I have a question about oil seals and hydraulic system seals. Do additives work and are they safe to use? My p218 had a lot of leaks when I first got it and with great help from Boomer I did a decarbon and replaced all the gaskets but I think the crankshaft seal may be leaking just a little bit behind the flywheel because there is a little bit of oil on the belly pan. And my hydraulic cylinder has a faint amount on the piston rod. I have only run this tractor for 4hours since I purchased it but it's 31 years old. So ya'lls wisdom will be appreciated.