ICE water pump replacement - Gen II

Thanks for sharing your experience. My 2004 is coming up on 150K miles so I will be replacing the engine and inverter coolants a second time, in the next week or so. I'll also replace the engine thermostat (original) and serpentine drive belt (for the second time) as a preventive measure. I bought the Lisle yellow plastic funnel a couple of years ago and am looking forward to trying it out.

I had previously bought a replacement engine coolant pump, anticipating I would need to replace the original - but so far the original is still working well. I appreciate your relating the need to wedge the coolant pump pulley in place prior to loosening the pulley bolts.

 

Thanks for this thread! I just followed this and the YouTube video, and saved myself probably $300.

I used a plain 10mm wrench to remove those 3 pulley bolts, with a 3/8" socket extension jammed into one of the pulley's holes as my "wedging" method.

My Lisle funnel worked ok, with the caveat that it leaked until I rotated the "radiator-cap" 180 degrees -- one of the sides just didn't have tight enough of a fit.

 

Were the pump bolts hard to remove or get to? I found the pulley bolts next to impossible to budge, soaking w. PB probably would have helped as well as using a ratcheting 10mm box wrench.

Mine was grinding like the OP reported and the mechanic said it was dangerous to drive and could fail at any moment. True?

 

The pump's three bolts and two nuts were not too hard to get to, but I had access to both the top and bottom since the car was raised up, and the engine undercover and front passenger-side tire were removed.

True. That sound indicates the pump bearing was falling apart.

I'm providing a link to my post about engine coolant pump and thermostat replacement here:
How to replace engine coolant pump and thermostat | PriusChat

 

Thank you, Patrick. I wish I would have had time to research and collect the right tools before attempting this the first time. I was panicking about the necessity of the repair and being January didn't help any. Why can't pumps fail in June?

But I was able to replace the serp. belt myself at a total cost of $9.63. Dealer wanted $35 for the belt alone. God knows how much they would charge for spark plugs+labor!

 

<dupe>

 

Yes, this is why my repair philosophy is to try to anticipate failures and take preventive measures where appropriate.

 

The pump bolts themselves weren't hard to remove, but they did require some contorting to get both hands in the area -- one to guide the socket and one to move the socket wrench. A ratcheting wrench wouldn't have really helped -- once the bolt/nut is loosened slightly, the rest is cake.

As long as the pulley itself is forced to not rotate, I found that the pulley bolts weren't horrible to remove either. (I only accessed via the top.)

It was 72 degrees and windless when I did the pump on Saturday -- warmer than our usual June weather here in the Bay!

 

After much research and watching several videos, I tackled the water pump and serpentine belt replacement on my 2006 Prius (with 126,000 mi) about a week ago.
There had been a noise coming from the right front side of the ICE and then coding P1121 eventually.
I will preface the next part by saying I've been out of work for over a month. Money has been tight and the last thing I wanted to do was spend money on an auto repair. I would have waited, but I had been concerned about a water pump failure and "what if" something happened to or from a job or interview.
I won't rehash the entire process, I just wanted to give some of my insights into this process. I'm not a mechanic and I have a limited tools..

• I purchased my Carquest branded water pump from Advance Auto online along with a serpentine belt. Cost with a coupon found on RetailMeNot saved me 30% off orders over $50, ended up being (after coupon) $42.xx.
• If you do not have a small 10 mm wrench, save money and go to Home Depot or Lowes (or really any hardware store). Advance Auto & Auto Zone both wanted $8-$10 for a 10mm wrench (round and crescent ends, non ratcheting) but at the hardware store a mere $1.97 and a small size to fit in this confined work area. I also purchased a small set of Hex wrenches which included size 6 for the radiator bleed.
• So when you disconnect the 12v battery negative, don't slam the hatch down. When the job is done, crawling over the flipped seats into a hot trunk to reconnect the battery isn't fun.. Lower hatch or leave open.
  
• I didn't raise the car. All work from the top. Im sure there will be flack when I say this, however I did not drain the entire coolant like some have done. My theory is if it's going to leak when I'm done; I would prefer the leak occur with the old coolant than the new. I can replace with new coolant later.
• Finding a pan to catch runaway coolant was a challenge. I used what I'm going to call a hospital wash pan. It's sort of like a shorter dishpan and it fit right under the car without clearance problems.
• Air intake "S" hose was always in the way even though I disconnected and removed air cleaner box.
• Reaching the lower bolts blindly with a short 10 mm (1/4 drive) socket can be done - in the future I would use a longer socket.
• Water pump pulley.. I used a screw driver angled in through the water pump pulley and wedged under tensioner this worked well..the pulley didn't rotate. Also my water pump pulley had chunky dried layers of coolant inside. I cleaned that off.
• Idler pulley.. I've read the challenges others experienced..I used a Kobalt 4 way wrench (rotating socket sizes on both ends of the wrench).. It happened to have a 14 mm socket and the wrench was long enough without having to add on any extension handle for extra leverage.
• Serpentine belt had it not been for another thread posting about changing the serpentine belt in 11 minutes, I would still probably be outside struggling..

