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How to prime water pump?

  • Thread starter Thread starter ZBlue89
  • Start date Start date May 6, 2009

ZBlue89

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Apr 14, 2009
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May 6, 2009
#1
  • May 6, 2009
  • #1
I changed the radiator on an 89 mustang and drained all the fluids including out of the water pump. I am refilling it now and the water doesn't seem to circulate. I was told by a buddy that it has "air pockets" and that the water pump would need to be primed first.

If this is true, how do I prime a water pump?

 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
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108
Chicagoland
May 6, 2009
#2
  • May 6, 2009
  • #2
You don't really prime the pump, but rather "burp" the system. Toss the front end of the car on some jackstands, remove the radiator cap, and let the car come up to operating temperature with the cap off. Grab a big funnel and put it in the radiator fill (I have one that fits tightly in the hole) and start pouring antifreeze in while squeezing the upper radiator hose frequently, so bubbles can make their way to the radiator, and out the fill hole. It's important that the car be on stands, so the radiator cap is the highest point in the system, so that any bubbles can make their way to the top.
 

S&B

I hate my CT. :(
10 Year Member
Dec 18, 2005
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Cheesehead
May 6, 2009
#3
  • May 6, 2009
  • #3


it might take a bit of running for the motor to come to temp and the thermostat to open. once it does you will know right away. When i use this method i let the car run at temp for 3 or 4 min before I cap it off.

sounds to me like you have pully issues make sure every thing is routed right, take a video or pix and post them up that will help you out
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
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May 6, 2009
#4
  • May 6, 2009
  • #4
It's really easy to over fill the system before the thermostat opens so don't get carried away.
 

NIKwoaC

中國製造
15 Year Member
Oct 31, 2006
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Chengdu Province
May 6, 2009
#5
  • May 6, 2009
  • #5
I'll add to this...


Something I like to do just for peace of mind is drive the car around the block and pop the cap off again to see where the fluid is. Don't go too far, you don't want to be stranded with a hot car. Repeat until there is no noticeable drop in fluid level after the short drive. I've found that sometimes helps get all the air out of the system better than just raising the front end.
 

LiquidGT

Member
Oct 8, 2007
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Near STL hell
May 6, 2009
#6
  • May 6, 2009
  • #6
I like to do all of the above to make sure there's no air left in the system.

Sometimes I wonder if it would be a good idea to tap in a bleeder screw on top of the EGR cooler; since its the highest point in the cooling system?
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
6,945
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Northern KY
May 6, 2009
#7
  • May 6, 2009
  • #7
You can also just rev the engine in neutral while it's on jack stands...that gets the water pump going faster and will help burp it. Make sure it's up to running temp and the thermostat is open first.
 

ZBlue89

New Member
Apr 14, 2009
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0
Buffalo
May 6, 2009
#8
  • May 6, 2009
  • #8
Thanks

I'll give that a try as soon as I get my pulley issue figured out. Thanks guys. I'll post again soon.
 
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