Small Engines (Lawn Mowers, etc.): Briggs & Stratton Sucking/Blowing Oil, briggs stratton, crank case

Question
QUESTION: I have a 7 horse Briggs (Engine #17042 0143-01 6906141)that appears to be blowing oil out of the crank case ventilation chamber on the front of the engine. From there the oil flows down the return tube and in to the air intake pipe then gets sucked in to the engine and burnt. it will actually suck its self dry and stall out. I have taken apart the crank case and checked the piston and rings (they appear good to me) the valves seem to seat fine as well, the valve springs also look good. I'm at a loss on this one..? any help would be appreciated!

Thanks

Mike

ANSWER: Hello Mike:

If you Removed the Piston from the Cylinder and Did Not Deglaze the Cylinder, then the Rings Can Not Re-Seat to the Cylinder and Blow By Compression is the Cause for this Problem. If the Breather was Doing this Before you Disassembled the Engine, then the Breather May have Needed Cleaning. If this is an OHV Engine and the Head Gasket is Blown Between the Valve Push Tubes and the Cylinder, this Problem will Occur. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John

---------- FOLLOW-UP ----------

QUESTION: This engine is not a OHV. After some research I found it was actually built in June of 1969. The breather was blowing oil and that is the reason I took the engine apart. While Reassembling the engine I cleaned out the breather yet the problem still exists. Although I did not deglaze the cylinder before reinstallation. I'm not even sure how to do that. any further thoughts would be of much assistance and greatly appreciated.
Thanks

Regards

Mike

Answer
Hello Again Mike:

You will Need to Deglaze the Cylinder and Make Sure the Ring Gaps are Set at 12 O'clock, 4 O'clock and 8 O'clock Position on the Piston. Did you Check the End Gap of the Rings? The Ring End Gap Should Not be More Than .030in. The Proper Ring End Gap and Deglazing the Cylinder are the Most Common Causes for the Problem if the Crankcase Breather is Clean and Operating Properly. A Deglazing Tool can be Purchased from your Local Automotive Parts Retailer. Be Sure and Tell them it is for a Small Engine. A Wheel Cylinder Hone Does Good on these Small Engine Blocks. Use Plenty of Oil and Remove the Slick Surface from the Cylinder. The Cylinder Hone Attaches to your Drill. Then Remove the Top Ring from the Piston and Insert it Into the Cylinder and Check the Ring End Gap at 1/2" , the Middle and the Bottom of the Cylinder. No More than .030in End Gap is Permitted. .030in is Considered a Worn Out Ring Set. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John