1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

Noise In The Front Of The Engine

Discussion in 'Flat Fender Tech' started by ardan, Feb 22, 2020.

  1. Feb 22, 2020
    ardan

    ardan Member

    West Tennessee
    Joined:
    Mar 19, 2019
    Messages:
    52
    HI Guys,

    I have had a very bad day. After 700 hours over the last year I was ready to test start my 1950 cj3a. I had ran it earlier in the restore/rebuild and it ran great, I even drove it for several miles and the engine ran great. After I rebuilded the entire jeep (except Still working on the hood and windshield) I was ready to test it this morning. It started and ran great, for about 10 minutes. When the temperature reached about 140 there was a horrible screeching sound from the front of the engine. (L134 Go Devil). Hoping it was the water pump or the alternator I removed the fan belt and it restarted it, the noise came again at about 140.

    I am looking for ideas, Could this sound be caused by oil not getting to the camshaft gear, oil pressure is good but I guess that the little oil squirter could be clogged. Or is that the sound of the main bearing going out or could it be something else.

    I am really regretting ever starting this project. Any advise will be greatly appreciated.
     
  2. Feb 22, 2020
    PeteL

    PeteL If it wasn't for physics, and law enforcement... 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Hills of NH
    Joined:
    Aug 3, 2003
    Messages:
    9,754
    Try a stethoscope against the different parts of the engine, locate the exact source point.

    A wooden dowel or a long screwdriver pressed against your ear will work. Be careful of moving parts.

    Are you sure it's at the front, not the starter or clutch/throwout areas? Did you pre-lube all the bearing surfaces and prime the oil pump when you did the rebuild?
     
    Last edited: Feb 22, 2020
  3. Feb 22, 2020
    ardan

    ardan Member

    West Tennessee
    Joined:
    Mar 19, 2019
    Messages:
    52
    Hi,

    I tried a wooden dowel against the timer cover, starter, throw out bearing and the sound sounds like is louder in on the timer cover. But I must admit I am not good at that and will get my brother over for a second opinion.
    I did not prime the oil pump, I will look into that also. Oil pressure is reading 35 at idle.

    I will post again after I get my brother to listen to it.
     
  4. Feb 22, 2020
    jpflat2a

    jpflat2a what's that noise?

    Hermosa, SD
    Joined:
    Jul 30, 2003
    Messages:
    8,513
    video of the noise ?
    Can't see a connection to 140* and oiling problem.
     
  5. Feb 22, 2020
    ardan

    ardan Member

    West Tennessee
    Joined:
    Mar 19, 2019
    Messages:
    52
    HI Guys,

    Just posted a video of the engine starting and running, It doesn't have an alternator or a fan belt on it. At about 2:25 in is when the noise starts.



    Any ideas would be greatly appreciated.

    Thanks Ken
     
  6. Feb 22, 2020
    duffer

    duffer Rodent Power

    Bozeman, MT
    Joined:
    Sep 17, 2009
    Messages:
    4,460
    Is all that runout in the crank pulley or is the crank snout bent? And is it rubbing on the cover? I don't think any of the rod or main bearings are the source of this.
     
    jpflat2a likes this.
  7. Feb 22, 2020
    ardan

    ardan Member

    West Tennessee
    Joined:
    Mar 19, 2019
    Messages:
    52
    The Crank Pulley was bend when I removed it, I was getting ready to order a new one but was trying to go ahead and test it since everything else is ready. The crank snout seems to be fine. The pulley is not rubbing on the cover as there is a visible gap all the way around.

    I may pull the pulley and try to run it that way just to make sure. The thing that is really puzzling is that it never does it when the motor is cold...

    Thanks for ideas...
     
  8. Feb 22, 2020
    baldjosh

    baldjosh Member

    pacific north west
    Joined:
    Oct 24, 2017
    Messages:
    451
    in the video just before the 2:20 mark is a hiccup noise....and then again at the same time the grinding starts, does it make those noises every time?
    that's a weird sound...
     
