Oil Fill Plug Blowing Off

Question for Fix My Hog My Harley is cranking but not getting fire, when I crank on it for a min or 2 the oil cap blows off…before I go and spend money that might not fix the problem I would like to get some advise on what I can do.

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Fix My Hog Answers Would tell you to check for spark 1st, but the oil fill plug blowing out is a concern. Is it possible that your oil tank is over full, or your fill plug is a loose fit? Check for spark and confirm that you are getting fuel.

Related Fix My Hog Videos:

https://www.fixmyhog.com/video/harley-davidson-ignition-coil-test-008707/

https://www.fixmyhog.com/videos/carburetor-rebuild/

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11 Responses to “Oil Fill Plug Blowing Off”

  1. Pappy frith

    How many QTS of oil goes in a 2013 soaftail heritage.

  2. Rolland

    I have a similar problem. I AM HAVING DIFFICULTY WITH MY 1992 EVO POWERED HERITAGE SOFTTAIL. OIL IS DUMPING OUT THE CRANKCASE BREATHER WHEN THE ENGINE IS CRANKED OVER, EVEN IF THE ENGINE DOES NOT START. IT APPEARS TO ME THAT EXCESS PRESSURE IN OIL SYSTEM MAY BE THE CULPRIT. IMMEDIATELY AFTER TURNING OVER THE ENGINE, WHEN I LOOSEN OR REMOVE THE OIL FILLER CAP, A RUSH OF AIR CAN BE HEARD BEING SUCKED INTO OIL TANK AS IF THE OIL TANK WAS IN A STATE OF VACUUM OR NEGATIVE PRESSURE? REMOVAL OF THE OIL FILLER CAP APPEARS TO EQUALIZE THE OIL PRESSURE THERE BY STOPPING THE FLOW OF OIL OUT OF THE CRANKCASE BREATHER. iF THE OIL CAP IS NOT REMOVED OR AT LEAST OPENED, THE FLOW OF OIL GRADUALLY SLOWS AND THEN STOPS AFTER PUKING OUT A LOT OF THE OIL, (MAYBE A QUART +/-). THIS SAME SCENARIO HAS OCCURRED SEVERAL TIMES IN THE PAST AFTER THE BIKE WAS STORED FOR ANY LONG PERIOD OF SEVERAL MONTHS OR MORE. CAN ANYONE HELP ME UNDERSTAND WHAT IS GOING ON? HOW DO I RECTIFY THIS SITUATION?.

  3. Tom Hile

    Check your oil level when the bike is on the side stand, on a level surface and cold. The oil level should just touch the bottom of the dipstick. I have found on my 2012 Softail Heritage, that when it gets hot (in town riding) if the oil level is up even a 1/4 or 3/8 in. up the dipstick(this is the one with the temp gauge needle in it) oil will spite out the seal.

  4. Mo Mowry

    I had an old ironhead that would blow the cab off.when it was cold. Ended up being the crankcase pressure relief.

  5. Cb

    Probably over filled with oil. On a softail or sporster never put more oil in than you get out. Softail twin cams often wet sump and hold oil in the motor that you can't drain - thus over filling is common. But also make sure oil blow by behind air cleaner is un obstructed. If that isn't it, then you may have a restricted internal oil line or obstruction to the oil blow by outlets.

  6. PHIL

    looking to hook up trailer wiring for my 2005 Electra Guide Standard, where would you recommend that I splice into the harness?

  7. Larry

    Mine used to do the same if ur not overfilled then the rubber plug part of the dip stick is old and dried up just buy a new dip stick...mine was for a 1999 fat boy

  8. Hobo

    The bolt nut that hold my seat on the back fender fell true what's a quick fix without taking the fender off

  9. Danny

    Maybe a breather line plugged or restricted

  10. Robert Traylor

    Would you be able to tell me where the vent is for the clutch on my 2014 Harley Davidson Fat Boy Lo? The clutch cable was replaced by a Harley Service Department about 6 months ago because it was leaking. I noticed this morning that oil was dripping out of the clutch cable on the bottom of the adjuster. I have heard that the vent maybe clogged.