Tractor Repair: Ford 841 rear main seal replacement, ford service manual, cork screw

Question
Hi, I was wondering if you could help me with replacing a rear main seal on a ford 841 tractor with a 172ci gas engine. This is my Dad's tractor and for some reason my Ford service manual doesn't cover replacing the seal. I have an auto repair shop and I've removed the oil pan. In the morning I plan to remove the rear main bearing cap and replace the seal. I need some tips on removing the old seal which I'm assuming is a rope seal and installing a new style neoprene lip seal. Thanks in advance for your help.
Tom

Answer
Hello,

  According to the parts listing on newholland.com, the gas engine could have either a rope or rubber seal, and doesn't list a serial number break or any other way to tell which you have until you take it apart.  They are interchangeable with each other.  When you remove the rear main bearing cap, the lower half of the seal will be easy to replace, but the upper half will be a little tricky without removing the crankshaft.  If it's a rubber seal, it should come out fairly easy by tapping on one end of it until it moves enough that you can grab the other end and pull it out.  If it's a rope seal, it will be difficult to remove.  There are tool kits available at auto parts stores for removing and installing rope seals.  Instead of driving it out, it will have to be pulled out with an extractor which screws into one end like a cork screw.  Even with the proper tools, it will not be easy to remove.  To install the rubber seal, lubricate it thoroughly and get one end started and roll it in around the crankshaft with the lip facing the flywheel.  The lower half is pretty self explanatory.