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onetrick56's 1964 Grand Prix

2020 September
of the Month

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Question

1966 lemans 389 aluminun three core radiator with aluminun 18 inch fan and shroud. Fan is 1 inch behind radiator runns 210

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What is the temp setting for your thermostat? I like to recommend using a wide-mouth thermostat from Mr. Gasket, it flows more coolant that a stock OEM style thermostat. How fresh is the motor and/or the water pump?

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I took the thermostat out and the water pump is new. It has a stamped impeller and the divider plate is about 3/8 away from impeller. I am waiting for a cast impeller water pump and I will bend the divider plates closer when the water pump is delivered. I will let you know how it works. Thanks for the info

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Here is a tip from Wallace Racing regarding the divider plate. Not saying that is your problem but it is something you can check since you are already waiting on a new water pump.

http://www.wallaceracing.com/water-pump-mods.php

 

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IndymanJoe had a good thread on this subject a couple years ago.

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Will let you know new water pump coming in Friday.  I also am going to install a 3000 cfm pusher in front of the condenser as its a ac car. You guys are great on the info.

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On 5/27/2020 at 8:21 AM, jimbobob said:

I took the thermostat out and the water pump is new. It has a stamped impeller and the divider plate is about 3/8 away from impeller. I am waiting for a cast impeller water pump and I will bend the divider plates closer when the water pump is delivered. I will let you know how it works. Thanks for the info

Ok a couple things strike me. One depending on several things, taking the thermostat out can, not always, but can have a negative impact on engine temp! Pulley size, water pump design and radiator type/design can and does impact coolant flow! If the the combination allows free movement of the coolant it can circulate the coolant to fast never allowing it to stay in the radiator long enough to cool. If the combination causes a restriction in the right place it can cause cavitation, which can act as a type of air lock that causes heating problems. Sometimes it will even allow coolant to move through an engine in a non uniform manner causing localized heating because of areas that become stagnant in movement.

Also you mention that you have a shroud and that the fan is 1” away from the radiator! I presume the shroud is deeper than 1”? If so and the shroud is a typical shroud that is built as a tapper, then the fan blade tips need to be placed at the smallest portion of the shroud opening. Otherwise the fan will actually cause cavitation of the air flow and become very in efficient at moving air through the radiator! To a degree it will act like blocking the front of the radiator to restrict air flow!

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Well I received my water pump with a cast impeller and bent the divider plate ..040 thousandths  (less than 1/16th) and installed it and did nothing else and started it up and let run 30 minutes and it never went over 180 degrees (prior to change in 15 minutes it would be 210 degrees). Took it for a spin and never got over 180. I am going to put a 160 high flow thermostat back in it  and fill with anti freeze. I want to thank you guys for all the help you turned my way and very much appreciative as I was at a loss. THANK YOU 

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We're always willing to help a buddy out.

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We’re always glade when things work out! The divider plate proximity to the impeller is another example of cavitation that creates flow disruptions. 
 

Way to go Frosty!

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Posted (edited)
3 hours ago, Last Indian said:

We’re always glade when things work out! The divider plate proximity to the impeller is another example of cavitation that creates flow disruptions. 
 

Way to go Frosty!

Thanks bud.

Good luck jimbobob.

Edited by Frosty
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