Urgent timing help needed.

Discussion in 'Gen 2 Prius Main Forum' started by Prius92, Nov 16, 2024.

  1. Prius92

    Prius92 Active Member

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    I poke around in my phone since I always take a ton of pics.
    Here's another pic of the engine timing.
    It should be between the link rivets, yes?
    [​IMG]
     
  2. ChapmanF

    ChapmanF Senior Member

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    I think I'm still with mr_guy_mann. Here's an attempt to deal with the perspective by fitting similar ellipses to the end of the crank and the ID of the sprocket, then adding a line through the dot from the center of the ellipse.

    Kind of a crude method, but I do think I'm more convinced that tooth ends up between the colored plate and the next one up, rather than between the two pins of the colored plate.

    [​IMG]
     

    Attached Files:

  3. Prius92

    Prius92 Active Member

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    I took the timing cover off and the chain.
    I did notice the VVT-i timing gear was not lined back up right, so I'm thinking it might be bad as well.

    Anything to look for on the chain itself?
     
  4. ChapmanF

    ChapmanF Senior Member

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    Can you reassemble it all and get a good photo clearly showing the crank dot and tooth square in the middle of its colored link, with the top colored links squarely on the cam marks?

    What do you expect to see for the VVT-i gear "lined back up right"?

    It has a certain range of motion with respect to its camshaft, though it may also have a spring pin that should latch it at the most-retarded position (toothed part turned most clockwise) if you get it to that position.

    The exact phase of the VVT-i gear on the camshaft isn't really critical for installing the chain, because you're lining the colored chain link up with the mark on the toothed part.
     
  5. mr_guy_mann

    mr_guy_mann Senior Member

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    What are you using to measure the cam and crank signals?

    A scope with the proper settings will display the actual waveforms. Both sensors are "variable reluctance" type that generate AC voltage pulses as the shaft trigger "wheels" pass close.

    Here's what both sensor signals look like on a Gen2. Blue is the cam, red is the crank. In particular, the ECM is looking at the position relation of the cam sensor peaks vs the "signature gap" of the crank sensor.

    PS, I would believe the "basic" voltage readings on your device (scope?). 5V "peak to peak voltage" for the cam is about what I show, and 16V ppv for the crank is slightly higher than mine but "ok". I just think that you have too high of a time base to really see things. Try switching to less time per screen (smaller time base).

    Here I have 125 milliseconds for the entire screen, which is just over 2 crankshaft revolutions at idle. (You need a very powerful scope to capture enough data to be useful at your 1 second per division - 12 sec per screen).

    If there's too much time on the screen (or not enough sample points for the speed of the signal), then you end up with irregular jagged spikes instead of a smooth pattern.

    tapatalk_1732245034430.jpeg

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    #25 mr_guy_mann, Nov 21, 2024
    Last edited: Nov 21, 2024
  6. mr_guy_mann

    mr_guy_mann Senior Member

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    Valve spring pressure on the camshaft lobes can push things around. Just follow the service manual procedure and put the chain back on.

    Then recheck alignment, get a good pic of the crank sprocket. Put the camera down low inline with the crankshaft.

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  7. Prius92

    Prius92 Active Member

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    Any good recommendations for a timing cover sealant?
     
  8. mr_guy_mann

    mr_guy_mann Senior Member

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    My favorite is HondaBond (RTV). Good balance of working time vs oil resistance. Gotta get the sealing surfaces completely clean and dry.

    Toyota's Form In Place Gasket (RTV) is also good.

    Most (oil resistant) "ultra" series RTV can work. I prefer the OE stuff for "known good" performance.

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  9. Prius92

    Prius92 Active Member

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    HondaBond 4 or HT?

    How many oz will I need?

    Also, prob a dumb question, but to keep from missing the mark and sliding some off due to limited working room, can I just put it on the block instead of the cover?

    Timing chain looks fine. While it came from DNJ, I compared the stamping on the links and it appears to be made by Cloyes.
     
  10. highmilesgarage

    highmilesgarage Active Member

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  11. highmilesgarage

    highmilesgarage Active Member

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    1 pack is plenty enough, I don't think you could buy any smaller than the standard size/pack. I don't think it will be easier to apply the RTV on the engine side while in place. Doesn't matter which side when the engine is out of the car.
     
  12. mr_guy_mann

    mr_guy_mann Senior Member

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    Cloyes is now just "a name". They were bought out a few years ago and quality has been reported as very spotty. I wouldn't use them if I had any other "reasonable" choice.

    I always get the Hondabond HT (1.9oz.). Since the open tube will sit around until (when - if) I use it for the next job, I waste less with the smaller size. It's still plenty for a timing cover.

    Haven't used the "4".

    Sure, goop up the engine if that's easier for you. It's a toss up. Easier to reach - apply on the cover, but less likely to scrape it off if applied to the block.

    Before sealing it up I would "dry fit" the cover and crank pulley. Then rotate the engine the engine a few times and recheck cam timing before using sealant.

