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Engine Rear Main Oil Leaking?

Discussion in 'Generation 1 Prius Discussion' started by RW5207, Nov 16, 2014.

  1. RW5207

    RW5207 Junior Member

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    My wife noticed a puddle of oil on the garage floor when I left the other night and unfortunately, it is coming from my 2002 Prius. I jacked it up today and found the oil was NOT dripping down from the side of the engine, but appeared to be coming out of the hole in the casting between the engine and the transmission. This looks to me like a leak on the main seal on the rear of the engine.

    Anyone ever have this happen? I'm capable of fixing something like this, but I'm thinking it may not be worth my time at this point in my life.

    Thanks for your help and comments!

    WP_20141116_09_36_37_Pro.jpg

    Russ
     
    #1 RW5207, Nov 16, 2014
  2. Britprius

    Britprius Senior Member

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    That does very much look like engine oil. Transmission oil the only other likely source is red in color. You could try an oil additive that softens the seals to help prevent leaks, worth a try on a purely cost basis. The engine would need to be removed to replace the seal and unless the leak is real bad not worth the cost or hassle.
    If an additive does not work a drip tray under the car and a regular oil level check would be the most cost effective way of dealing with the situation.
    Replacing the PCV valve may cure the leak and is another cheap option to try.

    John (Britprius)
     
    #2 Britprius, Nov 16, 2014
    Last edited: Nov 16, 2014
  3. bwilson4web

    bwilson4web BMW i3 and Model 3

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    The risk is the torque limiter, a clutch plate, clamped to the flywheel. When it starts to go at high-power, there is no alternative.

    Bob Wilson
     
    #3 bwilson4web, Nov 16, 2014
  4. RW5207

    RW5207 Junior Member

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    Thanks, guys. It's definitely engine oil...no doubt about that.

    From the looks of it, I'm guessing the transmission would have to be removed to get to the seal. The last FWD transmission I removed was a manual on a Chevette that needed a new clutch (now I'm dating myself). Still have the clutch pilot tool in one of my toolboxes. :D

    I like the idea of replacing the PCV valve, as too much "positive crankcase pressure" might be the root cause when I was recently zipping down the highway at 80-90 mph. I'll do that, change the oil, and put a disposable drip pan (i.e. pizza box) underneath it to keep track of progress.

    Worst case, I'll pull the transmission to replace a $20 seal...next spring.

    Russ
     
    #4 RW5207, Nov 17, 2014
  5. popptj2001

    popptj2001 Member

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    Just curious, did replacing the PCV valve help any?
     
    #5 popptj2001, Apr 1, 2015
  6. ChapmanF

    ChapmanF Senior Member

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    If you do ultimately go after the seal, be prepared to apply some cleverness. I've worked on older engines where the rear main seal lives in a carrier ... you can unbolt the carrier from the block, change the seal on a workbench, and bolt the carrier back into place.

    In your 1NZ-FXE, there's no carrier, just a round bore cut half into the block and half into the upper oil pan casting. You pull the old seal out and press the new one straight in, which means if you're working in situ on the car, you need the transaxle far enough out of the way to give yourself room for that.

    -Chap
     
    #6 ChapmanF, Apr 1, 2015
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