 

Hi Patrick,
I have 2008 Prius with 96K miles in good standing order. I have never changed the ICE coolant. I can see a bit of dried coolant in the water pump pulley. So based on the mileage, I am thinking of replacing the Water Pump (gasket too) and Coolant. Do you recommend replacing the Radiator Cap and Thermostat? I changed the Serpentine belt about 15K ago.
Thanks,
Roberto

 

Yes.

 

Thank you Patrick!! I enjoy reading your posts.

 

I've just Replaced the Water Pump and Coolant successfully on my 2008 Prius with 96K. The older water pump was leaking a bit and leaving some residue on the pulley and creating a kind of crust on itself. Although the coolant level was fine, I did not want the car to fail and potentially overheat.
Thanks everyone for the recommendations, instructions and experiences. I used the Lisle Funnel which was great. Here are some of the steps I did and experiences I found. Many of them are similar to others with the exception of a check engine light I got when restarting the car after all work had been done.
1. I lifted the car to unscrew and put a side the driver's side fender liner to access the thermos
2. I disconnected a couple of connectors in the Thermos area. I think I only needed to disconnect one but I did the two.
3. I opened the valve and gathered 6.25 quarts exactly. Based on Patrick's experience I did not have to open the other drains. this procedure left the reservoir empty. I closed the Valve after.
4. I removed the Water Pump. I had ratchets and a small 10 mm box wrench. I wish I had an extended 10 mm wrench because I had little leverage with the small one. Anyway it still worked. Some coolant leaked at this point which was not recovered.
5. I Replaced the New Pump and Gasket. It might be worth checking the position of the older pump before removal so that you remember its position and do the same thing with the new one. I did not do this so it took me like 5 minutes to find the correct position of the gasket and pump. I was getting tired by then.
6. I put the screws back. I noticed that the Pump screws had some type of antiseize. Not sure what it was. I may have done a mistake but I added a bit of thread locker (the removable type). I was afraid that so much vibration could loosen up the screws at some point.
7. I replaced the Pulley. This was a bit more difficult to tighten with the small wrench box I had. I could not torque them to specs as I could not get the torque wrench in it. So this was a best effort. I then replaced the belt and ensured it was not too tight. By the way, I had replaced the belt about 20K ago so it looked like new, no glazing or cracks.
8. I was planning to replace the thermostat but I could not remove the hose and I was getting tired.
8. Using the Lisle Funnel and finding the correct lid, I started filling up the Radiator. I never left the funnel empty.
9. I removed the Relay to jump the electric Water Pump for about 20 seconds each time. I must have done it like 10 times like every 5 minutes.
10. This process took a long time(maybe almost an hour) but I could see the bubbles in the funnel as coolant made it in. I also squeezed the hose that goes from the radiator to the thermostat a couple of times. After like 50-60 minutes, no more went in and no more bubbles, so I closed the radiator with a new cap and filled up the reservoir. By the end, almost 6 gallons went in. So I felt most had gone in and I could take it for a drive when all people were sleeping.
11. I put the relay back.
12. I started the car in normal mode and planned to take it for a ride at 12 am.
13. The check engine came up as soon as I started the car. Using my ODBD2 connector it showed a code regarding coolant so I cleared it and never came back. I did not hear bubbles, possibly because the heater was at max speed and I couldn't hear them.
14. I drove for about 10 miles pushing it and set the heater at max speed and the hottest it could. Air was coming out hot fairly quickly.
15. Came back home and checked the reservoir level and it was fine. Let the car rest for the night
16. Next morning, I bled the system using the bleed valve and filled up the radiator. I also opened the radiator cap while the car was off. Some coolant came out and there seems to have been some air in between sections of coolant in the clear bleed hose. The width of my hose was small so I had to heat up the hose with a lighter and expanded it with something else so it could attach to the bleed valve.
17. I started the car and I heard some gurgles (like water flowing) but they disappeared quickly. I did this bleeding another time but the second time I did not see any coolant coming out from the valve. I then just added a tiny bit more of coolant to the reservoir and radiator they were both full.
18. At the end 6.25 quarts went in. After 6 days of city driving, I replaced the Black Cover that goes over the radiator and declared this project a success.
19. A couple of times, I spilled some coolant into the engine compartment when I removed the water pump and when I was refilling due to some splash. I used a water hose to wipe out all this residue.