Topic: Name that leak!

[CBNJ74]

Patient: 1973 CB750K

Location: Left underside near side stand. Circular piece with a wire attached held in place by a Phillips head screw.

What type of leak is it and how do I stop it?

[Davez134]

That's your neutral switch. if the leak is coming from where the screw holds on the wite you may need to replace the switch. if it is coming from around the outside of it, there is an o-ring in there that can be replaced.

[CBNJ74]

I suspect this o ring cannot br replaced till my next oil change?

[Davez134]

That's up to you, depending on how long it is to your oil change and how long you want to wait.  Good portion of your oil should still be in oil tank. You can put a drain pan underneath it, see how much oil comes out, add about that much back in afterward and adjust oil level once bike is at operating temp.  Or just wait haha.

[CBNJ74]

I'm going to try replacing the O-ring first. I hope the switch doesn't have to be replaced because that's around 100 bones. Do you think the o-ring is a standard size that I can pick up at hardware store or will need to order the genuine article?

[Xnavylfr]

If you have a way to lean your bike over toward the RIGHT side, say against a wall, let it sit for a short while (30mins) and 99% of the oil that's left in the engine will run to the right side of the engine and you'll have very LITTLE come out when you remove the switch.


Xnavylfr(CHUCK)

[Davez134]

I'm going to try replacing the O-ring first. I hope the switch doesn't have to be replaced because that's around 100 bones. Do you think the o-ring is a standard size that I can pick up at hardware store or will need to order the genuine article?

Look online at a parts fiche. ( I usually use bike bandit.com as a reference) sometimes they give a size in description) or take it out and go compare. I've also heard applying light coat of vacuum grease to I ring when installing can help prevent further leaks, but haven't used myself.

[Johnie]

There is some other posts on here about how to install that new O ring without damaging it. It has been a while since I did mine, but if I recall correctly it was to slide the ring on the switch and then slide the unit into the recess. In other words, do not put the O ring in the recess and try to slide the switch into it. It is a snug fit and I would suggest a OEM O ring.

[Xnavylfr]

The PROPER way to install a new O ring is with some grease on it. it also helps it slide in the hole and not cut the sides.If you have to slide the O Ring over some threads to get to it's groove, wrap the threads with some masking tape and then slide the O Ring over the tape down in to it's groove. This prevents the ring from damage on the threads!

I spent 20+ years in the US Navy as a Aviation HYDRAULICS Mech. I've replaced many O Rings..


Xnavylfr(CHUCK)