Rear engine seal Installation

[Jackie Mac]

I dropped my trans in my 1986 c10 305 v8. while its being rebuilt, I would like to replace the rear engine seal. Could I get some How to Info from you guys? Any Help is much Apprec. Thanks

[jayman68]

86 was right when they changed from the 2 piece seal to the 1 piece seal. To verify which one you have you need to remove, or look thru, the flex plate to see if the end of the crankshaft that you can see is round or oblong(not round). The round one has the 1 piece seal.

[rfmaster]

Originally Posted by Jackie Mac

I dropped my trans in my 1986 c10 305 v8. while its being rebuilt, I would like to replace the rear engine seal. Could I get some How to Info from you guys? Any Help is much Apprec. Thanks

86 was a first year of 1 piece RMS which almost never leak unlike 59-85 2 piece RMS. The 1 piece RMS crank seal can be removed using a flat blade screwdriver - just be careful not to nick crankshaft. The aluminum adapter will have 3 slots where screwdriver blade can be wedged into the old seal. Just work a little bit at time around the perimeter to pry seal out. Note direction of the seal lip when it is removed! Before installing new seal clean crank surface and seal pocket, then use a little bit of oil on seal lip and crank. Also lubricate outer diameter of the seal. FSM calls for J 35621 RMS installation tool, but in its absence I like to use a small piece of 2x4 to gently pound new seal squarely into position until it bottoms out. That's about it - impact wrench makes removal of flexplate bolts an easy job. FSM calls for 75 lbs.Ft torque - I would get new bolts and use a flexplate holding tool (JEGS Performance Products 80530) to torque to correct torque.

//RF

[Jackie Mac]

Thanks Much for all the info. Everything went smooth