Topic: Cleaning/Clearing Oil Gallerys and Jets- How?

[ncstatecamp]

Ok so before I put everything back together I want to make sure all the oil jets and gallerys (galleys?) are clear and free of any crude. I must be an idiot though b.c I cant for the life of me figure out whats pumping into where. I get the jet that the under the cam holders shoots into the cam holders and spreads out though all the tiny holes, but wheres the supply for the jets come from? Ive looked at this diagram but its a generalization and im just not seein it...

http://farm3.staticflickr.com/2137/1894867089_244ff4b884.jpg

also from this picture it looks like oil is dripping back down to the pan through the valves to the top of the piston head? yeah that makes no sense to me as itd just be burned...

So where do I need to blow air through and clear out. I have everything above the case apart.

[70CB750]

Supply for the jets comes up along two engine studs next to the cam chain shaft.

If you have it apart it is not hard to see.

[ncstatecamp]

Ah ok that makes sense now. So where the 2 square holes on the crank case are mate up? Best way to clean that? just a bottle brush up in there and....?

[flybox1]

a good thread with a diagram.
http://forums.sohc4.net/index.php?topic=37846.0

[ncstatecamp]

ah ha that last explanation is what I was looking for. Thanks man. The diagram you mentions is the one I found, its just kinda vague.

Hi Mystic_1,
  Thanks for the info. I have a couple of questions though:
1. In your statement: "oil travels upwards from the main oil gallery via the two center rear cylinder studs, all the way up to the head". Does the oil enter the head (valve area) via the orifices, the cylinder studs, or both?

2. I have what looks like 4 orifices. The two in the middle have holes in them but the two outer ones do not have holes in them. Is this normal? There are 4 holes in the part that mounts over the orifices as if something is suppose to flow from the orifice to the rocker arms/cam holder above all 4 orifices, but only 2 have holes that would allow oil to flow. Is this correct (only 2 have holes) or not?

Thanks,
Bill

1. Both:  Oil travels up through the passages that the studs sit in.  They then pass sideways through a small drilled hole to the oil orifice.  From there the oil passes upwards into the cam holder.  The cam holder has interior passages that direct the oil to the bearings and squirt onto the cam lobes.

2. There are only two orifices, on the "inside" ends of the cam holders.  If you look closely at the diagram, pressurized feed oil path ends at the outer ends of the cam holders.

mystic_1

for later reading if anybody stumbles across this thread with the same question.