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Hi. I recently replaced my water pump on my 2009 GS350. I noticed however the new pump is leaking around the seal. I was told by the guy at the auto store to use the sealant so i applied it. However after i noticed the leak around the new pump i researched and saw a article saying that the newer gaskets dont require sealant and that it could cause a leak around the seal. Was wondering did you apply any to yours or you just installed the gasket alone?
I did not apply any extra gasket/sealant other than the gasket provided with the waterpump. Driven over 500 miles with new waterpump and no signs of leaking anywhere.
Originally Posted by professorm
Is there any need to change the belt tensioner as preventative maintenance while replacing the other parts?
Is there need to replace the thermostat?
There is no need to change the belt tensioner or thermostat but I just figured why not since my buddy gets employee pricing at longo lexus on parts and I enjoy DIY and wrenching.
I went with the Gates brand like ibidu1 and alchemist suggested. You can get it from Walmart and or amazon.
There is no need to change the belt tensioner or thermostat but I just figured why not since my buddy gets employee pricing at longo lexus on parts and I enjoy DIY and wrenching.
I am at 120k miles now.
Has there been any reports of thermostat failing? When I told my mechanic that I was changing the water pump and not the thermostat, he laughed at me. Of course, he is a general mechanic and not Lexus specific, so I told him that the water pump is the weak point on this car, but everything else is solid, including the thermostat.
Conventional knowledge had it that you always change the thermostat on any vehicle around 100k miles. That was a part of my previous Honda’s 100k miles tune up.
Why don’t we change the thermostat? Let’s say I am 200 miles away from home when it fails, does it ALWAYS faily open where I can make it back home? Is it such a solid part that I don’t even need to worry about it even at 200k miles?
Has there been any reports of thermostat failing? When I told my mechanic that I was changing the water pump and not the thermostat, he laughed at me. Of course, he is a general mechanic and not Lexus specific, so I told him that the water pump is the weak point on this car, but everything else is solid, including the thermostat.
Conventional knowledge had it that you always change the thermostat on any vehicle around 100k miles. That was a part of my previous Honda’s 100k miles tune up.
Why don’t we change the thermostat? Let’s say I am 200 miles away from home when it fails, does it ALWAYS faily open where I can make it back home? Is it such a solid part that I don’t even need to worry about it even at 200k miles?
Can my engine survive a thermostat failure?
When I did my water pump 4 years ago, my thermostat wasnt that old. At that time oem were pretty expensive! Since then the prices have dropped! But yes, you should replace the thermostat, if one were to seize lock up it would block coolant flow. There is a small hole thats usually drilled into thermostats that allows some coolant to pass.
When I did my water pump 4 years ago, my thermostat wasnt that old. At that time oem were pretty expensive! Since then the prices have dropped! But yes, you should replace the thermostat, if one were to seize lock up it would block coolant flow. There is a small hole thats usually drilled into thermostats that allows some coolant to pass.
Thanks! I ordered the OEM Thermostat 16031-31020 on ebay for $27.59
I took screenshots from EZ12a’s video that he linked above to help me with the specs. I hope he doesn’t mind. I can remove the screenshots if he requests. Torque values Inlet hose Water pump
Thanks for the excellent write up. I was able to successfully change the water pump, belt, thermostat, coolant and idle pully. The only thing I wish I changed was the pully on the tensioner.
The only thing missing from this post is the torque values of the water pump.
waterpump 12mm bolts = 15 ft *lbf
waterpuml 10mm bolts = 6.75 ft*lbf
I have 123k miles. The dealership said that my water pump was starting to make slight noise, but it was not leaking. I now have peace of mind with it changed.
I bought all my parts from RockAuto and ebay. The entire job cost me $230.
By the way, I went to get my coolant from the Toyota dealership thinking it would be a good price. I ended up paying $63 for 2 bottles of coolant. The same thing was on eBay for $42, but I ended up buying the $46 coolant to get slightly faster shipping. I did not know that I could buy fluids online as well. I got mine in 2 days.
I used the distilled water to flush the radiator/cooling system with the original water pump AND with the new water pump (probably not necessary but I figured why not).
I have 224k miles 07 GS450h on my stock oem water pump and I intend to do it at 250k miles.
Thanks for the great write up, and all of the additional info. I will change the water pump, inlet assembly, tensioners, belt, stat and coolant this next weekend.
Wife has a 07 with 120K on it currently. I will follow up with any helpful info if found.
Thanks again everyone
Question, your thoughts on the following inlet & outlet
assembly’s. Should these be changed as well?
Thanks for the great write up, and all of the additional info. I will change the water pump, inlet assembly, tensioners, belt, stat and coolant this next weekend.
Wife has a 07 with 120K on it currently. I will follow up with any helpful info if found.
Thanks again everyone
Question, your thoughts on the following inlet & outlet
assembly’s. Should these be changed as well?
Water Inlet - Lexus (16031-31020)
I would only replace that inlet, as it is your thermostat. You can find these oem on ebay pretty cheap.
A huge thanks to the OP and for the great info posted in this thread. Swapped out the wp on my 07 GS450h. A heads up to those looking to do this on theirs, get the right belt as it's different(shorter) than the GS350 and you DO NOT need the idler pulley. The 450h doesn't have it as there is also no alternator. I also had issues with the o-ring on the water inlet housing. The one included with my waterpump was slightly missized and I ended up having to get a universal one to replace. Also for those thinking not to drain their coolant, it can be done but will be unnecessarily messy. If I were to do it again, I would just drain off a good portion of the coolant to simplify things. Hope this helps someone and thanks again guys!
-Steve
The GS450h does have an idler pulley assembly and it is ribbed , there is 1. This is needed to put tension on the belt for the crank and waterpump pulley. Lexus Part No.: 16620-31060. I dont see a separate part number for just the pulley but there is a company on Ebay that makes replacement pulleys if you are worried about the bearings in it.
The GS350 have 2 that are not ribbed. These pulleys can be replaced.
Awesome right up and additions.
Does anyone happen to know the torque spec for the thermostat.
I went through the thread a few times and didn’t see it.
I’m doing my water pump right now and also changing the stat and hoses but I could not find the spec on the stat nuts.
Any info is greatly appreciated. And if I find it I will post it as well.
*** Also notice that only two of the 10mm bolts have a blue indicator for thread-locker. But all of the 12mm bolts have what appears to be a pipe dope of some sort.
Awesome right up and additions.
Does anyone happen to know the torque spec for the thermostat.
I went through the thread a few times and didn’t see it.
I’m doing my water pump right now and also changing the stat and hoses but I could not find the spec on the stat nuts.
Any info is greatly appreciated. And if I find it I will post it as well.
*** Also notice that only two of the 10mm bolts have a blue indicator for thread-locker. But all of the 12mm bolts have what appears to be a pipe dope of some sort.
Anyone have any insight?
Any bolts connected to the engine (that vibrates) I would use blue loctite. I dont know the torque specs, but for something small like the 10mm head bolts I would snug them up by feel, you will be ok.
When I did my water pump years ago, I didnt use a torque wrench at all.
01-30-19 | 12:21 AM
Hi. I recently replaced my water pump on my 2009 GS350. I noticed however the new pump is leaking around the seal. I was told by the guy at the auto store to use the sealant so i applied it. However after i noticed the leak around the new pump i researched and saw a article saying that the newer gaskets dont require sealant and that it could cause a leak around the seal. Was wondering did you apply any to yours or you just installed the gasket alone?
