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TR engine knock

Discussion in 'Boxers/TR/M' started by tamburini44, Jun 6, 2019.

  1. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
    Hey all,

    I think my TR knocked itself out, literally.

    We're having new doors installed in one of our garages so I was moving the TR into our other garage,
    i.e., low speed and RPM's.

    There was a sudden fast knocking noise, knock knock knock 3 times, somewhat like the kind you'd get if you slowly push the stick shift towards a gear without pressing the clutch pedal. Then the engine shut down, I remember seeing the battery light.

    I restarted it and immediately there was a very loud clack clack racket.
    Pushed it a touch higher than idle and the tempo of the noise increased, so it's RPM dependent, then shut it off.


    Car's had a major about a year ago, just before I bought it, new belts, clutch, rebuilt water pump, etc, 10w50 synthetic oil, did about 200 miles since, total of 39k currently, correct oil level, looks clean on the dipstick.
    Never had it passed 5k RPM, never passed 3k when cold.

    No strange noises before this.

    Based on how it sounds, I'm thinking rod knock.
    Surprised that it would progress from nothing to full on knocking at idle.

    I pulled the fuel pumps relays and cranked it once and could hear a repetitive thud.
    I got a recording of it but apparently I can't upload audio or video files.

    I'm having a mechanic come by in a few days but any advice and ideas are welcome.

    Many thanks
     
  2. Veedub00

    Veedub00 F1 Rookie
    Silver Subscribed Owner

    Jun 30, 2006
    3,453
    Troy, Michigan
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    James
    alternator belt? A/C belt?
     
  3. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
    I was under the car yesterday, didn't see anything out of order.
    Oil pan has lots of sealer though. Wouldn't surprise me to find it inside also.
     
  4. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
  5. Zeff

    Zeff Formula Junior

    Oct 8, 2018
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    Cupertino, Ca
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    Ryan
    johnk... likes this.
  6. vincenzo

    vincenzo Formula 3
    Silver Subscribed

    Nov 2, 2003
    2,424
    As a kid, I was diagnosing a knock. Pulling sequential plug wires to see if it was a rod or main.

    The bearing spun during the process and seized the engine..... HARD.

    The spun bearing did significant damage to the crank, but was still repairable.

    Running the engine with a bearing knock is HIGHLY risky. Use care.
     
    Natkingcolebasket69 and Zeff like this.
  7. jjtjr

    jjtjr Formula Junior

    Aug 29, 2016
    328
    Vermont
    Full Name:
    john truskowski
    ^^ I would first remove the accessory drive belts and spin all pulleys by hand to rule out anything there. And as post 6 says running an engine with a spun bearing even at idle is risky. Hope for the best!
     
  8. DonB

    DonB Karting
    Rossa Subscribed

    Nov 11, 2003
    240
    Florida
    Full Name:
    Don Bartz
    Had a friend with a TR. Concours car, beautiful, 10K miles. Started the car at a Concours, got the same noise, and come to find out it broke a valve, which went into the cylinder, and $10K later everything was OK.

    Certainly hope that's not the case with yours! It will be interesting to find out what it is..be sure and let us know.
     
  9. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
    Thanks for the suggestions. I'm not going to start it.
    I was going to check the compression, but I'll see what the mechanic says before deciding how to proceed.

    One thing I forgot to mention, the oil pressure was a bit over the quarter mark, when I restarted after it had shut off.
     
  10. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
    Yeah, at this point I hope it's a valve.
     
    Natkingcolebasket69 likes this.
  11. ago car nut

    ago car nut F1 Rookie
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    Aug 29, 2008
    4,241
    Madison Ohio
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    David A.
    A knock with good oil pressure doesn't mean all is well with the bearings!
     
    turbo-joe likes this.
  12. DonB

    DonB Karting
    Rossa Subscribed

    Nov 11, 2003
    240
    Florida
    Full Name:
    Don Bartz
    You could scope each cylinder with a video viewer (available at Home Depot) . That way you could at least verify that a valve didn't drop, and it wouldn't require starting the car.
     
  13. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
  14. JohnMH

    JohnMH Formula 3
    Silver Subscribed

    Jan 28, 2004
    1,010
    Dubai, UAE
    The black grille (removed in photo) is held in by screws which thread into those metal tabs.

    The red horizontal metal area which the black grille bolts to is part of the bodywork and is not removable as far as I am aware.

    Were it my car, I would remove the plugs and inspect each electrode for damage, then check each cylinder with a cheap borescope, and then drain the oil and look for metal. If all that checks out, I would turn it over by hand and check that the timing marks still line up on all 4 cams (looking at the back of the pulley covers without removing anything and the flywheel timing mark without removing anything).

    If it still seems ok, I would pull the cam covers and look there next.

    Is it a metal on mental knock sound?

    Good luck...
     
  15. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
    Thanks for the tips.

    It doesn't look removable, but I saw a couple of posts where the red part was removed, one from someone changing the alternator and another removing the engine.

    The initial sound was like a gear grinding in slow motion.
    After I restarted the sound was bad, loud, metal on metal. Seemed to be coming from the top of the engine,
    but, that was from within the car.
     
  16. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
    It's bank 1-6. Can't see anything on 3-4 but the rest got marks. Photos coming up.
     
  17. tamburini44

    tamburini44 Karting

    Jun 6, 2019
    82
    So the belt slipped on 1-6? The timing belt cover on that bank is slightly deformed.
    As mentioned the major with belts was about 1 year / 200 miles ago, at least according to the paperwork.



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  18. Steve Magnusson

    Steve Magnusson F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    18,312
    Texas
    Full Name:
    Steve Magnusson
    There are "approximate" cam timing marks on the timing belt rear covers (the distorted flat cover in your photo) and the cams -- not something that you could use for even +/- 5 degrees accuracy, but can be used to confirm/deny if a big cam shift has occurred (a shift large enough to cause valve-to-piston contact).

    A major service being that "fresh" (without much subsequent use to prove it is "sorted") can be a bit of a risk IMO.
     

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