Grumpy_Mike:
sendval[i]=analogRead(i);Reads a different analogue input each time. If you are using a 4051 you want to read the same analogue input because the 4051 has only one output.
As written the code assumes that you have three 4051 chips attached each to a different analogue input. Then you are reading the value from input 0 from the first chip, then input 1 from the second chip and input 2 from the third chip. Unless you have post attached to these inputs you will read floating values and get the sort of results you are seeing.
I don't think that is your setup.Also why so much white space (blank lines) it makes the code hard to read.
No I'm having only one 4051 connected with 3 pots connected to it.
Edit: I forgot to mention that I get funny readings when one of the pots is at the very right (reading 127). It gets stable after a while, is it because of multiple pots + 4051 connected to same source (arduino +5)?