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Discussion Starter #1
Hi guys this is my first post and I hope some of you more experienced guys can help,I have a mv agusta f4 750 evo3 with 9000 miles which I use as second bike at weekends. Last Sunday I was out for a blast when I came to a junction and stopped, there was then an almighty banging and clattering from the engine as if something broke off and was grinding up going down through the engine to the sump, it only lasted about 5 seconds and then quietened down to a low constant ticking. I rode bike home and let it cool down and took it out a few more times with same ticking symptoms at all rev ranges no loss of power and no difference even if you pull in clutch just constant tick-tick- tick. I decided to strip bike to include checking timing ,valve clearances, timing chain, cam lobes, timing chain tensioner, also to see if any bolts came loose in the head area, also removed water pump to see if impeller had imploded, continued to drain oil with no metal filings, then removed sump and it was spotless ,looked up into engine and all looks perfect. I am completely stumped as to what the awful noise was and why I have been left with ticking noise. Forgot to say also checked both fans. Sorry this is so long but I wanted to cover everything I have checked to date, would anyone have any ideas what I could have missed or what that awful noise was and why I have been left with this constant ticking before I build bike back up
thanks
 

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Did you look inside the cylinder head?
 
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One possibility is that your engine ingested one of the well nut brass ferrules that fasten the rear of the Injector Covers to the Air Box.
 

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Discussion Starter #4
I have just the timing chain cover off to inspect cams and chain might have to go deeper
 

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Pull the injector covers on the air box and see that the well nuts are intact.
 

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Discussion Starter #6
Sorry if I sound stupid but I have pulled of covers but can’t see the well nuts are they were the injectors enter the rail on inside
 

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Discussion Starter #7
Sorry silentservice wasn’t thinking straight there yes all 4 well nuts are in place they were all there when dismantling
 

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Discussion Starter #8
It wouldn’t be a main bearing? You would have thought that would be more a whining noise than a ticking also it wouldn’t have made all that grinding and crunching noise would it?
 

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The rearmost two well-nuts have a habit of dumping their inner brass ferrule into the intake tract.
You would either have to remove the airbox and verify the well-nuts contain their respective ferrules, or you would have to thread the holding screws in to ensure the brass insert is there.

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Discussion Starter #10
Hi I actually think you could be on to something as when I bought the bike before Christmas I decided to give it a strip down and clean when I removed airbox I notice one of the screws was missing and so I pulled well nut rubber out and replaced with one with nut and new screw so old nut must have been bouncing around inside and found its way down😡😡
Will this damage get worse as other than ticking it is riding perfectly?
Would I have to remove engine and total strip down to fix?
 

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The material of the nut that might have dropped into your intake tract will determine how much damage gets done. Softer materials will disintegrate faster doing less damage.

Me, I would have a look for the nut...and if it's missing, then I'd check inside each cylinder through the spark plug hole with a boroscope.
 
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I'm sure others will weigh in. Keep us posted on your progress and what you find.
 

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It is a brass threaded insert in the well nuts.... if lost into an intake it would likely catch on the valve face and result in a bent valve...and then, if lucky, go out the exhaust with not much other damage. Take off your throttle bodies and have a look into the intake valves. Your ticking could be a bent valve face hitting the piston.
Rotate the engine with a wrench on the crank and check the sealing of the intakes in each cylinder by looking down the intake tract.
With any luck the damage will be just the valve....but it could be top of piston, cylinder wall and an exhaust valve too.

A compression test and a leak down test will also confirm a damaged cylinder or valves.

Should you see no damage and get a good result from compression and leak down then I would suspect the timing chain tensioner.
 

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Discussion Starter #16
Just an update on progress, I took all of the advice above and first checked valve clearances all within spec 0.203 on exhaust and 0.152 on inlet, then checked timing chain and tensioner all seems to working fine , next was the leak down test with less than 5% leakage across all 4 cylinders which means valves must be ok.But then I done the boroscope test down each plug hole an there it was on no 1 piston brass nut embedded on top of the piston guess that’s were my ticking noise is coming from. It doesn’t seem to have damaged anything else, could a strong magnet lift this out as no other damage seems to have been done or any other easy fix other than removing head thanks
 

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As brass is non-magnetic, a magnet will not help in this situation.

If the material is loose, you could extend a wire with some sticky tape, or other material, securely fastened to it and see if you can capture it that way.

A very thin vacuum line is another option.

Is the brass imbedded in the piston?
 

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Hi! If the Brass ferrule is "embedded" in the piston, it may be possible to knock it loose through the sparkplug hole, then put blu-tack or similar on a piece of stiff wire and try to fish out the "offender"
Horror story ... :eek::oops:

Hope you get it sorted! Good luck!
 

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Wow...you got lucky there !! No valve damage !!
I think you need to pull the head to get that out and inspect the piston crown and combustion chamber for nicks and dents.
Pay attention to the head gasket...there are differing thicknesses. With luck you may be able to reuse the gasket with a copper gasket paint.
!
 
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