DIY 2nd Gen Water pump replacement

Super. Thanks iroh!

 

awesome write up! i tried to rep, but it isn't letting me on my phone...

 

Great write-up! I'll be using this when I replace my wp this weekend. Have a couple quick questions though -

on the service manual it says to torque some bolts (A) to 80 in-lb (6.7 ft-lb) and other bolts (B) to 17 ft-lb. I'd hate to over-torque or under-torque some of them. Do you know which is which? Also, on the service manual it shows to install a new gasket on the water pump. What gasket is this? I already have the outlet o-ring that is shown. Does the Aisin wp come with this other gasket?

thanks!

 

Sorry I don't know about the bolts. It seems like there are fewer, longer bolts (A). And many shorter bolts (B) around the perimeter. Someone please verify.

I believe the gasket they are referring to is the outlet gasket. The water pump does NOT come with this

 

I just replaced the serpentine belt and one of the top idlers on my wife's 08 4Runner with the 4.0L, it has 86K miles. I noticed some pink crusty dried antifreeze below the water pump. The reservoir was down a half inch. I thought this pump is done and needs replaced. I filled the reservoir to the full mark. The next day I was on a 4Runner website and found this:

Could you guys be experiencing this?
Some Toyota water pumps are now designed with a debris ejection path that may some leakage under normal conditions. Interesting......

TSB-0117-11 pdf

Water Pump Inspection and Diagnostic Tips Issued: 9/1/11

Applies to: 2003 – 2011 4Runner 2005 – 2011 Tacoma 2011 Highlander HV 2008 – 2011 Highlander 2006 – 2011 RAV4 2007 – 2011 Tundra

Excerpt: "Temporary Leaks If debris becomes trapped between the mating ring and seal ring a small gap is formed. This allows coolant to bypass the mechanical seal, flow into the fluid catch pocket, and drain out of the weep hole. This condition is temporary and will no longer be present once the debris is crushed or works its way out of the seal. Water pump replacement is not necessary.

If debris was trapped between the seal ring and mating ring an abrasion mark may have been left on the mating ring surface. This abrasion mark does not affect sealing performance due to the large sealing surface of the mating ring. Once the debris is no longer present the mechanical seal performance will return to normal operation. Water pump replacement is not necessary."

I am thinking this is what happened to my wife's 4Runners water pump, a week later the reservoir is still up to the full mark and not going any lower. I am still going to be ordering all the parts to change out the pump, thermostat, and top and bottom radiator hoses because I know I will be eventually changing it.

 

Nice find with the TSB. I was in a different situation as mine had dropped to Low a couple times. I would just keep an eye on it I it is only weeping a little.

 

I noticed the same thing in terms of my res tank falling below the "Full" line but it would take 2-3 weeks for me to notice a change after topping it back off. This 2-3 week cycle went on for a couple months so I decided to change everything out. Mine was around 85k miles. In those couple months, nothing went wrong with the truck, I was just wasting expensive coolant. So I'd agree with medusa and just monitor it for a while and see if it keeps happening.

 

When did they start putting a "weep hole" in water pumps? I bet a lot of water pumps are changed prematurely because people see antifreeze coming from the water pump and think the pump has too be bad. My daughters 2009 Hyundai has 90K miles so I also was investigating about her water pump. Yep, her water pump also has a weep hole and can do the same.

 

This will come in handy one day...thanks Ken

 

Great write up, any approximate time on this replacement.

 

I think all water pumps have weep holes. It's normal to see a little bit of coolant residue around it.

 

Subbed. Thanks for the write up!

 

Did this last weekend. (Flush, t stat, water pump) Thanks for the write up. It really helped!

Fyi i ordered the aisin water pump and it came with the two gaskets.

 

Do I NEED to replace the pulleys/tensioner when I replace the pump? Reason I ask is that I am having mine replaced under my extended warranty I purchased through the dealership.

It will cost me another $200 so was just curious. They aren't making any noise that I can tell.

Thanks!

 

Changed my pump, belt, thermostat and coolant with help from the posting. Got nervous in the beginning but its an easy job. Used my phone to video the belt routing did not remove air filter plenum and was able to reach both block drains with a 3 foot extension on a universal socket. Great write up!

 

SUb'd

 

When I did the water pump, I also changed to an E-fan, all NST lite pulleys, idler pulleys, and silicon radiator hoses. I had a lot of room to work with. Also when removing the bolts use the new water pump as your bolt holder and replace where it would need to go. Just transfer the bolts over to the old pump and when installing the new waterpump go one bolt at a time. You should have all the gaskets with the AISEN water pumps. If your changing your waterpump at 100k and thinking about doing the pulleys, just do it while your in your engine. why wait another 10-20k to hear the squeaking.

 

sub'd. I haven't driven my truck for a few days now because it is making an obnoxiously loud noise and I think it's the water pump. Thanks for the nice looking write up OP..Unfortunately it's looking like I'll be using it soon.

 

Great writeup, thanks.

 

As far as these failing, mine made a turkey call noise, and I could hear it over my exhaust, and its pretty loud... 100k miles when I did it