine belts would have to go, replaced with a V-belt system. Or switch to a single serpentine belt system, but that will require a different timing cover and water pump, plus new brackets. And oh yeah, ditch the flex fan. Use a five-blade steel fan instead (don't forget rotation...). Good luck...
You will say “ he is nuts” ! You need a distributor with a vacuum advance to better control ignition advance on a street driven car . It will advance the timing and engine will run cooler . Will it fix your problem ? Don’t know but what I can to try explain to you is : if engineers at FMC did not think it was needed how many millions could have been saved through the years of production by not installing one on every new car ?
Some rubber flaps on that shroud would be a big help. That would allow more airflow, especially where the fins are now covered. Many OEM plastic shrouds have these flaps to allow an easier path for airflow when at speed. Keeps the fans from having to cycle as often, if at all on cool enough days.
You could try a thinner spacer to put the fan blades half in/half out of the shroud, as they are supposed to be, however, the fan itself is a bit undersized, as well, being a really bad design that doesn't pull a lot at idle, that's for sure. Also, check your timing to see if chain stretch is present and killing timing at idle. just pop the distributor cap and rock the crank back and forth, looking for any lag. Car would still run ok but missing a bunch of timing at idle puts heat in the ports/heads/coolant. -rick
I f the engine is running lean it may run slightly hotter. Is it the stock cam or a performance unit? A camshaft installed retarded a couple degrees will make the engine run hotter. I have a bone stock 1968 GT/CS Mustang with a 289 and it never runs hot. I’ve also owned multiple Fords with 289-302 and have never had one run hot or overheat. Maybe a partial blockage somewhere?
94/95 GT covers/wp, and 96-01 Explorer, are noticeably unique. No mistaking them. 79-91 carb covers can be deceiving if you don't know, reverse rotation wp and has a mechanical fuel pump mount. But look like conventional covers. 86-97 'fuelie' covers have revere rotation and lack the fp mount. Lot of years that overlap, part of a Windsor's charm. Back to the Falcon.
Put a '17+ Silverado 5.3 PWM 16" electric fan with a PWM fan controller and be done with it. You have an air flow issue, and that mechanical fan ain't cutting it.
I have a 327 Chevy behind a parts store early Mustang radiator that started running warmer than it should, even with a 17" fan and a shroud. Tried a Flow Kooler high flow water pump and it didn't change a thing. Ended up getting an aluminum radiator with 2 rows of 1" tubes. I hate to admit it, because I don't like aluminum radiators, but it fixed my heating problem. Gary
I haven’t had one apart in a long time but do 302’s use a backing plate between the water pump and cover? 429-460 use and if it’s not in place the engine won’t circulate the coolant properly.
289/302/351 covers do. Later 94/95/Exploder do not, cover is part of the pump housing. Dunno about Fairlane V8 or Challenger variants. 221/260s can have some one year only bits.
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