Cracked case at oil plug

[Guest]

My 425 has developed a leak at the drain plug. At first I thought it was loose and leaking, so I put a wrench on it, and it was tight. I cleaned off the oil, and at the back of the hole in the case, there's a small crack. I tried putting on form-a-gasket on the plug, but the crack must go higher than the plug goes in. Any ideas how I can fix it? JB Weld? threaded insert,(although I don't know if there's enough material there to do that), more silicon?

[chef1366]

Get a used oil pan off Fleabay.

[rphillips]

Sounds like the plan

[fabinator]

Good thing it's only the pan, but finding a replacement may take awhile. If you have an alternative source of transportation, you can have the crank in the pan TIG welded, then re-thread the drain hole. I think the oil drain plug has M14X1.25 threads, you could measure the bolt to be sure.

On my GS450, the oil drain plug has the same thread count as the spark plugs... you may be able to use a spark plug tap to re-thread the hole.

[SteveN]

Thanks for the help. I don't believe the twins have a separate oil pan. The oil plug is in the rear bottom of the crankcase. Has anyone fixed a cracked case?

[SteveN]

Thanks for the help. I don't believe the twins have a separate oil pan. The oil plug is in the rear bottom of the crankcase. Has anyone fixed a cracked case?

[SteveN]

Sorry, didn't mean to post that twice

[fabinator]

I checked the microfiche for the '79 gs425, and it does show a seperate oil pan. However, there is no longer a part number or price listed, so it's been discontinued.

[t3rmin]

I think I'd try JB Weld. This is exactly the sort of thing they advertise it being used for. It'll handle the oil and heat.

If you're careful and don't slather it all over willy-nilly so it breaks loose and clogs something, you've really got nothing to loose. And it's easy...

The key will be to get the surfaces clean so it bonds.

The only question I'd have is will the drain plug spread the crack a bit when it's tightened (probably). You might want to apply the JB Weld, then insert and tighten the plug while it's still wet, if you can do so without bonding the plug to the pan permanently (maybe spray the plug with WD-40 first?).

[BassCliff]

Parts is parts

Mr. SteveN,

I just did a quick check on ebay and found a few used parts that should work for you. Hope this helps.

Thank you for your indulgence,

BassCliff

[SteveN]

Thanks for the replies. I'll go look again and see what I missed.

[germanicus]

Just curious, did you solve the problem?
I think my bike has a crack in the same spot. There's what looks like JB Weld around the oil plug and I'm due for an oil change...
Cheers