mattd860 162 #1 Posted August 12, 2011 I'm looking at buying a 1990 520h (Onan 20hp) with a slight oil leak behind the PTO. How hard is it to get in there and replace that seal? Share this post Link to post Share on other sites
stevebo-(Moderator) 8,538 #2 Posted August 12, 2011 Will (Truckin88) can chime in as he has done it on an onan. Share this post Link to post Share on other sites
Kelly 1,033 #3 Posted August 13, 2011 There is a soft plug there too, mine leaked, I cleaned it good and put a lite smear of RTV on it, so far so good, I know it's not right but worked. Share this post Link to post Share on other sites
mattd860 162 #4 Posted August 13, 2011 Maybe I'm missing something but it looks like the bearing plate can be removed without even removeing the motor from the tractor. This will allow me to replace the seal. Thoughts? Page 35-5 on this link (Onan Manual) explains what I think needs to be replaced. Share this post Link to post Share on other sites
Shuboxlover 481 #5 Posted August 13, 2011 Other than the fact Onan wants a MINT for their seals/gaskets.... :D Share this post Link to post Share on other sites
TT-(Moderator) 1,162 #6 Posted August 13, 2011 Other than the fact Onan wants a MINT for their seals/gaskets.... A link that may change your mind. Share this post Link to post Share on other sites
dennist 139 #7 Posted August 13, 2011 Other than the fact Onan wants a MINT for their seals/gaskets.... A link that may change your mind. Wow that is reasonable. Maybe something to pick up just in case,for that kind of money. Share this post Link to post Share on other sites
shorts 182 #8 Posted August 13, 2011 Try using an icepick to punch a couple of holes in the metal outer part of the seal and then put in a sheel metal screw to pull the seal. I have an adapter that i use on a slide hammer that works real slick. punch several holes before you start so that if you strip one out you don't end up driving the seal back inti the cover trying to punch another hole. once you get the seal out past flush with the cover use a hammer and chisel to distort the seal od and it should pop right out. CAUTION be very careful not to damage the surface of the crankshaft. Share this post Link to post Share on other sites