Posting this for a bud with a '93 EVO Softail. He has developed a leak in the front of the engine where the cases split behind the oil filter. There is a bolt which threads into the right side of the case after passing through the left half. This is the only bolt that doesnt pass through both halves and have a nut on the other end. His bolt is stripped in the case and cannot be tapped for fear of shavings ending up in the engine. He is not sure if the bolt passes through the crank case before threading into the other half. He also was wondering if this could be drilled all the way through and put a longer bolt with nut on the other end. Hope this makes sense...hard to explain and envision while sitting on the couch. Anyone have a clue for a fix without tearing the engine down? If cases were split this would be a no brainer but trying to avoid a total disassembly. Thanks. MIke
OK..hobbled out to garage and got my '91 EVO manual. If the '93 is the same block as mine, I am referring to crankcase stud bolt (3/8 x 3-1/4). Position 7 in the torque sequence. I was wrong before. There are two of these studs it seems looking at the diagram. Hard to tell.
had to go look at my 5 motors, not one has a clear shot at the other side with that bolt cuz the cam chest is in the way...
The bolts are outside the o-ring seal and the cases butt up to each other hard an fast, so he can maybe/probably tap without anything getting into the cases, just don't know how far he can drill and tap before driving into the cam chest...
It sounds to me like he developed a leak and then just tried to crank down on the bolt to try to stop it. Always remove the bolt first,clean it up, put anti-seize the bolt, insert and re-torque. Now for the repair. Purchase a thread repair kit {insert or coil type kit}. You will only be drilling enough to remove the damaged threads, then install the insert. The kit will or should come with everything you need. If it continues to leak you may want to consider having the cases pulled apart. I personally wouldn't drill all the way through. There is also a product out there that comes in a spray can that's used to stop leaks in pipes. I don't remember the name of it but it may good enough for a temporary fix
My first thought was tapping or a coil like you guys said. Thinking the only problem may be is getting that far in to repair. Tapping may be easier than inserting a coil. He has to get past the left case half first. Im sure it can be done...but hes a bit of a butcher...LOL! Obviously he overtightened as you said MTYEVO. Thanks for the info.
There is NO way to repair that threaded hole without splitting the cases,save your friend the cost of having to replace his cases & have someone who is not a butcher repair them.There are numerous ways to destroy these cases trying to repair them while they are assembled,even if you could buy a helicoil tap & installation tool long enough to clear the left case there are still too many ways to turn the right case into an expensive paperweight!
EVO Engine Block Leak 
Linear Mode
