Knock came and knock left
#1
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Knock came and knock left
I ran my superboat last week for about 2 hours. Came home flushed it out and the motor started knocking after about 2 minutes on the hose. Removed oil filter,cut open and found nothing. Fast forward to today. New filter,ran on hose for about 30 minutes 155-160 degrees no knock.Oil pressure 40-45 at idle. Its a 502 efi aluminum heads Imco exhaust with Eddie Marine slip in mufflers. Any thoughts? Thanks
#5
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X2. And yes, they will make a hell of a racket - especially if they're getting worn. Try running the boat off the hose again starting with the drive down. Then raise it up slowly to see if you replicate the sound.
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Ok so the u-joints turn even in neutral ? Just curious,how fast are they turning. I forgot to mention that its a Bravo one drive if that matters
Last edited by jponfrank; 08-31-2014 at 07:51 PM.
#9
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Start it and turn the wheel hard over side to side. If it knocks when it is hard over most likely u-joints but could be a dry gimbal bearing too . If it knocks pump some grease into the gimbal bearing Zert and restatrt and repeat side to side motion . If you still hear the noise it is time for new universals.
Dry Gimbal bearings make a hell of a racket on the hose in the driveway that most likely you would not hear over the exhaust while out on the water.
Dry Gimbal bearings make a hell of a racket on the hose in the driveway that most likely you would not hear over the exhaust while out on the water.
#10
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The shift cable is actually switching inside the drive. You will have to disconnect when/if you pull drive. I would suggest pulling it to grease u joint and feel gimbal bearing. Cheap insurance. "Youtube" is your friend. I have done more work than I could have by reading these forums and watching videos!!