New Cleveland Coolant Aluminum Restrictor Plate Mod

[70Machboy]

I’m surprised that nobody in this VMF forum has discussed or even mentioned what the Cougar Cleveland group has been talking about for months now. It was developed by a Pantera owner. As the joke goes: A Pantera would start to overheat the minute you drove them off the showroom floor. That was his motivation to improve the Cleveland cooling design. After some thorough researching he found that the Cleveland’s mating between the brass restrictor ring and the hat of the Cleveland specific thermostat were not always sealing and thus much of the coolant was stuck in a recirculating path within the block. Long story short, they’ve come up with a heavy aluminum restrictor ring (with a very small air bleed hole in the middle) that replaces the old brass ring in the Cleveland block. This new ring must be used with a standard Ford thermostat design (not the Cleveland specific) and this thermostat must have 2 to 3 holes (3/16” diam) drilled around the standard Ford thermostat’s perimeter (allowing warm-up coolant flow during the time the thermostat is closed).
The bottom line is that everyone that has tried this reports that it works and that it works really well! It’s like a major breakthrough in the Cleveland cooling system and nobody here is taking about it? So am I misinformed or what?

- Gary -

[22GT]

Well, the Pantera has the intakes for the radiators in the quarter panel. Not optimum. Couple that with, as it turns out, many Panteras had the radiator fans wired backward at the factory.

The usual problem in Mustangs is the wrong (non-cupped) thermostat, although occasionally somebody has thrown out the plate.

[TommyK]

Originally Posted by 70Machboy

I’m surprised that nobody in this VMF forum has discussed or even mentioned what the Cougar Cleveland group has been talking about for months now. It was developed by a Pantera owner. As the joke goes: A Pantera would start to overheat the minute you drove them off the showroom floor. That was his motivation to improve the Cleveland cooling design. After some thorough researching he found that the Cleveland’s mating between the brass restrictor ring and the hat of the Cleveland specific thermostat were not always sealing and thus much of the coolant was stuck in a recirculating path within the block. Long story short, they’ve come up with a heavy aluminum restrictor ring (with a very small air bleed hole in the middle) that replaces the old brass ring in the Cleveland block. This new ring must be used with a standard Ford thermostat design (not the Cleveland specific) and this thermostat must have 2 to 3 holes (3/16” diam) drilled around the standard Ford thermostat’s perimeter (allowing warm-up coolant flow during the time the thermostat is closed).
The bottom line is that everyone that has tried this reports that it works and that it works really well! It’s like a major breakthrough in the Cleveland cooling system and nobody here is taking about it? So am I misinformed or what?

- Gary -

It's been discussed.

351c overheating with no thermostat

[Klutch]

I think 22GT makes a good point. (As always.) It's probably more of a Pantera problem than a 351 Cleveland problem.

I used to drive a '70 fastback with a Cleveland. I drove it through brutal Oklahoma summers with the A/C pumping. It had a factory radiator and it never overheated.

[Blues Power]

we're the oroignal owners of my C and it never ever over heating as a result of that.

I had other issues over the years d like a plugged rad, stuck stat or cracked tank but the plate never gave me any porbs.

[70Machboy]

TommyK – YOU make reference to the MurcuryCougar.net forum discussion page where THEY discuss this mod, but I see nowhere where we Mustang guys have either thoroughly discussed it or even given it a try. Granted, perhaps Mustangs are not in need of it as much as the Pantera crowd, but then neither are the Cougar Cleveland drivers, yet many of them with overheating problems (and there’s been Mustangs occasionally contending with this situation too) have apparently solved this by changing out their brass ring for this new aluminum restrictor and installing the standard Ford thermostat with the holes drilled in (as previously described). The reason I’m putting this up for discussion is that:
1.) If it does actually remedy to any degree overheating problems (due to poorly matching hat and ring surfaces, etc), then we should be spreading the word as well.
2.) I am building a rather stout Cleveland for my 70 Mach but want my original factory “appearance” under the hood. The factory installed the smaller radiator (non-A/C car) in my Mach and I’m concerned that my disguised stoker Cleveland build might overtax this standard sized radiator, although it is a new 3-core build.

So that’s where I’m coming from.

- Gary -