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Hi, first time here. Hoping I can pick your brains and ya'll can point me in the right direction.

9 rear old B&S twin 446777 0302 Cub Cadet LT1024 (MTD Clone) w/ 465 hours use.
Dumping lots of oil, looked like it was #2 cylinder head gasket... oil pooling under head. Replaced head gasket... didn't fix it.

Just now realized the oil is exiting out the top of the engine, under the fly wheel and running down the block to the #2 head. I haven't taken off the fly wheel yet. Also, I'm working without a manual but I do have the parts break down. Is the upper (magneto side) oil seal accessible without removing the crank???? Can I get to it by removing the flywheel? Or...

Thanks in advance, neil

Yes, you can get at it by removing the flywheel. Yes, you can get at it without removing the crank. Can you do it successfully? I don't know how good you are as a mechanic. If you try to replace it here are some pointers. 1. Be careful not to scratch the crank on removal, or you may be replacing the crank. 2. If you get it out successfully, you will need something like a large pipe or seal driver, the same size as the new seal, to drive it in squarely. 3. Install the new one with a good assembly lube, not just motor oil. Post back if you decide to attempt this and I will get the torque specs for you.

Thank you Rivets, I will be attempting it. I am mechanically inclined. White Lithium a good assy lube?

Be careful, flywheel torque is 150 foot pounds. White lithium will work as an assembly lube for the new seal. I would use it liberally. Take it slow on removal.

The fly wheel is off. Wasn't sure which would snap loose first, the fly wheel or the puller. I've got to dig around for something to seat the new seal tomorrow.

Anything that might cause the seal to leak (blow)? Is there a pattern failure maybe??? Like a blown head gasket creating pressure in the crank case? Does the crank case vent? There is what looks like a vent tube from the crank case to the carb throat. Maybe that's it? It's not clogged. Maybe I'm over thinking this?

Here's a pic:

You've found your problem. After you install the new seal and get ready to run it I'll give you a simple test to check for excessive crankcase pressure.

Thanks Rivets, tomorrow after work.

The new seal is in but it's not all put back together yet.

Here's a tip when you get it ready to run and want to check to if you have too much pressure in the crankcase. Start the engine and run at medium speed. Remove the oil fill cap and set it back down on the tube. If it bounces wildly you have excess pressure, probably blown head gasket. You should feel some pressure coming out, which is normal.

Rivets said:

Here's a tip when you get it ready to run and want to check to if you have too much pressure in the crankcase. Start the engine and run at medium speed. Remove the oil fill cap and set it back down on the tube. If it bounces wildly you have excess pressure, probably blown head gasket. You should feel some pressure coming out, which is normal.

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Good info, thanks. I'll do that.

There is a breather assy. You can see it in the pic just south west of the oil seal with the tube coming out of the top. I've got a new gasket for it and now is the only time I'll have access to it with the fly wheel off. It there any reason I should take it off and replace the gasket?

Go for it. With the flywheel off, I would also clean the cooling fins. I just looked at the pic again, I would also clean up the starter drive and relube it.

Got it, good deal. I'll get it done tonight... lawn's getting tall.

Alright. Back together enough to run it. Hmmmm
Oil cap isn't dancing wildly but it is definitely dancing. Maybe bouncing 1/4 . I braced the motor to dampen vibration. Still dances.

I have a head gasket and can make a valve cover gasket. I did replace #2 head gasket already thinking it was the cause of the leak.

That does not sound bad. If you want to you could replace the head gasket, but I would give it a try and see what happens. What does your gut say?

Rivets said:

That does not sound bad. If you want to you could replace the head gasket, but I would give it a try and see what happens. What does your gut say?

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Ok, my gut said try it. Ran about 10 minutes with no problem.... then started blowing oil out the upper main seal again.

I'll probably have a new head gasket on the #1 side by the time you read this.

This is fun right?

Sorry to say, but not for me. I didn't think you would have to. Is is driving out the entire seal or leaking between the seal and shaft?

My best guess is that it's leaking between the shaft and the seal. I couldn't see anything wrong with the old seal. I was expecting to see a rip in it. The old seal was seated properly before I yanked it out.

Since the flywheel is in the way, I can't actually see the oil flowing out. I can only see it running down the block after it warms up. Again, it only happens after warm up.

:thumbdown: Replaced head gasket #2. Same thing. Runs for 10 to 15 minutes then starts spewing oil out of the top seal.

Thinking back...
I changed the oil a week before this started... could a faulty oil filter cause this??

Did you check that breather when you changed the gasket?

Might be a dumb question but... what's to check?

Replaced oil filter and breather.... runs 10 minutes, blows oil.

Snipehunter said:

Replaced oil filter and breather.... runs 10 minutes, blows oil.

Click to expand...

The seal. Seated flush against the casing or should it be lower.. pressed down into the casing. The old one was flush so that's how I did the new one. . Should it have been flush or set-in?

This web site explains it better than I can. How Small Engine Breathers Work | eHow.com

So will this one. http://www.g-w.com/PDF/SampChap/60525_5475_CH13.pdf

Found a crack in the casing near the upper seal yesterday. I guess I could have rebuilt it but with close to 700 hours... I bought a new mower.

Thank you for all the help

That's a new one for me. Learn something new every day. Good luck with your new mower.