John Deere 726 Snowblower Carburetor Leaking Gas
I have an old John Deere 726 snowblower. I had turned off the gas for the winter so it wouldn't sit in the carburetor and just put fresh gas in and turned the gas on to test it out for the season after changing the oil. After letting it sit for a while I noticed a strong gas smell and found that gas was leaking out the carburetor by the choke (out the opening in the below picture): From Snowblower .
I took apart the carburetor and cleaned it thinking that the pin on the float was sticking and not shutting off the gas flow but another thorough cleaning didn't do it (the carb was very clean to start with). With the bowl off the carb I could manually push the float up and get the gas flow to stop and it flowed nicely with the float down.
After taking apart and putting together a few times I started mucking with the adjustment screw on the bottom of the carb (it was screwed pretty far out to start). I was able to get the snowblower running smooth with the choke on and the screw in quite a ways. This seemed to stop the leaking, but the snowblower wouldn't run with no choke (it idled for about 30 minutes so I thought it would be warm enough).
So, my main question is if there are other ideas on what to do to fix the carb leak and have it adjusted so it runs well.
I also have a couple other questions resulting from this:
1. When putting the carb back together I am not sure if I got the linkage assembled correctly. Below are pictures of how it looks. Does this look right? The main thing I'm questioning is if the spring is in the right spot (now it won't stay on full throttle without being held up which it didn't do previously).
Pic of linkage with throttle all the way down:
Pic of linkage with throttle mid-way:
2. Is the primer missing some parts? See the picture below - I don't see how it would accomplish anything by moving back and forth outside the choke area. Perhaps it forces some air in but I don't see how it would be pulling any fuel into the carburetor.
I did find this sectional from http://jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.HomePageServlet_Alt and it looks like perhaps there should be a gasket (#13), but I'm not sure what good just a gasket would do here either.
Here is a link that might be useful: Pictures