Can too much oil in the counterbalance shaft be damaging? 951 (Carb) engine

[bkwashby]

I filled the counterbalance reservoir to the bottom of the fill hole and have been running it for over a month before reading it should only be 40ml; so there's probably about 80ml in there. Can this damage the engine?

 

[Sportster-2001-951C-Stock]

You should be okay, it's kind of hard to overfill enough to displace all the air due to the air space around the crankshaft gear, air will be trapped there. Some air space is necessary b/c the oil will expand as it heats.

After running for over a month, can you still see some oil? I expect it will be lower than the fill hole due to some oil has moved away into the crankshaft gear area, this is normal, it doesn't mean the oil has leaked out unless you cannot see the oil below the fill hole then add some until you can verify there's definitely oil in there.

I check mine beginning of every season and top it up if I can't see oil, this way I know for sure there's always some there.

Keep an eye on the level if you think the reservoir is leaking, the gears must always run in an oil bath.

 

[bkwashby]

You should be okay, it's kind of hard to overfill enough to displace all the air due to the air space around the crankshaft gear, air will be trapped there. Some air space is necessary b/c the oil will expand as it heats.

After running for over a month, can you still see some oil? I expect it will be lower than the fill hole due to some oil has moved away into the crankshaft gear area, this is normal, it doesn't mean the oil has leaked out unless you cannot see the oil below the fill hole then add some until you can verify there's definitely oil in there.

I check mine beginning of every season and top it up if I can't see oil, this way I know for sure there's always some there.

Keep an eye on the level if you think the reservoir is leaking, the gears must always run in an oil bath.

The only reason I'm asking is cause at around 2500 RPM after its been running for more then 15min I hear a grinding noise. Kinda sounds like a bad bearing. Wondering if I screwed something or if it's just a bearing in the engine going on it's own. Pump is rebuilt and new carbon seal so engine bearing my only guess.

 

[Sportster-2001-951C-Stock]

Lots of things can happen, occasionally in some sequence but not always. Sometimes problems can be traced to recent maintenance such as a failed pump rebuild or the new carbon seal might be vibrating.

If you sample the counterbalance oil and discover "sparklies" I would just tear it down or send it in for reman as opposed to destroying a rebuildable core.

Something may have happened unrelated to counterbalance oil such as the crank bearings may have been rusted at some point or the incorrect 2T oil was used, hard to know the history or sequence of events.