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Discussion Starter #1
I recently picked up a 2011 Brute Force 750 that has a loud ticking sound coming from the engine. I believe the prior owner ran it low on oil. I'm trying to confirm if I spun a crank bearing or hopefully something much less severe. Please listen to the attached video of the noise.

Here is what I have done so far to try and locate where the noise is coming from:

  • adjusted valves, both were a little tight but close to service manual specs. The adjustments did not make the noise go away.
  • Checked the tension on both cam chains. Both tensioners were less than halfway extended.
  • Used a mechanics stethoscope to try and pinpoint the noise. I couldn’t tell where it was coming from.
  • The front cylinder was on the lower end of compression at approximately 32 PSI and the rear was at 50. I pulled the front head to examine the piston and valves to see if it could have been valve related. I did not recognize any visible piston or valve damage and the valve guides and seats looked ok (see pictures).
  • Removed the left side alternator cover to inspect the intermediate and oil pump chains. Not sure how to compare if they are stretched beyond their limits. See attached pictures.
I really appreciate any insight on what you suspect the sound is and what else I need to troubleshoot.


Engine Video 1

Engine Video 2

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Piston.jpg
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Discussion Starter #2
I forgot to mention I found a small exhaust leak during disassembly. Any chance that this could be the culprit?
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That exhaust leak is probably your problem. I just fixed some leaks in mine and my engine quieted down incredibly. Sounded like tight valves and then fixed the exhaust and went quiet again. I would check over all the exhaust. Seems like I’m seeing a lot of people start to have problems with them rotting out and cracking unfortunately. Happening to me now, having to replace both pipes and they aren’t cheap
 

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That's not an exhaust leak sound. That is definitely a mechanical tick such as a valve, valve spring or rocker arm problem. Shouldn't be a cam chain as they make a continuous noise when they stretch out. Gotta be valve train IMO.
 

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I’m just saying. I just had this exact thing happen, sounded like a mis adjusted valve and then I found exhaust leak and boom, it went quiet again. You’ll need to have a fully sealed exhaust before you can start really hearing where your noise is coming from
 

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Curious what this turns out to be. You could get some cheap exhaust repair wrap from the auto parts store as a temporary way to seal up the exhaust pipe.
 

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A similar thread that can help you find out the reason behind the loud ticking sound.
 

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I recently picked up a 2011 Brute Force 750 that has a loud ticking sound coming from the engine. I believe the prior owner ran it low on oil. I'm trying to confirm if I spun a crank bearing or hopefully something much less severe. Please listen to the attached video of the noise.

Here is what I have done so far to try and locate where the noise is coming from:

  • adjusted valves, both were a little tight but close to service manual specs. The adjustments did not make the noise go away.
  • Checked the tension on both cam chains. Both tensioners were less than halfway extended.
  • Used a mechanics stethoscope to try and pinpoint the noise. I couldn’t tell where it was coming from.
  • The front cylinder was on the lower end of compression at approximately 32 PSI and the rear was at 50. I pulled the front head to examine the piston and valves to see if it could have been valve related. I did not recognize any visible piston or valve damage and the valve guides and seats looked ok (see pictures).
  • Removed the left side alternator cover to inspect the intermediate and oil pump chains. Not sure how to compare if they are stretched beyond their limits. See attached pictures.
I really appreciate any insight on what you suspect the sound is and what else I need to troubleshoot.


Engine Video 1

Engine Video 2

View attachment 75114 View attachment 75114 View attachment 75115 View attachment 75119 View attachment 75120 View attachment 75121
View attachment 75124
My 04 v force 700 was making the same noise and it ended up being the front cylinder had sit with coolant in it before I got it from a bad head gasket. It had left a really big ridge and pitted it up bad enough it had really bad piston slap. I had it honed 2mm over and put in New piston and rings and it's quiet like new now.
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Discussion Starter #10
Thanks everyone for sticking with me on this. I jumped back into diagnosing the engine last night and removed the feont cylinder to take a peek at the cylinder walls and to put eyes on the bottom end.

When looking at the connecting rod it appears that it is missing one of the two bolts that help secure it to the crankshaft. Also, there is what looks like a metal foil (almost similar to a wine bottle when you remove the cork) that is protruding out of the crankshaft that you can see in the left side of the picture.

  1. Whats my next move on this and any idea how this happens?
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Looking deep I see the casting looks pealed like that bolt got caught against it and the crank throw. You are looking at least a full rebuild with crank kit and that one rod will be shot now but the case camage has me worried. That could be a problem that can't be gotten around. You may well be looking at a new case as well.
 
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