[wagun]

New to this quality forum, however, I have been reading topics for several months.
After riding this weekend my bike was due for engine oil and filter change. When I replaced the drain bolt with a fresh washer and began to tighten I noticed a clicking/ slipping at or very near the bottom of the thread...
Further, the oil seemed to be leaking from the gasket between the crank cover and the case...I picked up a new bolt even though the original appeared fine hoping that the threads were damaged. That did not work. I laid the bike down a spotted the crack in my case. The LH crank case expands as a tighten the bolt and then gives exposing the crack...bummer.
How did that happen and what do I need to do to remedy?
My bike is a 2007 450X that I purchased in Fall 2014...this is the first of this problem. My buddy thinks I need to pull the engine and replace the LH case...thoughts? It is very unsettling to have my bike leaking oil and drained of fluids...
Please advise. Thx

[JimDirt]

Unfortunately it sounds like you will be replacing the case , the only other option (you will still have to remove the case) , is to find someone capable of welding it , it will need to be completely cleaned of any oil or grease , to be welded , and yes if its the inner case the motor will have to come out and be completely disassembled , if its just the ignition cover (Engine Oil not tranny oil) , then no you won't have to remove the engine , just remove the cover and either fix or replace , you will have to remove the stator assembly to do any repairs or to replace the cover as the new ignition cover will be without electrical components

Again , if its the tranny drain , then yes the engine will have to come out and be completely disassembled

As for the cause , at some point in its life (not necessarily you) , it was overtightened

Sorry for the bad news , but welcome to the site !!

[wagun]

thanks for the reply...is there anything else I should do while my guy is in there? Just looking for any suggestions...thx

[Back2-2]

To do it right ....It is as JD stated. Remove the case and either replace or repair.

Here is a option I would at least try -

Drain the oil and use a cleaner to completely flush oil from the case and crack. File a "V" in the crack. Rough up the area around the crack and clean, clean & clean the crack and area out. use a heat gun to heat the area up and make sure no oil migrates through the crack.
Mix up some 3M epoxy patch [ or JD weld if 3M is not avail.] to make a patch over the area. Let completely dry [ use a heat gun to aid the bonding process].

2-3 days later refill and reinstall the drain bolt with light torque to see if it will hold. I would use approximately 3/4 of the designated torque called out.

See if that works. 50/50 chance, but it's free and easy to try. Guarantee it's easier than pulling the engine down to square one !

[JimDirt]

If in fact it is the inner case , then while its "apart" , and if it has a few good hours on it (100+) , i would replace the piston , and timing chain , at the least replace the timing chain , make sure the valves are good (check the Intake shim size , if its near or at 1.20 on either side , then a valve job is imminent , if so i would recommend Stainless) , if its just the outer ignition cover , i would still replace the timing chain

When re-assembling put 1 full qt. in the tranny side , this is common practice with the X to avoid possible tranny issues (i do it in my 450R as well) . make sure your jetted for your elevation , and get some "Engine Ice" coolant , it will keep the engine temps up to 50 degrees cooler , which will help when slow going on a trail and will add to the longevity of the engine overall , just make sure to completely flush all the old coolant out (i use distilled water to flush the engine clean , as the Ice does not mix well with other coolants) , ....... that should get you started anyway

[wagun]

really good stuff...thx to all