Tranny oil leak UPDATE

Hey guys, so I have an update for you. I asked what would be the cause for my transmission oil drain plug leaking oil and a few of you suggested that I would need a new sealing washer. So I went out riding for the weekend at Ocotillo Wells and after I came back, changed the oil and washer. Turns out the threads are stripped on the hole in the crankcase :thumbsup: I then went riding the following day and I tipped the bike over twice and cased it on a 75 foot double. When I was loading our bikes up I noticed a steady drip from the bolt.

The bolt doesn't get very tight at all, so I'm wondering this: HOW SCREWED AM I? Is there a way to rethread that hole or am I going to need a new crankcase cover?(not sure of the proper name) I was thinking of just epoxying the bolt closed and just topping the oil off everytime I ride to keep it fresh, and then in a couple months, when I get the money together, buying a whole new bottom end and replacing it and fixing the old one.

Any thoughts or comments would really be appreciated. Thanks!

I would just tap in some new threads and buy a bigger bolt but if you don't have access to a tap than you could try jb weld, it's softer than epoxy and might be easier to take off when it's time for an oil change.

You can't jb weld this hole, its inside the motor. It isn't a case cover either unfortunatly, its an actual case half.. as in to replace the entire motor comes apart. And tapping new threads is tough as it is so far in there. I know your pain, if you look on Ebay at an actual picture of a case half, the area where the threads are has a "bridge" of aluminum that the threads are tapped into. It is a SHITTY DESIGN, as this piece that has the threads can literally break out of the corner of the case it is located in.

You Can TRY a slightly larger bolt, i found one at PepBoys auto center that had a 13mm hex head. This worked for awhile, but i continued to see small shavings when i would drain the oil from the threads that continued to deteriorate, then the "bridge" broke off inside. That in turn ruined a few gears as 4th would skip under power..

Another thing.. The slightly larger bolt i used had to be turned down on a lathe as the one of the gears would slightly hit it. (not the threads, higher up on the bolt toward the head).

People want STUPID money for case halves on ebay, and although the bearings are already there, you don't know how old they are. I was able to have a GOOD welder tig in some new aluminum, and helicoil new threads. There literally was nothing to tap into.

From there, i drilled the new drain bolt head and ran safety wire through it. Then tighen gently and run the safety wire over to the brake side frame rail and it is fine.

Go to the hardware store and buy a 5mm longer bolt. This will allow you to reach deeper into some undamaged threads in the case. I always use a torque wrench on the oil drain bolts. They require only 12 ft/lbs and they are very easy to strip out if you are heavy handed with your wrench.

You can't jb weld this hole, its inside the motor. It isn't a case cover either unfortunatly, its an actual case half.. as in to replace the entire motor comes apart. And tapping new threads is tough as it is so far in there. I know your pain, if you look on Ebay at an actual picture of a case half, the area where the threads are has a "bridge" of aluminum that the threads are tapped into. It is a SHITTY DESIGN, as this piece that has the threads can literally break out of the corner of the case it is located in.

You Can TRY a slightly larger bolt, i found one at PepBoys auto center that had a 13mm hex head. This worked for awhile, but i continued to see small shavings when i would drain the oil from the threads that continued to deteriorate, then the "bridge" broke off inside. That in turn ruined a few gears as 4th would skip under power..

Another thing.. The slightly larger bolt i used had to be turned down on a lathe as the one of the gears would slightly hit it. (not the threads, higher up on the bolt toward the head).

People want STUPID money for case halves on ebay, and although the bearings are already there, you don't know how old they are. I was able to have a GOOD welder tig in some new aluminum, and helicoil new threads. There literally was nothing to tap into.

From there, i drilled the new drain bolt head and ran safety wire through it. Then tighen gently and run the safety wire over to the brake side frame rail and it is fine.

Seems like a big hassle. If I can find a bottom end on eBay for a decent amount, I think I'll just go with that.

Go to the hardware store and buy a 5mm longer bolt. This will allow you to reach deeper into some undamaged threads in the case. I always use a torque wrench on the oil drain bolts. They require only 12 ft/lbs and they are very easy to strip out if you are heavy handed with your wrench.

Yeah, I think the last owner worked on cars/trucks too much and got kind of careless.

Seems like a big hassle. If I can find a bottom end on eBay for a decent amount, I think I'll just go with that.

.. provided you get a good case half, and the threads are not buggered any worse than you have now. Ebay can be a crap-shoot. And there is the bearing issue. I agree, if it works out and ya get a great used case half your way ahead.. But, having a pro welder fix up your current case half, assuming you have good bearings already and no other damage.. you KNOW what you have.

As pointed out in an above post, try to find a slightly longer bolt. If you remove the right side case cover (not just the round clutch cover but the whole case cover) you can see the small hold that allows the oil to drain from the clutch side. This will allow you to see how far in the new bolt is threading in, you can add an extra washer or cut the bolt and clean the threads with a tap/die set. Either way, your gonna need to take extra care from here on out. Safety wire the bolt is not a bad way to go, an extra minute or so each oil change.

A good friend of mine went through this last year. A long pulley tap and a longer bolt fixed it without splitting the cases.

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