I had the Toyota service folks flush and fill the antifreeze/coolant in my 05 Prius at 5yrs/60K miles. Afterward, I immediately noticed a strange newly developed sound coming from under the hood. I had them test drive it and they didn't hear it - neither did I when I drove off. A few days later a sort of a quaint diesel sound developed. The service folks told me they needed to replace the water pump, in the gas engine, due to bearing failure and that it was under warranty. So far, all is well now. Has anyone experienced water pump failure after coolant flush service on a Prius? Does anyone recommend not doing the flush when replacing the coolant?
I haven't heard about a water pump failure so soon after a coolant change. It sounds like the dealer took care of that issue for you. I would say that there's no need to have the coolant flushed for two reasons: 1. The first time that the 2G engine coolant needs to be changed is at 100K miles. Since you did this at 60K miles, the old coolant was still in good shape, so there should be no rust or other debris that needs to be flushed out. 2. If the engine coolant passages were flushed, that would be done with water and a flush chemical. After the flush, some water will be left in the engine. Based on my experience, around 3 quarts of fluid will remain. The Toyota SLLC coolant is already premixed with distilled water, 50%/50%. If you have 3 quarts of water in the engine left over, and add 6 quarts of 50%/50% coolant, you will end up with 33% coolant and 67% water which is insufficient protection in cold winter areas like Illinois.
Isn't it published some place that your NOT suppose to flush the Prius system , just drain and refill? I thought I remeber reading that someplace.
I think Galaxee listed that in her post on what you need and don't - there really isn't any need to flush unless you have let the coolant go too long and have corrosion products in the system. That should not be true if you follow the recommended change interval.
From Galaxee's recommendations: 4. engine and inverter fluid drain/fill is OK, but NO flushes. it's not even possible on the inverter and the engine is difficult but not impossible, however NOT recommended as it can cause serious damage to the electric water pump and switching valves. you do not need the drain/fill until your car hits 100k. if the coolant is still nice and pink, don't do it then either. again, the coolant is said to go 100k. while you're not going to do any wrong by changing it early, again it is expensive like the trans fluid. possible complications include more tech error- bleeding these systems is a PITA and getting all the air out is hard. an incomplete fill, use of the wrong coolant, can damage your car. Sounds like the dealer caused the damage and paid to fix it.
What did they do, put silicate-based "green stuff" in and precipitate out all the solids? See the references in my coolant study for lots of info on the many, many things they could have done wrong. . Note that I haven't actually done my engine coolant yet... likely on the agenda for spring. . _H*
Good point. I checked the coolant at the radiator and the inverter with a simple floating ball tester. It indicates maximum protection for both. However, coolant level is just below the "Low" mark on the engine coolant reservoir with engine cold - should I go back and have them top it up? I also noticed a silver dollar size puddle of coolant on the garage floor under the inverter today.
Yes, you should definitely have the reservoir topped off. This is showing you that some air was trapped in the system and finally worked its way out, so the fluid level dropped. In addition, pls point out that you see this coolant leak under the inverter. Maybe the tech did not properly tighten the transaxle drain plug.
Thanks to all for taking the time to reply and for the valuable info. It shows I haven't become all that familiar with Prius Chat yet, but I can see it pays to be informed. I'm not sure what the service tech did to "flush" the coolant loop, but I will ask the question when I go back for a top up - wish me luck.
Toyota service tech topped off the reservoir and claimed he saw no leak (neither did I after that appointment) 20k miles later all is well. No runaways either, but I run by quite a few gas stations Thanks for your valuable inputs. Tom