How important is getting the serpentine belt changed?

Discussion in 'Gen 2 Prius Main Forum' started by desertrider2215, Jun 18, 2010.

  1. desertrider2215

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    almost 130,000 miles, and I haven't changed it yet. around what time are you supposed to change it, and what happens if snaps while you are driving?
     
  2. edthefox5

    edthefox5 Senior Member

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    What happens is the water pump and the alternator stop spinning. Its a race to see which dies first the battery or the engine from overheating. It would immed. throw a CEL as the battery would no longer be receiving a charge.

    But liike most Prius drivers I see post here you prob would continue driving until the engine overheats. Most people do not realize that the Prius unlike alot of other modern cars when it throws a CEL it ain't kidding.
    When you get a CEL unless you know exactly what its unhappy about pull it over and flatbed it home.

    At that mileage in addtion to the serp you are due for:

    Sparkplugs (way way overdue)
    CVT trans fluid replacement ( wwo)
    Complete engine coolant flush (if you haven't kept after the coolant your probably looking at a new water pump too)

    Complete Inverter coolant flush
    Complete brake check---- pads and rotors for sure up front
    Struts
    And most would think about coolant pump replacement too
     
  3. V8Cobrakid

    V8Cobrakid Green Handyman

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    your water pump will stop functioning... that's all.. in turn that will make your ICE overheat.

    what's the other thing?... alternator?... (<--- not on a prius)
    a prius does not have an alternator...

    everything else mentioned, should be checked.

    your brakes should be checked... your rotors are probably fine. your brakes might be perfectly fine too. (some on here go longer with plenty of brake life left)
     
  4. V8Cobrakid

    V8Cobrakid Green Handyman

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    btw... spark plugs are supposed to last till 150k miles. iridium tipped (or something fancy... i read up all about them about a year ago.. you Can replace them... i'd at least crack them loose to make sure they are not welded in there.. ok.. not welded.. but a pain to get out since they are probably dry... (they ship with anti-seize lube)

    spark plugs and brakes are the cheapest to replace.. you might as well... i'm simply saying they probably have a little life left.
     
  5. hobbit

    hobbit Senior Member

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    And forget this "complete flush" nonsense. Just drain and refill.
    Read the research at the end of my 100K maint page on coolants.
    What are you going to flush *with*? One guess... and do you want
    puddles of that ion-laced, uncontrolled substance kicking around
    in your new coolant as opposed to the simple presence of a little
    older coolant that mixes right in with the new stuff's anti-corrosion
    protection?
    .
    _H*
     
  6. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I would change the belt when it becomes glossy, which is around 70K miles. See my post #18 here if you wish to DIY: http://priuschat.com/forums/gen-ii-...45143-service-schedule-serpentine-belt-2.html

    If the belt snaps, then the engine water pump will no longer spin and the engine will overheat. If you don't immediately stop, the engine will be destroyed.

    Considering that the belt is pretty inexpensive and you won't have any advance warning of a failure, I do not recommend deferring its preventive replacement any longer. While you are at it, I recommend that you catch up with the 100K and 120K mile scheduled maintenance items if they have not yet been done.
     
  7. uart

    uart Senior Member

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    In a regular car (with alternator) you get usually an immediate warning light if the fan belt goes. Do you get any warning in the Prius or is an engine light from overheating your first and only warning. Just wondering?
     
  8. jayman

    jayman Senior Member

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    With the older green stuff, which you mixed with tap water, the cooling system would often scale up unless you did the drain, flush, refill every 2 years

    The new organic acid coolants, which come premixed, offer MUCH longer protection

    I agree, just do a drain and refill

    With the old green stuff, leaving behind the descaling chemicals often caused you just as much grief as the old coolant. The stuff foams like crazy when hot.

    The only solution was to rinse the cooling system with a LOT of water. If the tap water is hard water, you were then all but guaranteed to have more scale in a year or so.

    Even if the tap water was "soft" water, municipal tap water has a lot of chlorine in it. That also tends to react with the cooling system, creating deposits.

    Lets not forget all that water left behind in the cooling system. All most shops do is open the drain valve in the rad. A substantial amount of coolant can be left behind in the lower hose, as it has a low spot in it.

    So you then refill with what you assume is correctly-mixed 50/50, but due to the extra water left behind in the block, heater core, and hoses, you're actually running 30% coolant and 70% water.

    Which makes the scale problem that much worse

    No, do NOT do a "flush"
     
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I would expect the master warning light to turn on, and a red engine overheating icon to appear in the MFD, once the engine has reached the point where it is overheated. Thus, the owner would need to stop the car immediately at that point, or risk damaging the engine.
     
  10. David Beale

    David Beale Senior Member

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    Uh, why has nobody recommended -LOOKING- at the belt. You can usually tell if it is about to retire badly. Cracks etc. It's in the manuals.

    And yes, they don't last indefinitely. Replace when inspection shows it's necessary, as per the manuals.

