1991 Lexus LS400 Won't Start

[johnqz]

Hi,
I'm new here.
I have a 1991 Lexus LS400 that won't start after replacing the starter.
Say more about the car: the starter stopped working in Jan. 2009 because of the contact points are worn. BTW, it has 142,000 miles on it.
The car was parked at a open space and it was too cold to work on changing a starter for a LS400. Not sure if you know how much pain to take to get the job done.
As I turn the ignition on, the starter will spin because you can see the cooling fan is turning and so is the timing belt (moving). But the problem is 1) it won't start; 2) I can hear the starter spinning but not cranking.
I checked the plugs. Most of them are dirty so I cleaned them. They were wet too maybe because of the fuel dumped in the cylinders as I tried to start the car. So I removed the injection fuse. Still, not luck.
I'm going to check the diagnosis code tomorrow see if any error code comes up.
Any suggestions and hints are welcome. I am stuck here.
Thanks in advance.