Please help! Cracked lower case

Docwits

Docwits

XS400 Enthusiast
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Went to drain the oil today so that I could remove the engine and found a very nasty surprise. The PO had said there was an oil leak, and I had seen some on the garage floor, but not enough to worry about till I got to the engine part of my build.

My guess is that the drain bolt was over torqued, either by wrench or impact gun.

Should I start looking for a new motor, either to use for parts or as a replacement? Can it be welded/repaired and then can I drain the oil by removing the filter plate?

The bike ran well, I rode it home, hadn't planned on a rebuild.

Thanks in advance for all of your help.
 
Sorry, here are pics.
 

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Here are 2 quick and dirty ways of "fixing" that.

1. Quiksteel - squash a blob in the cracks with the bolt in place then back out the bolt. This should create new thread in the crack. Quiksteel has been used to make all sorts of abominations - I mean repairs.

2. Use some hi-temp silicone to seal it up.

There are much smarter people than me on this forum so I would wait for their response before deciding to do anything. :bike:
 
Looks to me like it hit something solid. Notice it is 2 distinct cracks, one vertical and the other horizontal.

You may be able to find someone to TIG weld it, but the engine will have to be torn down and steam cleaned to remove all traces of oil before hand. If you decide to have it welded, make sure that they "stop drill" the cracks first. Literally, they drill a hole, usually 1/8", at the end of the crack so that it wont continue to crack. If they say it isn't needed, find someone else. This has to be done, regardless of how the cracks are repaired.
 
That is certainly the right way to repair it Dave, but what would something like that cost? A thousand? Possibly more?

I'd probably ghetto repair it with JB Weld or something and simply use the side drain instead.

My 1978 sohc has 2 different oil drain bolts. I'd imagine the oil could also be drained through the small round stator cover if necessary. It's annoying, but you can hold the bike sideways on the kick stand if it comes to it. That or use the oil filter cover.
 
Taken to a motorcycle shop as it sits, sure. But if the OP tears it down and boils the oil out of it, then takes it to a machine shop or welder, maybe an hour of shop time. Especially if the OP is willing to do the final grinding and polishing, or just accept the welds as they are.

I wasn't trying to suggest that it HAD to be welded. Bubble gum and duct tape would probably stop the leak, for a day or 2. JB Weld might work, with enough prep so it can stick. But without stop drilling the cracks, they will continue to grow.

Fixing it once is a bother. Fixing it twice is a PITA. A third time, well that is ghetto intelligence...
 
Haha, I was thinking that a JB Weld job might hold up until the rest of the motor gives out. At that point I'd just throw a new motor in.

I don't think too many people have it in them to do a complete tear-down.
 
Thanks for all the input guys! Tearing down the entire motor, just to have that fixed is not an idea I like, but will consider it. The PO did a top end rebuild on it, which I would be very comfortable doing, but once you start getting into the transmission I think the water may be too deep for me. Then again, I guess you never know until you try!

I am leaning towards a swap, something like the link below, would be nice to have the six speed trans. It should bolt right up to the maxim frame, shouldn't it?

Any adaptions needed to make, like sprocket or alignment issues?

www.ebay.com/itm/310335880354?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Now, nobody snag it from me!
 
Welding is certainly possible. I walked into a large industrial complex making high tech specialty equipment for industry. They took my part and gave it to their aluminum welder to play with. He repaired the crack, added considerable material to make it stronger than original. They only charged me $50 cash.
If you can drain the oil out of your crankcase a different way, then machining or threading would not be needed - just have the welder add material to fill the threaded hole with new aluminum.
 
Docwits said:
...Tearing down the entire motor, just to have that fixed is not an idea I like...
Click to expand...
Usually when they tear down a motor it's because parts need to be replaced deep in the bowels. The casings are not what gets fixed.
In your case, the internals are fine so you would not be taking anything apart if you didn't have to. Surely there must be a way to take the lower casing off without disturbing the innards. If so, then you could have it fixed 2 ways - complete repair with filling, machining and threading (expensive) or just welded such that there is no longer a drain plug (cheap).
Going cheap, one would have to drain the oil by removing the filter cover each timer. Messier yes, but you would have a running engine to continue using or trade for another.
 
I dont know if its worth it but I have heard what dave mentions about stopping the crack growing any further by drilling holes.It seems like a major PIA you have weight the balances of how much work is involved tear your engine down and have fixed the right way or do a bottom end swap.
 
I'e had good success with JB Weld on crankcases. Get it ABSOLUTELY clean though and mix that stuff right. Just don't do it when it's cold out. Scuff it up good too, maybe use brake cleaner to prep the area. When I cracked my case itr was an old KZ400 I tried to use a wrong kick starter on and then on a CB360 I laid down. Neither repair ever leaked oil again.
 
markjs said:
I'e had good success with JB Weld on crankcases ... Neither repair ever leaked oil again.
Click to expand...
Interesting. In DocWits' case, would you try and fill in the crack totally so that he could still screw the drain plug in and out? Or would you just plug it up with JB and drain the oil with the filter cover (on the Maxim, it is conveniently right on the very bottom)?
If the former, would you leave the bolt in to use it to mold threads in the JB? If so, might it need a coat of silicone spray to keep the JB from sticking?
 
I really can't say, as I did not have that issue but it can be machines after it hardens. It's a toughie no doubt...
 
Pork Chop said:
Guys, I think we are over complicating things. For me, part of the appeal of an old bike is that you can MacGyver quite alot of repairs... http://quiksteel.blogspot.com.au/p/strong-enough-to-lift-car.html?m=1
Click to expand...
You may be right. If riding is one's priority then MacGyverring is the thing.
Last year, I was good-naturedly chastised for even speaking the words JB-Weld. I suppose if one were a collector of authentic, original-only bikes, everything would have to be fixed to original specs with original materials. Some on here lean that way and I don't blame them when they have beautiful original bikes.
Would Jay Leno use JB or QuickSteel on anything other than a daily runner? :shrug:

On Wed, when my chain broke, it gouged the casing that boxes in the front sprocket. Used JB last night. Hope it dried without drooping too much. Will do a thread later tonight with pics.
 

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