new shaft seal? Running rough and smoking

[jlatenight]

Hi, My craftsman mower with a 20hp Intek single barrel is acting up and I need some advice. oil is dripping from underneath the engine, there oil seeping around the base of the engine where it bolts to the chassis. It runs ok if it's idling for the most part, but when I turn the blades on it makes this weird cyclical sound which I attached. It smokes a lot too. I changes the oil/filter, looked at the carb and it looked fine inside. Oil's at the right level. I think it's getting enough fuel. The inline filter has a puddle in the bottom of it, but it's not half-filled by a long shot. Is that ok? I guess I need a main drive shaft seal? Would that account for it running rough and the leaking around the base of the engine? I attached a video but had to zip it. Thanks!

 

[Rivets]

You need to find the source of the leak first. First thing I would do is to pressure wash the entire unit and make everything is clean and very dry. Second I would run the unit looking for oil leaking out. From your pics it could be anywhere, from top ( lhead or valve cover gaskets) to bottom (crankcase gasket, oil seal, etc.). From the pics I’m guessing (which I hate to do) it is not an oil seal, but something higher up.

 

[StarTech]

And use UV dye to find the leak. It takes the guess work out.

 

[jlatenight]

If I pressure wash it (which I've wanted to do anyway) it's going to make a huge mess. I'm thinking it might be better to remove the engine, clean it, and prop it up to see where it's leaking. Were you able to unzip the video? Sounds really weird

 

[andrewslarge]

Wise to remove the engine to find the source of the oil leak

 

[Auto Doc's]

I would suspect the oil filter is not sealing properly. If it also has an oil cooler mounted near the oil filter, they have an O-ring seal to the block that will leak.

Clean it up (top and bottom sides) and use an oil dye to find the truth. Pulling the engine without proof is a lesson in futility. Oil under the mower is just a product of gravitation and oil creep.

The running problem sounds like it is fuel related, possibly a restricted fuel supply at the fuel tank.

 

[slomo]

Look at all that dirty oily rust preventative under there. Looks like a leaker for quite a while.

Check the engine block vent and reseal her up.

Keep a sharp eye on the oil level.

 

[Tiger Small Engine]

I would suspect the oil filter is not sealing properly. If it also has an oil cooler mounted near the oil filter, they have an O-ring seal to the block that will leak.

Clean it up (top and bottom sides) and use an oil dye to find the truth. Pulling the engine without proof is a lesson in futility. Oil under the mower is just a product of gravitation and oil creep.

The running problem sounds like it is fuel related, possibly a restricted fuel supply at the fuel tank.

Removing the engine versus pressure washing the engine to locate the oil leak. Talk about trying to make the job more difficult and time consuming.

 

[Legal v8]

+1 to pressure washing. Far less work than removing the heavy engine and not having the ability to run it to find the source of the leak unless you have an open bench to boot it on with a battery and fuel system setup. Not really ideal circumstances IMO.