Well folks, you get to benefit from another situation I found myself in. The day before I was supposed to drive to Arkansas from Kentucky, my water pump decides to reveal to me that it was leaking. I had been smelling antifreeze but it wasn't leaving any drops on the floor. Well, that finally changed at the most inopportune time.
Some info on how to check for a leaking water pump. First of all, if you smell antifreeze, you have a leak. Period. You may not see it, see coolant on the ground or be able to locate it but trust me, you have a leak. I think I have managed to have a leak in every possible common location:
Here's the deal with detecting a water pump leak on the C5. The fluid will not drop to the floor directly under the water pump unless you have a really heavy leak. It will land on the belt or belt pulley and sling to one side of the car (most likely the driver's side because of the direction that the belt travels). I didn't know that as I kept checking dead center of the engine on the garage floor. My leak was extremely small up until the point that I actually found it. Hey, I'm old school and my previous experience taught me to check dead center of the engine on the garage floor. Now I know better. :lookinup:
This turned out to be a rather easy repair compared to some that I have done. I would easily recommend a shade tree mechanic take this on as long as you have one very important tool: hose clamp pliers. Don't even attempt this repair without them as there are quite a few hose clamps that you have to remove. Those things will take you forever to remove with a pair of pliers. Don't waste your time, buy a nice pair of hose clamp pliers with the extension cable. You'll thank me later. You'll see them in the pictures below.
With all that said, let's get to the repair!
Tools needed:
This repair should only be done when the engine is cool or cold.
Step 1: Remove the air cleaner intake duct. This is actually done as a unit. You don't have to remove the entire thing as I did, you can just remove the air bridge but for me, it was quicker just to remove the whole thing since I know how. Here it is removed:
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To do this, pop up the pins that hold the air bridge onto the radiator shroud.
![Image]()
Unplug the mass airflow (MAF) sensor connector. Once you get it unplugged and the harness is disconnected from the clip that holds the harness down, move it toward the back of the engine out of your way.
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Remove the air filter in order to make the next step simpler. As you can see, I'm a firm believer in the K&N filter.
![Image]()
This next part is kind of tricky the first time you do it. The air cleaner intake duct is held onto the front frame cross-member by 2 rubber grommets. The air box just pushes on and pulls off. The first time you do it is like pulling teeth because you really have to give it a tug. It gets easier to do once you've done it before. See pictures below.
![Image]()
![Image]()
You will also need to unplug the Secondary Air Injection (AIR) hose. The bottom part of that hose simply pulls apart from the top part if you twist it back and forth.
![Image]()
Last of all, loosen the screw that holds the air bridge onto the throttle body.
![Image]()
Once you get all this stuff disconnected, separated and unplugged, the air cleaner intake just simply lifts out of the engine bay. Put it to the side.
Step 2: The first thing you need to do here is look at how the accessory belt is routed. Take pictures of it from various angles so that you will have something to look at when it comes time to put it back on. That's what I do before disassembling anything.
Remove the accessory belt from the accessory tensioner pulley and allow it to drop toward the bottom of the engine. There is no need to remove it all the way so don't make more work by doing so. To remove it, use the 15mm socket and rotate the pulley clockwise (toward the driver's side), until you can slip the belt off the tensioner.
![Image]()
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Step 3: Drain the cooling system. In order to do this, you will need to raise the car. for those who don't have a lift, here's the way I do it.
A) Drive the front of the car up on some 2X12's.
![Image]()
B) Using a low profile jack that I got from Harbor Freight, I center a 2X4 on the jack plate and run it under the front of the car.
![Image]()
![Image]()
![Image]()
Once in place and lifted, I support the car with jack stands.
![Image]()
I follow the same exact procedure for the rear of the car, making it slightly higher for draining purposes.
Warning: Pay special attention to the front jacks as you raise the rear. They could topple over if you get to extreme with your lift height!!!
![Image]()
Now I have all kinds of room to work under the car.
![Image]()
Remove the overflow tank cap and get your safety glasses on. Remember, safety first! :thumbsup:
![Image]()
![Image]()
The actual draining of the system is pretty easy. You simply loosen the drain cock (hey, I didn't name it... that's what it's called) and you will see the fluid begin to flow. You will turn it counter-clockwise. Do not completely remove the drain cock, just loosen it until the antifreeze starts flowing real good. Now go have Dagwood Pizza and your favorite drink because it will take the fluid a little bit to completely drain..
![Image]()
![Image]()
Once all of the coolant has drained, close the drain cock and lower the car. You can reuse your old coolant if you want to but if it wasn't changed recently, I don't know why you would. Don't be a cheap azz, buy some new fluid for your baby. Don't get the 50/50 stuff because you're paying for water, which is free (however, if you don't have access to distilled water, buy the 50/50 stuff). Other than that, buy the full strength stuff and dilute it with distilled water. You can use A 50/50 mixture of clean, drinkable water but use only GM Goodwrench® DEX-COOL® or Havoline® DEX-COOL® silicate-free coolant. It takes approximately 11.9 liters (12.6 quarts) to refill the cooling system.
