FH580V Upper Engine Oil Leak(s)

LSU-Mike

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This topic came up after I started a thread about my starter on this engine. Seemed like a new thread is in order:
One or more significant oil leaks have existed for sometime causing quite a mess on the entire upper engine (mostly hidden by the engine cover). Txmowman pointed to the breather plate gasket and/or upper shaft seal as possible villains. After removing the flywheel I believe I might as well replace both. Other than performing an extreme cleanup before starting this effort, are there any caveats I should be aware of? I don't have the knowledge or tools to open the engine, so please don't suggest that. Even with the serious oil-based debris on the engine, it ran very strong and smooth before the starter issue...especially considering it's 17 years old. It's on a Scag Freedom Z.

I don't know if it's allowable to mention vendor names, but here goes: I found an online parts source at jamessmallengines.com. There are very detailed diagrams there, and the prices don't seem too outlandish. Can anyone comment on their reliability and delivery timeliness? Other suggestions?
Thanks
 

Bertrrr

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The Crankcase will be split at the bottom part of your engine, if it's oily residue towards the top , I suspect it's from a breather plate or tube that's venting from the crankcase or valve stem area. Unless you're having to add a bunch of oil to the machine , I would just keep an eye on it for now until it gets worse
 

StarTech

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Or flywheel side crankshaft seal.

BTW I used Jack's for years; they are a little different now with the new owners. I however outgrew them with me landing two oem distributors.
 

hlw49

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If the top main seal is leaking you should check the top main bearing and crank shaft for wear. To do this turn the fly wheel toward the magnets and push and pull really hard to see if there is play in the bearing and crank shaft. If this is the problem It won't do any good to replace the seal as it will just wipe it out again. Your engine is toast unless you know a really good machinest to turn the crank and make a bushing for the block. It won't effect the sealing area of the crank as it is above the bearing area of the crank.
 

LSU-Mike

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Thanks for the replies folks. I'll proceed with the expectation to begin looking for a new mower.
 
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