wont start, probably something simple, i hope!

[ramps]

Hello all, my mate has a mk1 8v gti and it doesn't want to start up, he was having problems with it turning over slowly and lazily but then starting. Once warm the car started normally. This happened a couple of times, intermitantly, before completely refusing to start. He decided that it was the starter motor so sourced a second hand one, it still doesnt start but makes a repetitive clicking noise as if the solenoid on the new one is at fault. The seller asured him it was woking fine when it was sold.
 So, my mk1 bothers, any ideas?

[SoundillusioN]

was it turning over before you changed the starter motor, also does the new starter motor turn over?

[ramps]

no it stopp turning over on the old one but would bump start, then would start normally once warm. Havnt bumpped it with new one though

[raferackstraw]

check ignition switch, waggle key while turning and see if it starts, also check main earth to g/box and check and clean terminals on cables to starter