Hello peeps.Question for ya.I've got a MTD rider with a 12.5 Briggs & Stratton that is pumping oil into my carb.Replaced the head gasket but the oil is still pumping out of a small hole located inside the breather box.The hole is about the diameter of a toothpick on the bottom right.I turn the engine by hand and it pumps out a pretty good stream.Not to mention there is also gas in this oil.Something a basic guy could fix or should I junk it out.Any help would be greatly appreciated.Thanks,take care and be safe out there.
Oil pumping out of hole in breather box
- Thread starter rebelwind
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Check the oil level on the dipstick
Sounds like the main problem is the carburetor Needle and seat failed filling the crankcase oil up with gasoline. drain the gas and oil out of the crankcase, it's best to change the oil at least twice and the filter to be sure all the gas is out of there.
Give us the model number, (should be stamped on the valve cover if it's an Over head valve OHV, engine) or above the spark plug if it's a flat head.
Sounds like the main problem is the carburetor Needle and seat failed filling the crankcase oil up with gasoline. drain the gas and oil out of the crankcase, it's best to change the oil at least twice and the filter to be sure all the gas is out of there.
Give us the model number, (should be stamped on the valve cover if it's an Over head valve OHV, engine) or above the spark plug if it's a flat head.
Thanks Scrubcadet.I will give that a try.Read it on a couple of other sites but haven't goen around to it.Model is #28T707.Can ya tell me the purpose of that hole I mentioned?I've been through all of my manuals but it's never been mentioned.Again,thanks bud.
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Could you post a picture of the hole in question?
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just upload to a image hosting site, i use postimages.com, and copy the link it provides here.
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I'm not sure, but it may be a return drain back to the crankcase for the oil. Or it may just be a air vent for the crankcase since the cover Acts as the breather.
One of the Techs on here will probably know
One of the Techs on here will probably know
Hammermechanicman
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That is the oil drainback hole. How it works. When the engine runs the entire crankcase is filled with a mist, not vapor, of oil. The cover you removed has a piece of sponge and a oneway valve in it. When the engine pushes oil mist filled air into the breather the oil is precipitated out and collects in the breather. There are 2 small holes at the bottom or side of the breather that the oil drains out of the breather and back into the engine and then through the small hole you indicate. The one way valve and sponge filled cavity is how the engine vents crankcase pressure but doesn't lose oil with it. Don't install the breather or breather gasket upside down or backwards.
If you are pumping oil up into that hole the oil level in the engine is way too high.
If you are pumping oil up into that hole the oil level in the engine is way too high.
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Changed theoil of course that was mostly gas.Installed fuel control valve and cleaned carb.Added fuel and oil and she seems to be running pretty good.I appreciate your help bud.Enjoy your weekend and be safe.