Fox Cooling System Issues/questions

Hi all,
On my 90 GT I'm running a March Performance UD pulleys Kit 1015 I have no issues until I removed the AC system. I wanted to keep the PS pump down in the stock position but the problem is with the WP pulley, the belt rubs when loading the belt tensioner. To solve this problem I replaced the pulley with the stock one and the rubbing problem was solved, the belt runs fine. Well another problem occurred, the temperature went up close to 210 degrees.
I have a 195 degree thermostat because I want to be around 195 - 200 deg. I'm running a Taurus fan with a Delta DC Controller and a Griffin aluminum radiator.
I believe I tried a 180 deg thermostat and the temp went up...
I read that many people run UD crank pulley and stock all the rest of the pulleys and they said no problems, others said they even run a 93 cobra pulley which is even smaller than the GT and no problems.
My 90 gt stock water pulley is smaller than the March one so the pump spins faster, so it should cool down better, or maybe too fast that the water don't spend enough time in the Rad to cool it down?.. Am I missing something here?

PLEASE HELP!!!
 
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You need to relocate the PS to where the AC was andput the stock pulleys back on . U/D pulleys do nothing but cause cooling and charging issues. Are you turning the WP the wrong way now with your belt routing? The flat side of the belt should be riding on the WP pulley.

Tech_50belts.gif
 
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Thank you mikestang63 for your reply.
With the UD pulley kit I have no issues with either cooling or charging. The problem started when I started using the stock WP pulley for belt clearance.
I have the correct belt routing as per reverse WP.
I kinda like to keep the SP down there and the belt has enough clearance with the stock WP pulley, but if I still have issues with that I can always invert the tension on the tensioner and put a grooved pulley to pull the belt upwards instead of pushing down on it.
The rising of the temp doesn't make any sense to me, since the stock WP pulley is smaller than the one from the UD kit therefore it spins a tad faster and should in theory be cooling better, but I guess not.
Any other ideas will be greatly appreciated.
Thank you all!
 
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Even with the smaller WP pulley, it still spins slower due to the smaller crank.

Under drive pullies don't necessarily cause cooling issue, but they certainly expose any weaknesses in charging and cooling system if any exist.




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Thank you Mustang5L5

Well I have to say that just don't make sense.
If running the three UD pulleys from the Mach kit I don't see any cooling issues. Why by running a bit smaller water pump diameter will make the temp. to go up?
Here is my reasoning:
I was running this set up with no cooling issues:
UD crank pulley diameter is: 4 - 3/8"
UD Water pump pulley Diameter: 5 - 1/2"
Using a 1,000 rpm on the crank as a baseline, the water pulley will spin 795 rpm

Now I'm running this set up and the temp. got higher (WTF??):
UD crank pulley diameter is: 4 - 3/8"
STOCK Water pump pulley Diameter: 4 - 11/16"
Using a 1,000 rpm on the crank as a baseline, the water pulley will spin 933 rpm (138 RPM faster)

wouldn't I be in theory running cooler regardless of the UD status?
I'm just confused, to me it make sense that's why I plotted those numbers, but it seems to have an opposite effect in my cooling behavior.

I'll wait for your comments.
 
The water pump must run at or near the correct speed.
Too slow and it stays in the engine too long, too fast and it doesn't stay in the radiator long enough.
The key to the fox cooling system is when you get it right, don't mess with it.


Why did you remove the AC compressor?
 
Thanks 2000xp8
I started wondering about the water pump being running too fast as you mentioned. Even though that's the only thing that makes some sense, I'm not fully convinced, because with the stock pulleys using the same RPM baseline of 1,000 rpm, the water pump spins at 1,280 rpm, that is 257 rpm faster than what I'm running now.

The AC was removed because of three reasons:
A) Truly I never use the AC
B) One of the lines going to the compressor got broken, and.
C) the engine bay is cleaner and neater, plus easier to work on the engine with so many things less in your way
 
Thanks 2000xp8
I started wondering about the water pump being running too fast as you mentioned. Even though that's the only thing that makes some sense, I'm not fully convinced, because with the stock pulleys using the same RPM baseline of 1,000 rpm, the water pump spins at 1,280 rpm, that is 257 rpm faster than what I'm running now.

The AC was removed because of three reasons:
A) Truly I never use the AC
B) One of the lines going to the compressor got broken, and.
C) the engine bay is cleaner and neater, plus easier to work on the engine with so many things less in your way
Did you remove your AC condensor? If so, did you remove your radiator to access it or your front bumper? What I'm getting at is if you removed your radiator you could have air pockets in your engine and need to burp your system. :shrug:
 
Oh I know what your saying FoxMustangLvr.

No I didn't remove the condenser I just disconnected the hoses and used rubber plugs on the condenser connectors to avoid dust and foreign objects to contaminate de condenser for future AC re-installation.
I removed the compressor, accumulator, and hoses
 
Could there be a restriction/ blockage? Might have not been an issue when the pump was running slower-with it spinning faster , the moving coolant could be hitting the blockage and pushing back against the flow ? Just a thought
 
Could there be a restriction/ blockage? Might have not been an issue when the pump was running slower-with it spinning faster , the moving coolant could be hitting the blockage and pushing back against the flow ? Just a thought






Has fresh coolant.
image.jpeg
 
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Thanks 5.0droptop.
I thought about that but really want to keep the belt down low.
so here is my plan.
I will play with different setting on my Delta DC controller to bring the temperature down a bit and possibly change my thermostat to 180*. I will do this in an effort the keep the stock water pulley in place, if none of those two things work, then i will be forced to replace that pulley with the one I was running (complete March UD pulleys) and convert the belt tensioner to puller instead of pusher. This should be able to solve all of the issues I'm having.
I will publish whatever results.
 
Holly smokes!!!! That's some nasty stuff in that radiator!!!
I certainly don't have that, I run distilled water and about 30% anti freeze and since I have an aluminum radiator I use a radiator cap with a sacrifice rod to counter the electrolysis effect.
As a maintenance measure I will flush the cooling system and load it with new stuff.

Good suggestions from everyone, and I appreciate that!!!