Topic: Help locating oil leak on bottom of cb550 (not from oil pump/shifter/sprocket)

[RFogelsong]

I'm having a bit of trouble locating a recent leak on my '75 550k.  It's leaking like 4-5 drips every time it's parked more than 24 hours.  I haven't had anything around there loose recently and the last oil change was 2 months ago.  Basically, I don't know what triggered this to just happen now.   

From what I can see, it's coming off of the bottom of a 14mm bolt (it's on the underside of the motor) between the stator cover and the starter mount/sprocket side cover (as far as a front to back location goes) and under the (rider's) left hand side of the engine right there around the oil drain plug.  It's about 5-10 mm higher than the oil drain plug though.

From the head of this bolt it drips onto the frame rail and then on down to the floor.  This isn't blowing onto this bolt from anywhere because I wiped it all down and haven't ridden it since then.  I retorqued the bolt and it didn't seem to change anything.



SO, Do I have the right bolt or is it tracing down from somewhere else?  Thanks for any help. 

[w1sa]

Chain oil...??

[Hasenkopf]

 pull  the stater motor and check the seal in the starter motor support or  the o ring on the motor housing.

[harisuluv]

I know the general vicinity of what you are talking about.  A picture would be helpful though.  If the only thing that has changed in the past two months was the oil change, I would start there first.  Could be your oil filter gasket or your drain plug.  I have a very slow leak after changing my drain plug and the crush washer has just been "crushed" one too many times.

[cabrala]

RF, I attached a picture of my own 550 but of the area I think you are talking about. The bolt called out by the red line is an oil gallery, I believe. It has also been told to me to be a place where some oil can drip down as there is a o-ring there. I hope this gives you a bit of direction, but also please throw up some pictures so all can get a good look.

[Dimitri13]

That's an oil passage cap. There's an o-ring for it. Check your fiche.

[bryanj]

It's also the lowest point on the engine so oil from anywhere will gravitate to there before it drips off

[cabrala]

Wouldn't the sump pan be the lowest point on the engine? In my case I had oil dripping down the pan, along the finned bottom and off the center stand. I agree that this particular leak could be coming from higher up, as gravity tends to make a mess of things but the oil passage cover (nut?) is also a very good place to start tracing.

None of us can even say for sure that the picture I put up is accurate to RF's situation until he verifies it and throws up some of his own pics. Have you searched for the powder trick?

[Shane72]

I have used the following old trick to locate leaks--very effective!

1.  Start with a clean and dry surface.

2.  Spray a nice coating of athlete's foot powder over entire area.

3.  Any leaks will soon be obvious at their point of origin.

4.  Wash off the powder and address leaks.


All the best,

Shane

[RFogelsong]

Thanks guys, that picture is the exact bolt I was talking about, sorry I couldn't provide a picture, my camera isn't working at the moment.  I backed the bolt off a thread and re-torqued it.  Leak gone.  I just couldn't quite figure it out myself because I knew it wasn't any of the usual suspects for a 550 (under the side cover and around the oil filter is clean. 

SOHC4 forum to the rescue again.