  9. Feb 22, 2020
    ardan

    ardan Member

    West Tennessee
    Joined:
    Mar 19, 2019
    Messages:
    52
    Yes, Everytime it does 3 or 4 very short grinding (hiccups) and then a few seconds later it is constant from that point on.
     
  10. Feb 22, 2020
    garage gnome

    garage gnome ECJ5 welder

    Western MA
    Joined:
    Jun 19, 2009
    Messages:
    3,083
    I'd pull the timing cover off and see what going on. It sounds like a rubbing/grinding noise.
     
  11. Feb 22, 2020
    Howard Eisenhauer

    Howard Eisenhauer Administrator Staff Member

    Tantallon, Nova...
    Joined:
    Nov 22, 2003
    Messages:
    8,102
    Did you do any work on the engine? I'd pull the cover & pan & check out the front bearing, I'd say you're ok till the oil heats up & looses viscosity.
     
    scoutpilot likes this.
  12. Feb 22, 2020
    ardan

    ardan Member

    West Tennessee
    Joined:
    Mar 19, 2019
    Messages:
    52
    We rebuild everything but the internals of the engine. We did pull the timing cover and clean it up and replace the gaskets put in new bolts etc.

    Thanks for all the feedback, I will pull the oil pan and cover again and see what I can find.
     
  13. Feb 22, 2020
    Howard Eisenhauer

    Howard Eisenhauer Administrator Staff Member

    Tantallon, Nova...
    Joined:
    Nov 22, 2003
    Messages:
    8,102
    I know it's disheartening but this isn't a major operation.
     
  14. Feb 26, 2020
    DoubleBit

    DoubleBit Member

    East of Auburn, CA
    Joined:
    Mar 27, 2003
    Messages:
    62
    Had a noise like that on a Hurricane motor, turned to be a cracked belt pulley at the crankshaft end.
     
  15. Feb 26, 2020
    Glenn

    Glenn Kinda grumpy old man Staff Member

    Apopka, Fl
    Joined:
    Sep 21, 2002
    Messages:
    12,367
    Didn't sound mechanical to me. Temperature related apparently, cooling system related? Stuck thermostat? Maybe pressure builds enough, just a bit of water is forced by? If water isn't circulating 140 degrees isn't an accurate number.

    I think I would take the thermostat out and try it without it before anything else. And definitely put the fan belt back on.
     
    Last edited: Feb 26, 2020
  16. Feb 26, 2020
    ITLKSEZ

    ITLKSEZ Hope for the best, prepare for the worst

    Liberty Lake, WA
    Joined:
    Aug 13, 2015
    Messages:
    6,656
    That really sounds like dry bearing or bushing chatter to me.

    Dry distributor shaft?

    Just for kicks, next time it does it, push the clutch in and see if it changes.
     
  17. Feb 26, 2020
    Glenn

    Glenn Kinda grumpy old man Staff Member

    Apopka, Fl
    Joined:
    Sep 21, 2002
    Messages:
    12,367
    Why does it not make the noise as soon as it's running though?
     
  18. Feb 26, 2020
    scoutpilot

    scoutpilot Member

    Asheboro, NC
    Joined:
    Jun 7, 2014
    Messages:
    428
    What is your idle rpm?
     
  19. Feb 26, 2020
    ITLKSEZ

    ITLKSEZ Hope for the best, prepare for the worst

    Liberty Lake, WA
    Joined:
    Aug 13, 2015
    Messages:
    6,656
    Maybe there’s enough slop in the bushings to spin freely until friction causes it to heat up, then it expands and starts to bind.

    My bench grinder does the exact same thing. :D
     
  20. Feb 26, 2020
    Glenn

    Glenn Kinda grumpy old man Staff Member

    Apopka, Fl
    Joined:
    Sep 21, 2002
    Messages:
    12,367
    I have one that makes noise as soon as it starts spinning. Needless to say I don't use it. :lol:
     
    ITLKSEZ likes this.
New Posts