Tracking Down Oil Leak (after crash). Could it be a crankcase gasket?

[Guest]

Sadly, I put my GS850 down on its side a few months ago. I took care of all the issues from that (sliding into a curb at even 10km/hr is enough to bend the front forks, wheel AND axle, it seems) but for one: I have sprung a gentle oil leak.

The corner of the crankcase cover (over the stator) got scraped when the bike hit the ground but it did not seem to wear through. There is oil leaking from somewhere behind it and dripping down off the corner of the cover. It's a minor leak but I'd rather not stain the driveway... or have a leaking bike.

Any ideas on where it might be coming from?

My only thought is that perhaps the impact with the ground nudged the crankcase cover enough to break the gasket seal. The bike is new to me so I'll assume it still has a 30 year old set of gaskets, though two owners back seemed to have done good work (over a decade ago at this point).

My plan right now is to track down a crankcase gasket, unscrew the cover, replace the gasket, then reassemble. I have very limited experience here so I'd love a heads-up if the task is more complicated than it sounds.

Any other ideas for places I should check for an oil leak?

[eil]

A pic might help, but if you can't see the source offhand, perhaps not.

Standard advice is to clean the engine very well with your solvent of choice, let it dry, cover the suspected area (or heck, the whole engine) in baby powder, talc, or perhaps even flour, and then run it until the leak becomes self evident. Works 100% of the time.

My plan right now is to track down a crankcase gasket, unscrew the cover, replace the gasket, then reassemble. I have very limited experience here so I'd love a heads-up if the task is more complicated than it sounds.

Replacing the gasket under the stator cover is no big deal. If you don't want to drain the oil, I read that you can put the bike on the centerstand and then get a 2x4 under the left leg of the stand. If the cover is still held on by the original screws, get an impact driver to remove them. You'll thank me later.

Once you have the cover off, clean both mating surfaces very well, inspect your stator and everything else underneath for good measure, and then reinstall the cover with new stainless steel allen-head bolts and copper anti-seize. Torque to specified value and Robert is your mother's brother.

[chuck hahn]

Dont even need a 2X4. only a few ounces will come out when you take off the cover. Lay a rag down, break the bolts loose and do the work.

And another thing to note...pressing on the bolts or smacking them with a 2X4 under one side will tip the bike over. want to see the pictures of the tank on my 78 1000C after the 78750 did just that??? Do as you all wish but I advise against it.

[steeper]

Glad to hear the crankcase cover removal won't be overly complicated.

I'd try the baby powder trick, but I'm afraid I don't have any. I'll see if baking soda will stay in place and do the job. The leak is slow (two or three drops, maybe, overnight after a ride) so it's more of a seeping of oil that moistens things than a drip that I can trace.

The PO told me he'd changed the oil at the beginning of the summer, but it's far too dirty for that to be true. It's probably for the best if I give it an extra oil change right now, while I'm at it. After fixing the damage from putting the bike down once, I'm not sure I want to risk balancing things on 2x4s.

[chuck hahn]

If your gonna change the oil theres absolutely no need for any boards. and like i said, its only afew opunces thats in the cover and doesnt drin back to the sump that wopuld come out anyway.

[tkent02]

Still you should pinpoint the leak before you take anything apart. If the cover has a tiny crack, or worse if the case does, you don't want to open it up until you have the parts to replace the stator cover, or the time and place lined up to repair or replace the case. Foot powder spray works well, but any type of spray powder works very well. Anything that will cover the area and show the oil.

Just like the old joke.

Hopefully it's just the gasket.

[steeper]

Bad news. Noticed something new. Cracked crankcase cover... good call, tkent02. Glad I saw your comment and decided to take a closer look.

Picture here.

Any thoughts on a cheap fix?

I'm thinking about asking my buddy, who's a welder, if he can take it and tack on a few layers of aluminum weld over top of it. That should seal the crack and maybe even give it some strength. Is there any reason this is a horrible idea?

[tkent02]

Cheap fix, JB Weld. Temporary repair that will probably outlast the rest of the bike. There are thousands of dirt bikes with much bigger holes than that JB Welded back together, it works fine. Use the good stuff, not the five minute. It is epoxy glue with metal particles in it, very very strong. There are other brands that are as good, just don't get some cheap crap that says it fixes everything.

Mix it well, apply it to a clean dry surface, in a larger area than you think it needs. You can file it down and paint the cover, it won't even be that visible. Replace the cover is another choice. Getting it welded is harder, the aluminum is porous and the metal has oil in it, won't weld very well. Worth a try perhaps if it's free. Is he good? He could make mess that JB can't fix. Welding aluminum is hard even without the oil.

If it were mine, unless it's a real live show bike in a real live show, I'd JB it and forget about it. No one will ever see it if they don't get down there and look.

[tkent02]

I think I have the stator cover you need, should be the same part number as a 1977 GS 750 cover? If it is I have one.

[steeper]

tkent: thanks for the offer. I'm not sure if it's the same part or not. Regardless, I showed the crack to my welder friend and he thinks it'll be easy to fix up. And he even said he'd use his shop's equipment and give the whole part a good spitshine. Can't pass up on that deal.

It'll probably be a couple weeks before I find time to pull things apart. We'll see whether this fix works!

[chuck hahn]

Theres nothing in the way on the inside once you unbolt the stator. Have him weld it from both sides and just clean back the inside weld a little..just good insurance if h can hit both sides. Some build up on the outside and some reshaping and you can probably make it look pretty decent again.