82 GS850 engine will not start

[Guest]

I just finished replacing all the head gaskets, adjusted the valves, new carburator boots (both in and out), and new clutch plates. I tried to start it and it doesn't kick over. The best (or worst) that I got was one loud explosion that scared the daylight out of me. Where should I start to trouble shoot?

[azr]

Often during reassembly people don't get the cam timing correct, especially if it backfires, typical symptom of that issue. This is one idea of multiple of course, but I would start there.

[imgeno2]

I started by checking the plug wires and coils. I cut about 1/2 inch of the plug wire for a clean contact. I then checked the coils and got a good primary reading of 4.2 ohms but the secondaries were open. I guess that I lost both coils at the same time. Is this usual?

[imgeno2]

any suggestions for a good set of coils?

[matt1100]

You replaced the head gasket or valve cover gasket? Are you certain you have the correct wire on the correct plug? Have you tried removing the plug, sticking it in the cap and holding the electrode against the engine case while running the starter to check spark?

Seems unlikely that both coils just up and **** the bed during this other work you were doing. Dyna coils and wires are a good upgrade either way.

[imgeno2]

I changed both head gaskets and the valve cover gasket as well. the plug wires are in the right place but I'm ordering new caps because these are giving me some crazy resistance readings. I havent tried to see if there is spark from the plugs onto the frame but I will try it when the new caps come in. I think that I was getting the wrong procedure for testing the coils. I am getting 4.1 on the primary and 12000 on the secondary when I ohm out the seperate coils. I believe that the coils are good.

[tom203]

I changed both head gaskets and the valve cover gasket as well. .......
I am getting 4.1 on the primary and 12000 on the secondary when I ohm out the seperate coils. I believe that the coils are good.

Your ignition coils are fine- new plug boots are a good idea.
As mentioned, doublecheck your cam to crank timing, it's easy to get stuff 180 degrees out. Note on attached pic , the position of the numbers on cam gears and the notches on cam ends pointing at each other when crank position is at TDC