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    #32 mr_guy_mann, Nov 24, 2024
    Last edited: Nov 24, 2024
  13. Prius92

    Prius92 Active Member

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    [​IMG]

    Is this better?
     
  14. ChapmanF

    ChapmanF Senior Member

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    Now that, I like.

    If I remember right, the 1NZ-FXE crank position sensor sticks in at about 8 o'clock in this picture. The signature gap in the position teeth is about 3 o'clock here, so if this is TDC then the signature gap in a scope trace should be around 120° ATDC. Anybody happen to know if that's right?
     
    #34 ChapmanF, Nov 27, 2024
    Last edited: Nov 27, 2024
  15. Prius92

    Prius92 Active Member

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    Cleaning off the timing cover is a giant pain in the rear. No chemical seems to melt the RTV. I tried 5 different ones.
    Not to mention digging it out of all the little nooks and crannies.
    If I had the money I would have just spent $87 shipped on a new cover which comes with the pump.

    Which leads me to another irritation.
    You have to clean the oil pump completely out. Otherwise oil will drip down and potentially contaminate the RTV when sealing it.
    You can't take the screws out of the pump without messing them up, and no one sells just the screws.

    A new pump (with the screws) costs almost the same as a whole timing cover with the pump included (which makes no sense)

    So you have to run solvent through the holes to clean out as much oil and let the rest evaporate.

    Also while looking online, the 2012-2020 1.6L Kia/Hyundai engine has a very similar timing chain cover.
    [​IMG]
     
  16. mr_guy_mann

    mr_guy_mann Senior Member

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    I push some Vaseline into the oil pickup port then rotate the pump to "suck" it through. Do that enough and it'll seal the pump. "No" (less) drips and it's primed to pump immediately.

    I do not like having a dry pump - can take too long to move oil on initial startup.

    You can try using some gasoline to soak the RTV, that used to soften & swell it. (IDK if that still works on modern "ultra" type sealers) Mostly I just use a carbide scraper and patience.

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  17. Prius92

    Prius92 Active Member

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    I am so mad.
    I wanted to reseal the timing cover so it could sit over the weekend.
    The Ultra Grey I bought must of been old, it would not come out of the nozzle even with it unscrewed and the foil seal punctured.
    Ended up coming out a hole in the side all over my nice work jacket.
    I kept it in the house the entire time before using it so it wouldn't get cold.
     
  18. Prius92

    Prius92 Active Member

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    Got the timing cover resealed and put back on.
    [​IMG]


    [​IMG]


    I noticed the crankshaft seal does not close around the crankshaft perfectly.

    I even went as far as replacing the seal and it still does it.

    When I had the seal out, I double checked the crankshaft itself and the hole in the timing cover, and didn't see anything out of sorts.

    I cut the old seal in half, and saw that a lot of the sealing actually occurs farther inside, so hopefully it doesn't leak.
    Luckily you can swap it out without having to remove the timing cover.

    [​IMG]



    As far as RTV, I talked to a lot of engine builders and they all said Permatex Right Stuff Black 90 Minute

    The black RTV is better suited for oil resistance than the grey. Considering around 85% of the mating surface is in contact with oil, it makes more sense to use the black.

    Now the grey is better suited for coolant, BUT if my understanding is correct, the pump is sucking coolant towards it, so in theory you are trying to prevent oil from getting into the pump area, not coolant from getting into the engine itself.

    If you really wanted to be "sure", I suppose you could use the Permatex specific water pump sealant in that area, but every engine builder I talked to says the black "Right Stuff" is some of the best RTV.

    Now if you went "by the book", the Toyota or Threebond RTV for the water pump area runs $80 a tube.

    Also the reason a lot of "old heads" prefer the black RTV is because when "The Right Stuff" came out, it was ONLY available in black.

    I'll talk to Permatex sometime, but I believe the grey and black have roughly the same coolant resistance, the grey is better for "high torque applications".

    Well considering most of the timing cover bolts are only torqued to 8 ft-lbs, I don't consider it to be a "high torque application".

    Black is also slightly more flexible, and considering the low torque of the timing cover bolts, it would make more sense to use a more flexible RTV.
     
  19. highmilesgarage

    highmilesgarage Active Member

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    where did you get that $80 price? last time I bought the Toyota FIPG at the dealership it was $15, recently it's $25 (or $20 can't remember) at the same dealership. Best thing about the Toyota FIPG is that it's anaerobic which means that you can apply it and don't worry about curing too fast until it's sealed/tightened. I've been using this for a long time even with my BMWs and Benz (oil leakers) without any issues. By the time you're done assembling it's already cured (2 hrs)

    I don't see you replace the o-rings (there are 2) or inspect them, they are sources of leaks under the timing cover.

    Face Sealing - Anaerobic or Silicone Sealant - Tech Bulletin
     
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  20. Prius92

    Prius92 Active Member

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    I did replace the o-rings.

    There are two types of sealant used per the manual.

    The water pump area uses Toyota Adhesive 1324, the other areas use Toyota FIPG or "Genuine Seal Packing - Black"

    Oddly, the adhesive is the same as threadlocker.