Biri asla öğrenmek için fazla yaşlı. -"One(someone) is never too old to learn." 

I had thought to use -çok initially but none of it´s uses seem to fit in with "excessiveness" which  is how "too" is being used here. My instinct to use "-mek için" simply because I was not sure how to tie the excessive adjective in with the verb. Another example:

"The kitten is too small to jump up on(to) the bed."

Where you have the excessive adjective (too small), followed by verb infinitive (to jump) Though I know how -mek için is supposed to be used

Biri öğrenmek için asla yaşlı değil.

Think"asla" here as "ever" not "never". So we need to make sentence negative with "değil".

Mavili, I think it was a good idea from you to see that excessiveness actually is written into the -mek için structure without adding anything else.

Separating ´too much, too expensive, too short´ from ´very much, very expensive, very short´ is an interesting question. çok is so wide spread it´s difficult to sort out its many meanings sometimes. (It´s funny that I have the same problem in Arabic even though it is difficult to imagine an influence of any kind in a matter like this.)

Anyway, there was a useful discussion about it here:

http://www.turkishclass.com/forumTitle_51414

Thank you Gokuyum and Abla. To see that my instinct to use -mek için was correct is a nice feeling. After I posted I had wondered if there was something else I missed on that context. And yes I should have done a search of the site first.  I do understand that degil to make the sentence negative makes more sense. I had presumed incorrectly that just having -asla would do that.

I do wonder though, if you remove fazla, what is it that gives -yaşlı an excessive sense? 

Abla are you also learning Arabic? Thats so cool! Is there a similar expression in Arabic grammar?I agree, its very streamlined for that meaning all to be wrapped up in -mek için.. Not only showing its versatility, but also allowing for an efficient way to convey a point just as with many other aspects of Turkish grammar. 

No, I am not learning Arabic, Mavili (and it is not cool).

I guess the similarities between Turkish and Arabic are more in the vocabulary, hardly in the grammar, even though some Arabicisms were forced into Turkish syntax in the Ottoman language. While Turkish adds grammatical markings to the end of the word, in Arabic the word stem itself is often subject to changes.

But sometimes you notice strange similarities. They may be mutual influence or they may be accidental.

Ah right, I think I remember from when I started trying to learn Arabic, about how the meaning of the word changes with placement of the hamsa or something, and how the stem can change gender specifically.

It was interesting to read about how some of the adopted Arabic words that end in different letters affect vowel harmony in the Turkish word. (Lewis, 18.)

The influence is certainly there, and I like for example how from the Arabic word ´waqt´, vakit was made, this must be why in Turkish the sounds of V and W are pretty much interchangeble.