I have a 17hp Kolher SV630 on a Troy-Bilt Bronco. The rear engine mount bolts keep loosening/falling out. I have tried lock washers and red locktite. What else can I do to stop this happening?
Chuck
Edit: Just realized this was double posted and in the wrong forum. Can a moderator please move it?
 

The red loctite should work however the threads need to be super clean.
 
Some brake cleaner would help..
 
Also, if you can put longer bolts in, then a nut on the other side (atop the engine flange mount). Of course there needs to be some room but that would keep it from loosening up..
 
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I have a can of brake cleaner, but it doesn't take the tube that directs the spray. I looked today for a can that did with no luck. Then I found a can of CRC brand contact cleaner that does have the tube. Will that work?
Chuck
 
Edit: Google says it will, but leaves a thin coating of lube...

If you want it further cleaned, some rubbing alcohol on a q-tip will get in there. 
It has to grease / oil free or it won't work as designed..
 
Do you have room for longer bolts and additional nuts?
 
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I don't think I have room for extra nut and lock washer. I sprayed the threads of the hole and bolt with brale cleaner and used new red permanent locker. We'll see if it holds later today.
 
Chuck
 
Edit: This must be a common problem. I had the same issue with the predecessor MTD machine with a Tecumseh motor. ended up putting helicoils in the mount holes and using thread locker. I'm older and in poorer health and didn't want to remove the engine on this one.
 

The engine doesn't need to be removed.  
 
You can remove one bolt at a time, go to the hardware store, and get one 1/2" longer.
You won't need an ADDITIONAL lock washer.  The nut on top will lock everything up..
 
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