    Or buy a GIII, which has no belt. Problem solved. ;)
     
  11. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Because you are not going to see much while the belt is installed in the car. If you want to see cracks you have to remove the belt and bend it so that the ribs are exposed. Then you'll see plenty of cracks if the belt has been in service for 60K miles or more.
     
  12. adamace1

    adamace1 Senior Member

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    What is this "belt" you guys speak of? Are you guys saying your water pump is powered by the gas motor? I think i can remember back in the day my cars did that. :)
     
  13. edthefox5

    edthefox5 Senior Member

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    Altenator?....yeah thats what happens when you post at 4:00 Am on pain pills. Plus my Haynes keeps referring to the "alternator" specifically for the serp belt. Sorrry about that.

    I specified "flush" because I want the OP to go to the dealer and get there car straightened out and maybe not attempt a home tune. The dealer says "flush" but I imagine does no such thing.
    But the dealer does have the vac and hopefully will use it so the OP gets some new coolant installed correctly and not have the gurgle like so many posters here.

    I've never "flushed" a car in my life.

    But I do take out the thermostat...Put the thermo housing back on sans thermostat and fill up the rad with tap water. Run the motor for a minute. Dump the rad again. I keep doing this till I see no color out of the rad. It only takes a minute or two to circulate the water/coolant without the thermostat itself installed and you do not need to wait for a motor heat up interval. After I'm satisfied its pretty clean I let the rad drain for around 5 mintes and then I pour 100% coolant into the thermo hole until its to the top. I then install a new thermostat. I then fill up the rad with new coolant and distilled water.

    Some cars thermostat housing's will nto seal properly without the thermostat itself installed as there's a lip/groove gasket thing there so I usually just rip out/destroy the old thermost's center flap assy by ripping out the center pellet flap leaving just the rim. Its easy its just tin. I bolt that rim in and flush away. When I'm done I install a
    new thermostat I have already bought. A new thermostat is $ 5. and cheap insurance. Always replace that too. Takes like 15 minutes and you can get it really clean this way.

    Never ever have had vapor lock doing this.

    But!!.. I have never done this on the Prius yet either.

    I use this stuff linked below too. It's a very good anti corrosive product. Been using it for years. Much better than the white water pump lube. I put a bottle of this in the rad and the inverter coolant tank the day I brought my car home. I just used a turkey baster to suck the fluid out to make room for the WW. Very good product. I once owned a Nissan for 15 years and used this product exclusively in the radiator and the rad looked brand new the day I sold the car.
    I don't know about the water "wetting' claims but its a very good anti-corrosive water product. I do know that I have been in Florida since 1980 and have never had a car overheat on me either using this stuff.

    Red Line Synthetic Oil - Water Wetter® Coolant Additives - Water Wetter®
     
  14. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Yes - well, wait for some miles to be logged on the 2010 population, and we'll see how reliable the electric engine coolant pump is... :eek:
     
  15. adamace1

    adamace1 Senior Member

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    Ok.
    Doesnt your car have a belt drivin water pump for the ICE and then a electric one for the inverter? I thought my car has two electric water pumps. I think they will be fine. I have seen alot of reports of the belt drivin ones leaking and getting replaced on the older models. I can't see how the new design will be more trouble some. If made right an electric motor is very long lasting.
     
  16. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Yes, the electric inverter coolant pump has been a trouble spot with Classic and 2G Prius.

    With a traditional mechanical engine coolant pump, it is relatively easy to see if the serpentine belt needs to be replaced. Usually the water pump will weep coolant before the bearing fails, so if you as the owner are paying attention you'll get some warning before the pump actually fails.

    With an electric pump, it's not so obvious that the pump is in distress. Typically the owner has no idea that a problem exists unless an overheat warning light comes on.
     
  17. desertrider2215

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    ahhh, the classic water pump(s). had both replaced in the early 100s. upwards of $300 a piece :eek:
     
  18. timtim2008

    timtim2008 Member

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    yeah, the belts only $19 @ autozone
     
  19. richard schumacher

    richard schumacher shortbus driver

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    The motor on the 2G was fine, but the single-point pump bearing was inadequate.
     
  20. Mike Dimmick

    Mike Dimmick Active Member

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    North America 2nd-generation has four water pumps. One electric that runs the inverter coolant loop. One mechanical that runs the engine coolant loop when the engine is running. Another electric that pumps hot coolant through the heater to warm the cabin, when the engine's off. And one to pump hot coolant to/from the coolant heat storage tank (thermos), when the engine has just stopped/is about to start.

    My car, not having the thermos, only has three.

    I haven't seen many reports of issues with the two electric coolant pumps in the engine loop, but the motorized valve that directs coolant flow to/from the thermos seems to be a common failure.

    The third-generation car fixes this idiocy and drops the mechanical pump, and the second pump for the thermos, because the thermos has gone. In place of it, the coolant loop runs down to the exhaust to pick up heat to speed up engine (and cabin) warm-up. I believe there are still valves to bypass this, though.
     
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