My first guess would have been the check ball being stuck as well. Could the return line be clogged?

Nice Panhead.

 

Probably be where I go next. I'll post some more pics later, it's a work in progress, but it is rather cool.

 

Exactly where does the other end of that vent line attach?

And a sub-question: What sort of primary drive is fitted to the bike?

 

See now I didn't know it had a second. Where does it generally hook up? The owner should be here in 30 minutes or so, I'll have to ask him on the primary, because I see no markings.

 

What weight oil do they generally run in these things?
When he gets here we're going to pull the return line and make sure it's not obstructed.

 

50 or 60 weight oil.

The reason I asked is because they don't generally HAVE a vent line, so I was trying to figure out what has been done to the bike and how it's set up. Normally, the crankcase vents out through a passage into the primary drive. The venting gasses help push the oil used to lubricate the front of the primary chain. So I was wondering exactly what the vent line you have is hooked up to. If he has a sealed, later style primary or a belt drive then I'd guess it was just an added vent line.

Here's a couple things you can look for:

Like Dod's mentioned, check for a plugged up return line.

Check the oil pressure relief valve. That would be the other screwed in plug in the oil pump. (That doesn't look like an original Panhead pump, but I'm no Pnahead expert.) If that's weak or stuck open it could be allowing too much excess oil to flow into the bypass passages. That would make it come out the old primary lube / crankcase vent passage, or new vent tube if that's what's been added.

Look for a screw in screen "filter" in the crankcase just forward of the oil pump. It may be where he's got the oil pressure guage installed, but it's hard to tell. Pull that out and make sure nothing is clogged up in there. If the screen is blocked that will increase pressure in the passage back to the oil pressure relief valve.

Take off the outer cover on the oil pump and turn the engine over by hand to make sure the gears in the pump are working. (They use a key on the pump shaft to work.) The return / scavenger gears are the ones furthest out from the motor, and the oil feed gears are the ones on the inside, closest to the motor. If the key is sheared the scavenge gears wouldn't pump and the oil could be just backing up inside the timing gear case.

 

S&S pump, no return at all. We spoke with S&S, looks like we're pulling the pump.

 

Well, he just talked to the Indie and he talked him into taking it back. Claims he'll get right on it. I don't understand why, he had it 6 months the first time.
I'll post up what's wrong with it after it gets repaired.

 

Well, if you're getting no return pressure at all I'd guess it was a problem with the scavenger gears. (Maybe a blown gasket between the feed and scavenger gears?) I'm not familiar with the S&S pumps but from the picture you posted it looks like it's plumbed like a Shovelhead pump. Be interested to learn what the problem was, but if it takes 6 more months I'll have forgotten what the symptoms were. :biggrin:

 

His reasoning was that it would take us too long to get the parts.
My exact words were "But I bet it doesn't take us 6 months to fix the sob."

He assumed it was a sumping problem and I'd be able to get him on the road quick. He knows I'll give him **** if they don't get right on it like was promised.

 

News is the pump is fried. I'm trying to get my hands on this thing so I can see what makes it tick. It's kinda embarrassing how little I know about this type of oiling system.

BTW, Eye it has a belt drive primary on it if that's what you were asking.

 

Yeapers. If it has a belt drive primary, that means that the primary lubrication oil feed has been shut off or diverted. And that would have given me a clue as to how the bike was plumbed for oil, so I could have at least had a hope of knowing where to start from. :biggrin:

 

See now, my being a car guy, you wanting to know what kinda drive it had seemed like some type of senile rambling. :coffeescreen:

The only dealings I've ever had with dry sump engines was on our MX bikes and they never had an oiling problems so I never had to work on them.

 

It can be hard to tell the difference between my normal senile ramblings and the actual legitimate questions.

 

We have that in common.

 

The bikes up and running again, pump fixed it.
Now I just need to get myself schooled on Harley dry-sump systems.

 

Regular old factory service manuals have a great explanation of how the oil system works, complete with diagrams. Maybe you know someone that will loan you one for a bit. The library here has a few of them too. I don't know if a Haynes or Chilton Harley manual has the explanation and diagrams though.

The dry sump system works substantially the same for most Big Twin models over the last 60 years or so, but there are some differences in different models. Different types of oil pumps, different oil routing, and so on.

 

Well I found a video where the dude does a decent job of explaining the pump and now I feel stupid!! I just wasn't making the connection that this pump has both pressurization impeller sets and return sets.

Sometimes the mind can make something so simple seem so difficult.

 

I run into that all the time working on old farm equipment ODE. Seems we are programmed to over think things. Sorta sucks sometimes when in my case some old farmer comes by and shows me something that was so absolutely simple. You feel so dumb.

 

same in my profession sometimes we overlook the obvious

 

Old Harleys also have a timed breather that draws oil into the engine. When the pistons are on a downward stroke, the breather is open and vents crankcase. When the pistons are on an upward stroke, the breather is closed, creating a vacuum that draws in oil.