Chain case oil mistake

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Before digging into the seal between the inner chaincase and engine, I'd make sure if you do or do not have a leak from the engine into the chaincase. What I'd do is take off the outer chaincase cover, clean up the innards, put it back together and install the correct amount of oil, it's not much and keep an eye on it. If it keeps going over the level hole, you know it's leaking from the engine into the chaincase. Then it's time to remove the inner chaincase. Sometimes those 3 bolts that hold the inner case bolt to the engine leak too. I used studs and nuts and locktighted the studs in the engine. It also makes it easier to get the inner cover on, but you have to grind down one of the nuts for the chain to clear. Those 3 bolts are sketchy at best in my opinion for what they do.

The shaft from the clutch to the chaincase can leak from the gearbox too, there's a simple seal for that. But it would also mess with the clutch.

Too much pressure in the engine can blow oil out that seal too, make sure your breather is working right.

Good luck with it all. You'll figure it out.
 
For posterity.. the width of the small and large chain case cap screw size, if anyone is looking for the right size washer or whatever to do the job.
 

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DogT said:
Before digging into the seal between the inner chaincase and engine, I'd make sure if you do or do not have a leak from the engine into the chaincase. What I'd do is take off the outer chaincase cover, clean up the innards, put it back together and install the correct amount of oil, it's not much and keep an eye on it. If it keeps going over the level hole, you know it's leaking from the engine into the chaincase. Then it's time to remove the inner chaincase. Sometimes those 3 bolts that hold the inner case bolt to the engine leak too. I used studs and nuts and locktighted the studs in the engine. It also makes it easier to get the inner cover on, but you have to grind down one of the nuts for the chain to clear. Those 3 bolts are sketchy at best in my opinion for what they do.

The shaft from the clutch to the chaincase can leak from the gearbox too, there's a simple seal for that. But it would also mess with the clutch.

Too much pressure in the engine can blow oil out that seal too, make sure your breather is working right.

Good luck with it all. You'll figure it out.
Click to expand...
This is super helpful, thank you. When taking off the chain case cover, are there are lessons from experience worth knowing? Does anything else want to fall out or come apart other than the fluid and the case gasket/seal? Does the clutch assembly stay put?

I'm going to go ahead and drain it, clean it up, and go through this process to see if it was an anomaly from the bike sitting for so many years and then being overfilled with oil, or if I have a seal problem on my hands.

Best I can tell all the rubber on the bike from the tires to the little bits is at least 10 years old. I'm having to replace a lot of dry rot.
 
Nortorious said:
This is super helpful, thank you. When taking off the chain case cover, are there are lessons from experience worth knowing? Does anything else want to fall out or come apart other than the fluid and the case gasket/seal? Does the clutch assembly stay put?
Click to expand...
You'll need to remove the left foot rest. You can let it hang on the cable. Bike on center stand with a pan under the primary, remove the center nut (3/4"). Crack the primary cover seal - a flat blade like a putty knife against the outer cover edge will separate them. The cover is also located with 2 dowels. Once the bottom is open all the oil will come out and you can remove the outer cover. It's a messy job. Everything inside stays put. The big O-ring usually stays in its groove in the inner chain case. Rags followed by your favorite cleaner spray.
 
elefantrider said:
Do not overtorque the center cover bolt.
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Multiple sources have given me a grave warning to not over torque the center hex bolt on the chain case (among other grave warnings about the head bolts, grease nipple, etc). Anyway, the two manuals I have don't reference a torque for this bolt.

Is there a source that lists the correct torque for the chain case center bolt, or is this something one has to learn to feel?

In general I'd love any suggestions on a good source for torques. I haven't found a central reference yet, just occasionally listed in some sections of the shop manual. Thanks!
 
Nortorious said:
Multiple sources have given me a grave warning to not over torque the center hex bolt on the chain case (among other grave warnings about the head bolts, grease nipple, etc). Anyway, the two manuals I have don't reference a torque for this bolt.

Is there a source that lists the correct torque for the chain case center bolt, or is this something one has to learn to feel?

In general I'd love any suggestions on a good source for torques. I haven't found a central reference yet, just occasionally listed in some sections of the shop manual. Thanks!
Click to expand...
OldBritts site, Norton Torque Specs:

 
I found a tool that is shaped almost like the Isle of Man symbol that has 3 different sized shaped half moon that works great. The only problem is I can't remember where I got it.
 
I just remembered that there is also a tool that one uses with a three-eights in drive ratchet specifically for those larger caps.
 
richmont said:
I found a tool that is shaped almost like the Isle of Man symbol that has 3 different sized shaped half moon that works great. The only problem is I can't remember where I got it.
Click to expand...
Thanks! It may be this one that @MichaelB pointed out ft Motion Pro, or something similar. I ended up grabbing this since it's available cheap and locally. If it's not ideal, there is the "official" tool I can get on my next Andover order from over the pond.

On my search for a tool a lot of plumbers' tools came up. I'm optimistic about the Motion Pro.

Timing Plug Wrench - Motion Pro

Motion Pro - High quality cables, tools and controls for motorcycles, ATVs, snowmobiles and personal watercraft.
www.motionpro.com www.motionpro.com
 
The chaincase outer cover is a 'press fit' with the central 'bolt' which is actually a 'Nolt', a bolt and nut combo, once your remove it you'll see. It has internal threads like a wheel nut. Reason not to over tighten it is because it will warp the cover which as you can see is rather large and only fixed by that one 'bolt'. If it's too tight it will warp and leak. Other thing needs to be done if you can't get the chaincase to stop leaking is correctly shim the inner chaincase cover from the service manual. Involves taking off the clutch and all, like installing the engine seal. What the proceedure does is make sure the inner case is flush with the engine and also the other attached parts to keep the inner case straight. A carpenters square against the inner cover's surface will usually tell you if it's OK or not without breaking it down.

Your bike from the pics looks so clean I doubt if you have all these problems. It's probably just a matter of renewing the seals/oil levels etc.
 
DogT said:
Your bike from the pics looks so clean I doubt if you have all these problems. It's probably just a matter of renewing the seals/oil levels etc
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The bike definitely had some thoughtful previous owners so it's been my philosophy to be conservative. It hasn't been started or worked on in 6+ years, with many bits needing maintenance but I'm generally trying to get it to safe running condition while learning about it and trying not to break good work done by the PO.
 
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