100K maintenance fun

Hey Hobbit, thanks for the interesting and entertaining read. I got a question for you. Since it seems such a PIA to monitor the inverter temp., is there an easier way to just rig up an idiot light to let you know if the inverter pump fails while your driving?

 

Great info. Hobbit! Good reference materials for any maintenance/repairs in the future (hopefully the not so near future). Thanks!

 

Hobbit

As usual a good writeup

Brake fluid in the Prius does appear to stay in good shape far longer than in conventional vehicles. I'm not really sure why.

I do know that with most conventional vehicles with translucent fluid reservoirs, after 2-3 years the fluid will turn from a light honey color to a very dark color. Some even turn black

I did a brake fluid flush on my FJ this summer, as I noticed the fluid was starting to become dark. This is after only 2 years and 25,000 km! For some reason, the rear disk brake calipers had a lot of fine suspended trash in the fluid

Like the Prius, the FJ has electric assist brakes. I carefully instructed the helper to only keep light pedal pressure, ign on, while bleeding the rear brakes. Like the Prius, the pedal does NOT sink when bleeding the rear brakes

The front brakes feel more "normal." After I was done, the pedal felt a lot firmer, with a bit better response. The right rear caliper did burp a bit of air before fluid came out the tube

 

Awesome info site there Hobbit! Thanks for taking the time to provide for us.

 

Jayman, do you think that Prius brake fluid experiences smaller temperature extremes than in 'friction-only' vehicles? This would probably limit the chemical interaction rate between fliud and brake system components, but I don't see how it could reduce water absorption as such.

Will Hobbit's garage schedule appointments for Prius work?

 

ahh, finally! DH has been arguing for years that brake fluid doesn't need to be flushed all the damn time in these cars.

 

Hi Hobbit,

I especially enjoyed learning about headlight removal without first removing the entire front bumper cover, and your experience testing the used brake fluid. Thanks for sharing that very useful knowledge with forum members.

It was also interesting to read about your use of the black plastic fasteners (that are used to secure the plastic fender liners) in other areas of the car. I also came to that realization yesterday when I had to replace the two plastic clips that hold the two black plastic cowl pieces. The fender liner fasteners work well in that application and are easy to remove.

I wanted to comment on the engine water pump seepage that you've noticed and your policy to keep the serpentine belt relatively loose. I realize you live in the Northeast and are a hypermiler, thus I assume that your engine doesn't see 5,000 rpm often while ambient temps reach 90+ degrees F at highest. That may be why your loose serpentine belt works OK.

The manufacturer's spec on the serpentine belt tension has to take into account all reasonable use scenarios. My car routinely sees 75+ mph speeds (as that is the speed limit on Western rural highways) and ambient temps can get up to 120+ degrees F. I definitely do not want the belt to slip when the engine is revving up under those conditions.

MSRP for the pump is $92 and I can buy it for $70 plus shipping.
http://www.trademotion.com/partlocator/index.cfm?action=getLocator&siteid=213747&chapter=APM820&appSectionid=8&groupid=62105&make=34&model=Prius&year=2004&catalogid=1

Since this pump is so inexpensive and is relatively easy to replace, what is the motivation to eke out the last bits of service life?

In my case, as soon as I see the slightest hint of pink coolant weeping out, I will place an order and replace the pump the next weekend. I don't want to have an unscheduled failure literally in the middle of nowhere...

I recognize that reasonable people can have different opinions on this, depending upon their particular situation and circumstances, and tolerance for an unscheduled failure. This is like some owners who wait until their 12V battery fails before installing a replacement, while others (like me) will install a replacement based upon years in service.

 

The water pump on my 07 with 19,000 miles on it shows some pink crust in the area of the weep hole, but doesn't show signs of slinging any coolant from the pulley. The level in the overflow tank is still above the low mark and I have never had to add any fluid yet.

Perhaps I should mention it to the dealer's service guy before Feburary when the car will be 3 years old.

Hobbit, what are your thoughts on this?

 

Meh, what's the worst that could happen?

Asides from a trip to your very own ER department?

I've been thinking about this for several years now, and its the only thing that makes sense. Especially when you consider that my FJ also uses electric assist power brakes, so many parts are in common and/or work in a similar manner

When I finally had the Prius brake fluid flushed out, it was still in pretty good condition. After only 2 years, the fluid in my FJ was almost black, with a LOT of fine suspended stuff, like sediment.

 

Plus the neighbors might say... Hey who's that guy in the green dress with the paper hat and gloves doing to that car? and why does he have a big flood light shinning on it when it's daylight?:gossip:

 

That is certainly true of industrial pumps with ceramic seals, water cooled and lubricated. If for any reason the plant water system has low pressure, or a clog develops in the seal drain pipe, the seal will quickly destroy itself

 

I do not see PCV valve replacement and I thought that would complete the 100k mile maintenance. Maybe it should be replaced before 100k miles (suggested by galaxee?) but I have yet to replace mine. I plan to do it with the spark plugs at 120k.

 

In addition to the copper color-strips there's more than one way to measure brake fluid water content. Jerry Whitmarsh in UK bought a water-tester and found his prius fluid to be much 'drier' that that of similar age friction only cars. Meanwhile, if Toyota has managed to reduce copper transfer to the fluid that's great also.

Brake fluid doensn't change volume much with temperature. The only mechanism I can imagine for more water entrainment into conventional brake fluid is pressure changes in the captive air in the reservoir following a fluid thermal cycle.

The crudest brake fluid metric of all is 'how does it look?". Any Prius driver can look at their underhood reservoir, and calibrate their eyes at any new-car lot. It is my impression that Prius is unique in having straw-color original looking fluid no matter odometer etc.

The original Vancouver Prius taxi service records are online somewhere. Andy got new brake fluid about every 30,000 km (?) - I always suspected he was getting ripped off.

 

hobbit, we wrote a little something up if you want to link to it:
http://priuschat.com/forums/knowledge-base-articles-discussion/56852-pcv-replacement-how-photos.html