Announcement

Collapse
No announcement yet.

Rattle of Sorts-Engine

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Engine: Rattle of Sorts-Engine

    I have a '63 GT, standard 289, 4 barrel, Powershift trans. No power steering, brakes, or AC. I have a "rattle" sound eminating from the engine. Not there when cold, more when it warms up. If I "blip" the throttle it will go away momentarily, sometimes for a little bit. Tried listening everywhere (Val covers, fuel pump, block, tranny) to get a focus on it to no avail. My Father (81 years old ) thinks it is lifters and said he'd start there. They were adjusted about 3K miles ago but certainly easy enough to start. Just wanted to see what other ideas are out there. The noise started only doing it occassionally, but now it does it all the time. Oil pressure is good at 40 psi without too much variability (I've seen what an old tired out engines oil pressure can do when running it through the revs). Any insights highly appreciated.

  • #2
    Put a stick or mechanics stethoscope down on the bell housing, Have someone put in gear with brakes hard on, so you don't get hurt, have them put it gear and lightly torque the engine against the brakes to see if you hear any change in sound. If it changed, I'd look towards a cracked flex-plate. Unfortunately seeing it in the car is almost impossible as it hides behind the torque converter, and cracks up near the crank bolts, and makes a noise similar to a soft ticking-knocking as it flexes from torque, crank thrust and heat differential. It will sometimes come and go when "blipping" the throttle especially under load.
    Last edited by karterfred88; 06-17-2016, 06:53 AM.

    Comment


    • #3
      Having had broken flex plates in the past, I second the notion. Usually, a broken flex plate makes the most noise at no load. If the engine is pulling hard, it should be quiet.
      Gord Richmond, within Weasel range of the Alberta Badlands

      Comment


      • #4
        But why did the flex plate crack? better check bell housing to block alignment and while there double up on the flex plate, especially if no mis alignment is found. BTDT. Luck Doofus

        Comment


        • #5
          Unfortunately flex plates-aligned or not crack They work by "flexing", allowing the converter to move toward and out from the engine as it heat cycles. Like a beer can eventually cracks, the center is held tight but the outside moves in and out, flexing. The dialing in helps by only making it flex as "designed" and not also at an angle, but in time they all crack. Look at some flex plates from other cars and the holes, stamped reinforcements used to try and compensate and improve life. Ours were early designs and more prone to it.

          Comment


          • #6
            Yep, just put a broom handle down on the Converter housing from the Top and to your ear and listen, safer than under it since it may make more noise at idle in Neutral or idling in gear.
            StudeRich
            Second Generation Stude Driver,
            Proud '54 Starliner Owner

            Comment


            • #7
              Originally posted by StudeRich View Post
              Yep, just put a broom handle down on the Converter housing from the Top and to your ear and listen, safer than under it since it may make more noise at idle in Neutral or idling in gear.
              So if cracked, would that mean an engine pull?

              Comment


              • #8
                I thought the flex plate problem increases with throttle ? How about something simple like a NORS heat riser valve ??

                Comment


                • #9
                  Originally posted by CKOT View Post
                  So if cracked, would that mean an engine pull?
                  On a Hawk, easier to first pull the transmission from the bell housing, set it aside, and then support the rear of the engine, and remove the bell housing to access and replace the flex plate. You might have to remove the batwing crossmember. Probably also should replace the 2 transmission mounts while you are in there, unless they are known to be new, or appear to be perfect.

                  They knock most at idle because the torque converter is the engine's flywheel, and the flex plate is what links it to the engine. The engine puts out torque in pulses, while inertia makes the flywheel want to turn at a steady rate, so the slack formed by the cracks is alternately closed and opened, hence the rattle. Under load, the slack is taken up on one side and mostly held there, so less noise.
                  Gord Richmond, within Weasel range of the Alberta Badlands

                  Comment


                  • #10
                    I had a similar noise problem with my 56J. Although not the same engines (!), you might want to check the vibration dampener. Mine was sheared at the rubber vulcanizing and made a rattling sound similar to your description. I could be way off base.

                    Bill L.
                    Bill L.
                    1962 GT Hawk

                    Comment


                    • #11
                      I know this sounds too simple but give this a quick look as well.

                      When I fist got my Avanti running, there was a sound coming from the bellhousing and I assumed the worst, a cracked flex plate. Since the car was not yet roadable (I was driving only up and down a long driveway), I didn't leap to the problem. In looking everything over, there was one detail I realized I had missed, trans fluid level. Yes, I knew that the fluid had to be up to temperature and the engine running, what I had never seen was that the transmission needs to be in DRIVE! Once I picked up on that little detail, I found I was more than a quart low! Once the quart was added, clattering noise was gone. I am guessing the front pump wasn't too happy before the top up.

                      Comment


                      • #12
                        I am sure you have an alternator, but my generator is rattleing. Take the belt off and run it. Water pumps can rattle too.

                        Comment

                        Working...
                        X