Tapping/ticking noise
#1
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Ok, I had my 454 mag EFI (385 hp) engine rebuilt 2 years ago. Since then Ive put 50 hours on it. The boat runs awesome (tons of power and it sounds perfect) but this morning I noticed a loud ticking noise coming from the back of the motor (at idle). I cant seem to isolate it to either side. It just seems too loud to be flappers. I havent even run the boat hard this week--Im in AZ at the Desert Storm (nothing over 4000 rpm) but it has been sitting all winter (this is the first use of the year). Im guessing a stuck lifter. What is the best way to free it? Additive?
#2
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Exhaust flappers can sound like a rod knock and nearly as loud. Put your hand on the rubber exhaust hose and you can feel them.
If the noise goes away when you throttle up to about 1200-1500rpms, then its probably internal exhaust flappers.
If the noise goes away when you throttle up to about 1200-1500rpms, then its probably internal exhaust flappers.
#3
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Ok, well I revved the engine up to 1500 rpm in neutral and can still hear the ticking noise. Still kind of scratching my head here....Lots of power and the engine sounds perfect from 1500 to 4000 rpm (i havent gone past 4000). should I worry about this? Possibilities are valve, rocker or spring right? How would I diagnose?
#5
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Take a piece of water hose 4' or so and hold it to your ear then swipe the valve covers with the other end till you can hear the ticking and locate exactly where it is. Works just like a Dr. Stethoscope
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I had the same thing happen last summer on a 27 baja 454 mag 385 hp. I pulled the valve covers and checked for loose rocker arms etc, all looked fine. I finally said screw it and just went boating as usual.
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