Jesus does know the time of the second coming - he says it will be within the lifetime of the Disciples. He does not say exactly when though. It is not because He does not know, it is because, the way hHe phrased it, requires all Christians to be prepared - i.e. to lead a constantly Godly life.
I definitely think that Jesus, as an apocalyptic figure, did think he was going to return in the lifetime of the disciples ("this generation will not pass away...Matt 24:34). However, Mark 13:32 and Matthew 24:36 is specific as to not knowing the day or hour. So although Jesus taught the imminence of his second coming, he clearly plead ignorance to the exact timing of his second coming especially since these texts say that the father alone knows. My argument is that if Jesus plead ignorance to this knowledge, then he can't be God (1 John 3:20).
Your second thought that 1+1+1 = 1 is based upon what is known as "The Johannine Comma". John:5:7-8
The King James Version, which was based upon these editions, gives the following translation:
For there are three that bear record [in heaven, the Father, the Word, and the Holy Ghost: and these three are one. 8 And there are three that bear witness in earth], the Spirit, and the water, and the blood: and these three agree in one.
The red text is an error. The story can be found at http://www.bible-researcher.com/comma.html The words should not appear in the Bible. IIRC, Jehovah's Witnesses ignore this and are not Trinitarians, however, they are probably closer to real scripture than all sects who accept it.
I did mention the Johannine Comma in my reply #15. I'm really curious how bluecolour is going to respond to this. Thanks for the link! I hope bluecolour reads it.