I am having problems with the starter... I put in a new starter and it will not engage with the fly wheel at first it was blowing the eec fuse got that fixed and its not being blown any longer but the starter still will not engage I took it out and went and had it tested and they told me it was fine. I have no clue what it can be can you please help...

before all these problems started that vehical was driving fine my boyfriend changed the starter fluid it started up but the car would not move then the next day it started blowing the eec or ecc fuse after that got fixed now the starter does not engage with the fly wheel its been taken down and put back as to maybe it was put in wrong and still the same problem tell me something does these vehical requiere the starter to have a shim on the starter it did not have one when I took the bad one out but the vehical was not mine and don't know if it had to have one.