Truck Repair: valve lash, tdc mark, vavle

Question
thank you for reading this. an acquaintance of mine also owns an '01 isb like i do. when his had 65,000 miles on it he took it to the dealer and had them run the valves. he swore it was a great thing to have done. i was wondering if there was any truth to this, and if so where can i get free instruction about performing this myself.(don't want to buy a book). i am knowledgeable in mechancal abilities. i just don't have any money. thank you very much for your time. my truck has 72,000 miles on it now.  

Answer
If you have a Cummins maintainance manual,it is in there.The intake valve lash is 0.010 & the exhaust is 0.020.I dont know excatly how for memory,I use a chart I made up.I can tell you that you adjust 1/2 the vavles,turn engine 360 degress(one full turn)& adjust the rest of them.You will need a 5mm allen wrench & a 14mm boxend wrench to adjust valves after you getthe rocker cover off.Simply put,you trun engine on top dead center #1 adjust both valves on #1,then even # cyls are one vavle(int) & odd #s are the other vavle(ex).Turn engine one full revolution and adjust the rest plus both #6 valves,meaning if you adjusted #2 intake,you will adjust the exhaust this time.Dont take my word on the descrition,You will know if #2 intake or exh valve is loose to do the even/odd thing,I just cant remeber it to tell you excatly which ones on what cyls.If you take that oil fill off the frt cover there is a TDC mark(line) on the fuel pump gear & TDC line on frt cover,but when you turn it one revolution,it will be 180 degrees out(pointed down)for #6 TDC.