Some info on how to check for a leaking water pump. First of all, if you smell antifreeze, you have a leak. Period. You may not see it, see coolant on the ground or be able to locate it but trust me, you have a leak. I think I have managed to have a leak in every possible common location:
- The "T" connector located on the surge tank (it usually cracks).
- The upper hose connector at the top of the radiator. It develops a hairline crack. There's a TSB that has you polish it out and not replace the radiator. I replaced my radiator instead because it had over 100,000 miles on it.
- The water pump.
Here's the deal with detecting a water pump leak on the C5. The fluid will not drop to the floor directly under the water pump unless you have a really heavy leak. It will land on the belt or belt pulley and sling to one side of the car (most likely the driver's side because of the direction that the belt travels). I didn't know that as I kept checking dead center of the engine on the garage floor. My leak was extremely small up until the point that I actually found it. Hey, I'm old school and my previous experience taught me to check dead center of the engine on the garage floor. Now I know better. :lookinup:
This turned out to be a rather easy repair compared to some that I have done. I would easily recommend a shade tree mechanic take this on as long as you have one very important tool: hose clamp pliers. Don't even attempt this repair without them as there are quite a few hose clamps that you have to remove. Those things will take you forever to remove with a pair of pliers. Don't waste your time, buy a nice pair of hose clamp pliers with the extension cable. You'll thank me later. You'll see them in the pictures below.
With all that said, let's get to the repair!
Tools needed:
- Hose Clamp Pliers
- 3/8" 10mm Socket and Ratchet
- 3/8" 15mm Socket
- Flat Head Screwdriver
- Dielectric Grease or Vaseline
- Radiator Hose or White Lithium Grease
- Safety Glasses
- Another socket for the thermostat bolts but I forgot what size it was! :lookinup:
- These instructions! :thumbsup:
This repair should only be done when the engine is cool or cold.
Step 1: Remove the air cleaner intake duct. This is actually done as a unit. You don't have to remove the entire thing as I did, you can just remove the air bridge but for me, it was quicker just to remove the whole thing since I know how. Here it is removed:
To do this, pop up the pins that hold the air bridge onto the radiator shroud.
Unplug the mass airflow (MAF) sensor connector. Once you get it unplugged and the harness is disconnected from the clip that holds the harness down, move it toward the back of the engine out of your way.
Remove the air filter in order to make the next step simpler. As you can see, I'm a firm believer in the K&N filter.
This next part is kind of tricky the first time you do it. The air cleaner intake duct is held onto the front frame cross-member by 2 rubber grommets. The air box just pushes on and pulls off. The first time you do it is like pulling teeth because you really have to give it a tug. It gets easier to do once you've done it before. See pictures below.
You will also need to unplug the Secondary Air Injection (AIR) hose. The bottom part of that hose simply pulls apart from the top part if you twist it back and forth.
Last of all, loosen the screw that holds the air bridge onto the throttle body.
Once you get all this stuff disconnected, separated and unplugged, the air cleaner intake just simply lifts out of the engine bay. Put it to the side.
Step 2: The first thing you need to do here is look at how the accessory belt is routed. Take pictures of it from various angles so that you will have something to look at when it comes time to put it back on. That's what I do before disassembling anything.
Remove the accessory belt from the accessory tensioner pulley and allow it to drop toward the bottom of the engine. There is no need to remove it all the way so don't make more work by doing so. To remove it, use the 15mm socket and rotate the pulley clockwise (toward the driver's side), until you can slip the belt off the tensioner.
Step 3: Drain the cooling system. In order to do this, you will need to raise the car. for those who don't have a lift, here's the way I do it.
A) Drive the front of the car up on some 2X12's.
B) Using a low profile jack that I got from Harbor Freight, I center a 2X4 on the jack plate and run it under the front of the car.
Once in place and lifted, I support the car with jack stands.
I follow the same exact procedure for the rear of the car, making it slightly higher for draining purposes.
Warning: Pay special attention to the front jacks as you raise the rear. They could topple over if you get to extreme with your lift height!!!
Now I have all kinds of room to work under the car.
Remove the overflow tank cap and get your safety glasses on. Remember, safety first! :thumbsup:
The actual draining of the system is pretty easy. You simply loosen the drain cock (hey, I didn't name it... that's what it's called) and you will see the fluid begin to flow. You will turn it counter-clockwise. Do not completely remove the drain cock, just loosen it until the antifreeze starts flowing real good. Now go have Dagwood Pizza and your favorite drink because it will take the fluid a little bit to completely drain..
Once all of the coolant has drained, close the drain cock and lower the car. You can reuse your old coolant if you want to but if it wasn't changed recently, I don't know why you would. Don't be a cheap azz, buy some new fluid for your baby. Don't get the 50/50 stuff because you're paying for water, which is free (however, if you don't have access to distilled water, buy the 50/50 stuff). Other than that, buy the full strength stuff and dilute it with distilled water. You can use A 50/50 mixture of clean, drinkable water but use only GM Goodwrench® DEX-COOL® or Havoline® DEX-COOL® silicate-free coolant. It takes approximately 11.9 liters (12.6 quarts) to refill the cooling system.
