https://blockchain.info/q/pubkeyaddr/1Fy8dvuHjiTL.....
- read more about compressed and uncompressed here: https://bitcoin.stackexchange.com/questions/3059/what-is-a-compressed-bitcoin-key
- use this tool to count characters faster http://string-functions.com/length.aspx
Yes, i have spent from that address before. Actually, the key is a 130 characters as you said, and it goes as follows "04980461a19399593793b7394b26d4bf0af855b60406591ac8312....."
so it is as i suspected. a bug in blockchain.info!
you imported your private key a long time ago and that private key was an uncompressed private key (started with 5) and now blockchain.info has converted that into a compressed private key (starting with K). that is why the public key and the base58 (or bitcoin address you've got = 1Emhxm...) is different.
now all you need to do is to convert that compressed key to the uncompressed one.
to do that, the only trusted tool that i know is https://github.com/pointbiz/bitaddress.org
you can see the live version here: https://www.bitaddress.org
although you MUST take a copy of the project and run it offline for security reasons.
open it, then get rid of the address generation step (move your mouse around until it shows 100% complete.
then go to the wallet detail tab and paste in your private key (KyF21...) and click View details button.
scroll down and find the private key which is starting with 5 and copy that in electrum
edit: a picture help:
https://i.imgur.com/Jem65wZ.jpg
thanks alot