Suzuki 2 Strokes

I have a 1976 gt500 I bought, 1st kick runner. Trying to get it sorted out. Everything is fine but the lines aren't filling on the left bank beyond the part where it goes 1 into 2 lines. The right side works fine. I took off the left side, blew on them with my mouth to make sure they were clear ( I read about the check valves) Started it up and it filled with oil then after 30 seconds the 2 lines went empty again. I have it in neutral, the right side seems spot on, the left side works to where it goes 1 into 2. Filled up initally then went enpty again. Looks like oil is trying to move but can't. Put it in water and again blew on the oil pump end and didn't see any leaks. The line itself looks good. banjos are nylon and tight. Is the pump one chamber or can one side pump and not the other? Any suggestions?

Take a hand oil can and try to push oil into the hole that the banjo bolts into. It may be partially blocked. Also make sure that with a mityvac or something similar that you can blow from the pump towards the motor but NOT in the reverse direction.

It's supposed to be a one way valve - a hydraulic diode if you will.

I hope you didnt damage the spring check valve by blowing through it. The springs are very fragile. You can check the check ball and springs by taking the banjo carefully apart. search the site and you should find instructions and photos on how to do it.

I was carefull just using my lung power to blow to see if they were clear. I did fill the line all the way up , kept oil to the 1 to 2 portion but air from there on. I can't find any disassmbly procedure. can some one point me in the right direction? The reason I'm not leaning towards the check valve is the oil pump I believe is a positive dispacemet pump and should at least pump up to the banjo.

the oil pump I believe is a positive dispacemet pump

Yes it is...but in a very loose sense. These pumps have a certain amount of internal clearance when new......and don't get tighter with age. There is a chance that yours MIGHT be beyond redemption. This can happen if grit gets into the pump and scores things up.
Dismantlement and inspection may be in order....

I figure out how to check the valves once I got them off, one is bad. I can't see how to take them apart. I posted in the wanted sections for one.

Well, a member was good enough to send me some check valves. I replaced the one on the line that wasn't pumping and still nothing. I took liquid electrical tape and covered all the joints in the 1 to 2 block and at the fitting. Success. I don't know where it was leaking and don't care, it is pumping oil to all lines. Took her for a 10 mile ride today and can't believe how smooth it is. I mean no vibration like I remember on my t500. And it gets. Everthing works. New tires and I'll be cruising.