Greetings,

 I just started working on my 1972 AT2 and I have some questions that I hope you all can help me with. I have worked on other bikes a little but this is the first time working on this bike. The bike has been sitting in my garage for the past 20 years and now I finally have the time and place to get it going again. 

I have included a few images that I hope helps. The first is a pic of the carb for reference. then the main nozzle, then the banjo bolt/float bowl.  

I pulled the carburetor and got it cleaned up. While putting it back together, I noticed two thing I have questions about. First, is the main nozzle. Is the black band around the nozzle the o-ring (part number 214-14147-00)? My assumption is yes but I would like confirmation.

Second, is the banjo bolt that screws into the float bowl. After checking the parts diagram, I noticed that it was missing the gasket. I got the gasket and noticed that when I screw the banjo bolt into the bowl, the holes in the bolt do not line up with the holes in the bowl. Does this matter? I made a little shim washer that when included with the gasket, the holes do line up.  

Any advice would be greatly appreciated.

Thanks

 
 
 
 
 

Yes, that is the critical o-ring

No, the holes do not need to line up.

Thanks MarkT

That was my thought as well. If fuel can seep out everywhere when you don't want it to it can surely get around that bore. I had wondered if that o ring needs to also make contact with the cavity in the bowl. Yours looks fairly flat and that cavity can get larger over time due to electrolysis. 
 

Thanks adguy2112.

The o-ring in the picture is original and was hard as a rock and flat. When the nozzle was in the cavity, there was a bit of slop. The local Yamaha shop had a new o-ring and after fitting it on, the nozzle fits tight in the cavity. Hopefully the carb is ready to go now.

I found another issue today that maybe you can advise me on. When I took the exhaust off, there was several ounces of oil in the neck. It looked like gear oil. Also as I work the kick start and the piston went up, it looks like there is a fair amount of oil below the rings. I have done some research and it seems like I need to replace the crank seal on the right side. Does that sound correct?

Thanks

Oil in the pipe does not necessarily come from the transmission through the right side seal. Could be leaking through the check ball in the oil pump. But replacing the seal is never a bad idea.

I agree with Mothersbaugh.  Very likely two stroke oil that slowly leaked into crankcase.

You'll need to drain as much as you can out or it will be very difficult to start and/or the hydraulic pressure may blow a seal out when kicking it over.

Sorry, but I am pretty new to this. I have drained the transmission oil but I am not sure how to drain the 2-stroke oil from below the piston.

It's not a normal situation.  Are you replacing the crank seal?  If so, after you remove the old seal lay the bike over on its side and let the oil run out through the bearing. 

If not replacing the seal, there are other ways.

 I'd just push it around in as lower a gear "fast spinning" as you can handle. Plug out, exhaust off & you'll get rid of enough to run it up. Going to make a bit of a mess out the plug hole & exhaust outlet. Wouldn't worry if only a small amount in the crankcase, just start it up but keep the revs low but little bursts up & down till she's ready to go for a ride. Exhaust is on when ready to start it. Just empty out the header first.

Also if it 'is' the pump gravity dripping into the motor over time, then there's likely fluff or something under or around the ball & spring at the union on the pump where the line runs up to the cylinder. No8 & 9.
www.partzilla.com/catalog/yamaha/motorcycle/1972/at2/oil-pump