1998 Mercury 150 xr4 " knocking noise " after engine cut-off at idle?

[Aaron French]

Last weekend something caused a short in my boat engine / upper unit. The modular and several wires burnt. I hired an individual who replaced the burnt wires, modular and put-in new spark plugs. We briefly started the motor after the repairs (for less than five minutes) and the batteries were checked to see if the charging system was working, and it was fine. The motor was then turned off.

The repair person told me to wait for about an hour and then run the boat because the silicone applied needed to dry. A few hours later, I took the boat out and ran it. It seemed fine. Coming into the dock, I put the boat throttle in idle, and it cut-off and made a clicking or knocking sound from the upper part of the engine.

This happed a second time after I restated the boat. It cut out while in idle, and made the knocking noise for at least 6 or more times, the knocking sound. It was fairly loud.

I pulled the boat into the dock and I have not started it since. I do not want to damage anything as I am not familiar enough with boat engines.

Does anyone have any idea why it's making the clicking or knocking noise after it cuts-off?

My engine did NOT do this before the repairs that were recently made. I do not know if it could be related.

 

[Dukedog]

just a little info ta start... tha XR4's last year was '90/'91.... XR6 maybe?.... "ANY" strange, loud enough ta hear with it runin', clickin' and/or knockin' needs ta be found before ya run any more.... it won't just go away..... normally only thing that makes tha sound you describe is a bearin' of some sort... have seen stator ta flywheel "rub" for whatever reason make some strange noises....still hard ta say ona computer

curious?... where did he use "silicone"?

 

[sam am I]

Guessing a magnet or a magnet piece (from up and under on inside of flywheel) came loose which perhaps caused the short in the first place. He may have used silicone to try to stick it back on and it just came loose.

Weird that it would only make the noise when it cuts out though but, maybe it's a centrifugal force thing going on, not sure. Its one place I'd at least start looking at.

Epoxy I think is what is used to repair normal if it can be repaired that is

http://www.informationaboutboats.com...wheel-magnets/

http://www.thehulltruth.com/boating-...000-hours.html