or 13 psi cap.
stock radiator cap pressure
Ford Parts Specialist
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From: Simi Valley, CA
No such thing as a 9 lb. cap.
E5TZ-8100-A (replaced B2VY-8100-A & C9AZ-8100-A) .. 13 lb. Radiator Cap (Motorcraft RS-62).
Applications: 1961/96 F100/350, Econoline & 1966/96 Bronco / Myriad 1956/91 Passenger Cars.
E5TZ-8100-A (replaced B2VY-8100-A & C9AZ-8100-A) .. 13 lb. Radiator Cap (Motorcraft RS-62).
Applications: 1961/96 F100/350, Econoline & 1966/96 Bronco / Myriad 1956/91 Passenger Cars.
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From: Simi Valley, CA
Wonderful, but this is FTE = Ford Truck Enthusiasts, the OP has 1983 F150.
So whatever radiator cap a Mercedes, Wartburg, Maybach-Zeppelin, Borgward, Wanderer, VW, Audi, Horch and etc German cars has, doesn't apply here.
So whatever radiator cap a Mercedes, Wartburg, Maybach-Zeppelin, Borgward, Wanderer, VW, Audi, Horch and etc German cars has, doesn't apply here.
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From: Ft. Worth
13 PSI
13 lb radiator cap is what's called for according to my trucks owners manual...However, I have found that since I have installed a Champion aluminum radiator with 50/50 mix of fleetcharge and distilled water a 7 lb radiator cap seems to work better.
I am not sure how this is working, but with the 7 lb'er it seems that the coolant is being cycled from the block to radiator and back to block at a faster rate which I think is helping to keep my truck running cooler particularly when towing my 5'ver. Like I said...I am not sure exactly what's going on. I know the new radiator sure helps, but even so it seems the thermostat should regulate the flow around 192 degrees or so and now my fan clutch never kicks in anymore...
Maybe I am just nuts, but I know the fan clutch is good, so like I said the 7 lb'er seems to have changed the dynamics somehow...
I am not sure how this is working, but with the 7 lb'er it seems that the coolant is being cycled from the block to radiator and back to block at a faster rate which I think is helping to keep my truck running cooler particularly when towing my 5'ver. Like I said...I am not sure exactly what's going on. I know the new radiator sure helps, but even so it seems the thermostat should regulate the flow around 192 degrees or so and now my fan clutch never kicks in anymore...
Maybe I am just nuts, but I know the fan clutch is good, so like I said the 7 lb'er seems to have changed the dynamics somehow...
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beercan, it makes sense for the radiator itself to flow better because it doesn't have 25 years of corrosion, but the different cap pressure can't affect the flow of coolant. if/when it does start to overheat, your lower pressure cap will allow it to boil over at a lower temp than the 13# cap
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From: Ft. Worth
Boiling Over
beercan, it makes sense for the radiator itself to flow better because it doesn't have 25 years of corrosion, but the different cap pressure can't affect the flow of coolant. if/when it does start to overheat, your lower pressure cap will allow it to boil over at a lower temp than the 13# cap
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From: Sheffield, AL
Like this?
Pressure and Boiling Points of Water
Be aware that this chart is for water, not antifreeze, which makes the boing points significantly higher, depending on mix strength.
Last edited by 1986F150six; Nov 13, 2012 at 01:28 PM. Reason: Spelling correction
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From: Ft. Worth
Boiling Points
Like this?
Pressure and Boiling Points of Water
Be aware that this chart is for water, not antifreeze, which makes the boing points sinificantly higher, depending on mix strength.
Pressure and Boiling Points of Water
Be aware that this chart is for water, not antifreeze, which makes the boing points sinificantly higher, depending on mix strength.
Anybody know of such a chart?
Oops...Nevermind...It is on my anti-freeze bottle...a 50/50 mix for me gives a boiling point of 265 degrees...so I guess I should go back to a 13 or 16 lb cap...to see if I can get my operating temp up to 180 minimum...right now...using a new aftermarket gauge I never get above 175 degrees...and this is with new radiator, pump, t-stat, and hoses...
Any ideas guys?
Thanks
Last edited by BeerCan500; Nov 13, 2012 at 01:18 PM. Reason: added info
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From: Ft. Worth
T-stat
As far as outside ambient temps...they have been in the high 80's here in Texas...