I bought a 86 fourtrax 350 that the seller said it just needed a cdi box but i bought a cdi box and a coil and it still wont get spark. What else could i try?

 

Always check the wiring to the CDI before replacing one. That way you know what is wrong and, even if it is a faulty CDI, if the earth to it is bad, it will blow your new one. It is best to get a workshop manual which tells you the tests required, as I'm not sure if the old 350D had standard AC CDI ignition, the contemporary 300 didn't, but the 250 did.