What to do? Small hole in left case cover

[SpongeBobbed]

So I bought an '80 heritage special last summer to give me something to work on now that my bobber is running. I rode it a couple times and it leaked more oil than I thought possible. It had all the normal culprits, including a loose main sprocket, wrong/no gaskets everywhere, worn push rod and shifter seals, missing bolts exetera. I've spent probly 10 hours degreasing this engine (in frame) and I'm still not even close to getting all the caked on oil off it. I've been contemplating pulling the motor and soda blasting it but it seems to be strong and I don't want to pull it a part. I've heard you can soda blast a complete engine but I'm not sure if I trust it.

Anyways, I took off the left case cover today to clean the built up gunk by the sprocket and change the seals and I noticed a small hole by the bottom of the cover. I think oil has been leaking out of it but it's hard to tell because it was leaking everywhere.

My question is:

- do I have to replace the cover? I'd rather not if I don't have to
- If I fix up all the areas that leak oil from the left case (push rod, shift shaft, sprocket, etc) then I assume oil won't get into the left case. Am I wrong to assume that is supposed to be an oil free zone? other than what comes off the chain?
- since it is such a small hole can I just plug it up with some silicone or gasket maker? (I don't use it anywhere else on my bike but it might be helpful here)
- should it be welded?

Anyways, just wanted to get some expert opinions. Let me know what you think. Thanks!

 

[SpongeBobbed]

 

[Downeaster]

Mine has a drain like that under the alternator. If you've got oil coming out of it, the crank seal behind the alternator is shot.

If it's under the chain/sprocket, then you're on the right track by replacing the clutch pushrod seal, the sprocket seal and the shifter shaft seal.

There WILL be some mung flung (arrrrrr, poetry...) off the chain and build up in there, but it shouldn't drip unless you're over-oiling the chain.

 

[Royboy]

Sponged, Behind the left cover is where your electrics live. That "hole" you are looking at is an opening the factory put there to allow water and condensation to drain away. The clutch push rod seal is an infamous leaker on 650's and is probably the source of the oil you are seeing. The drive sprocket shaft seal just forward of the push rod is also a common leaker.

When things are correct in there you shouldn't see any oil behind the left case cover.

roy

Downeaster got up earlier than I did.!

 

[I am Carbon]

As DE stated it's a drain hole for the generator.
There should be no oil in there.
the main crank seal could be leaking mime was.
I haven't watched my video I a long time
If my memory is right i took the generaor. completely off ya don''t have to do that just let it hang to the side while performing the tast of replacing the seal

 

[gggGary]

Yes it's fairly rare but oil in the alternator compartment is most likely a crank seal. One member reported success doing an "in place" crank seal replacement. BUT and this has happened to me, oil from a leaking head gasket can sneak down the back of the cylinder, around the top case, into and through the alternator compartment.....

 

[SpongeBobbed]

Thanks guys! That was all super helpful. I guess I should have looked at my other engine to see if the "hole" was in the same place

The leak seems to be coming from the pushrod/main sprocket and not the main crank so hopefully I don't have to replace it. But I'll double check just to be sure. Much appreciated!!

 

[gggGary]

A leak from the starter gear cover happens now and then.

 

[I am Carbon]

don't know if you have replaced te push rod seal.
If you have not when you buy the push rod seal buy 2 good chance the first one will get messed up.
I used a dremel tool to bevel the edge to help not screwing up the seal

 

[5twins]

Many times the pushrod bushing needs replacing as well. A new seal will leak just as bad as the old one if the bushing is bad. Also, switching to the long one piece pushrod makes the seal's job easier. It wiggles side to side less.

 

[retiredgentleman]

SpongeBobbed;

Further to what 5twins has said; if you plan to replace the pushrod seal, do a simple test first. Hold the end of the pushrod, and try to wiggle it sideways. If you find any wiggle at all, the bushing behind the seal needs replacing.

The long pushrod makes a big difference to minimize wear. After replacing the bushing, and using the long pushrod for quite a few years now, I have zero wiggle, and zero oil leakage.

Is that area an "oil free zone"...................absolutely not. You will always have oil thrown off from the chain, the amount depending on what type of chain oil you use.

 

[SpongeBobbed]

Thanks guys!
I read through a few posts on common leaks so I ended up buying two pushrod seals, a driveshaft seal, and all new gaskets. It's also leaking from the head so I'm going to retorque the head bolts and hope that works (the PO just put gasket maker all around where the heads meet the bottom to stop the leaking .

I didn't end up buying a long push rod when I did my last Mike's order. I should have thought of that. I figured there would be some oil in there from the chain but this is caked on. It looks like someone threw a couple pounds of dirt in there. I did pull the side and sump filter and they look clean so I don't think it got into any of the important parts.

One last question: What are your thoughts on soda blasting a complete engine? It's probably going to take me another 15-20 hours of scrubbing to get the oil off. It would be great if i could just blast this thing clean. Will it hurt the gaskets? Can I blast it with the left cover off to clean where the oil is caked on?

Thanks!