Hello folks, I am new here and this may have already been covered but if it can help anyone then that will be good. I have a 1979 B7100D with an ALPS B219 loader. I wanted to change the fan belt and had to get those nasty double roller chains off of the front of the crankshaft and the hydraulic pump. Well with a little luck and some time invested I did get both off ok. I read on this site or another site that the double roller chain was still available from Kubota for about $40.00 Also the belt was still available for around $10.00. Well I went to my local NAPA and got a Gates XL7300 belt in stock for about $10.00 so that was ok. Then I went to a local bearing and conveyer supply and found that a Martin # 4012CHN is the exact double roller chain and it comes with a master link for $15.00 each in stock. I hope this may help someone save a little money. Thanks for reading.