How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Steve Your Own Question
Steve, Motorcycle Mechanic
Category: Motorcycle
Satisfied Customers: 6907
Experience:  30+ yrs. experience, MMI, HD technician, HD early, engine rebuild/performance, bike builder, kit bike program manager, CCI 2001-2004
Type Your Motorcycle Question Here...
Steve is online now
A new question is answered every 9 seconds

Oil from crankcase vent on 1982 1340 cc shovelhead engine, what

This answer was rated:

i am dripping oil from crankcase vent on 1982 1340 cc shovelhead engine, what should i check?

Welcome. Thank you for choosing Just Answer.


since the bike has been setting for that time, the oil dump is common and expected.

the problem is called "sumping".

oil gravity feeds past the check ball in the oil pump and overfills the gearcase.

when you start the engine, the breather system does what it is suppose to.....vent excess crankcase pressure and get rid of excess oil accumulation.

the official HD factory answer is.....add a length of oil line to the breather hose and stick it into the dipstick spout BEFORE starting the engine. it will then just add the oil back to your oil tank.

this is also why it is important to change or top off the oil tank if the engine and oil are at operating temperature.

let me know if your problem continues after riding the bike.

there could be other problems which we an discuss at that time.


Customer: replied 5 years ago.
Added extra line to cranlcase vent- oil fill. Started motor ( oil coming ouy ) and let idle for 3-4 minutes. removed line and rode bike for approx. 5 minutes. Some oil is still dripping from vent. Noticed oil level in tank slightly high, oil pressure is around 15 - 19psi.normal?

lower the oil level to the correct level.

an overfilled oil tank will result in oil dripping from the breather.


you will have some drips from the breather hose for a was full of oil. it will take some time for all of the oil in the hose to drip out. not to worry.


15-19 psi when? at what temperature? at what speed?



Customer: replied 5 years ago.
Steve, Will lower oil level to correct level. Oil pressures where at idle and warm engine- not sure of exact temps.How long of ride to clear sump of excess oil? and what if it keeps happening?

15 - 19 psi at idle is good.

Harley has no spec on idle oil pressure. basically, if the light is out, you are good to go.

it is important to note that, Harleys do need the same kind of oil pressure as your car.

the main engine components are on roller bearings and the bushings are "drip feed".

you can tell if your oiling system is operating correctly by looking into the tank with the engine running.

if you see signs the oil is moving, you are good.

if you see stagnant've got problems.


it's not possible for me to ell you after you ride (X) number of miles the drips will stop.

it should stop or be barely noticeable after around 30-50 miles of continuous riding.

a little drip here and there is not uncommon.

you shouldn't worry about unless you can't maintain oil tank inventory or the bike leaves a puddle every time you park it.


you should also be aware the "sumping" issue will never go away.

it will happen ever time you park the bike for more than a few weeks at a time.

there is a home remedy you can try, but it seldom works and requires removing the oil pump from the engine.

let me know if you want instructions.

the two best solutions are A) don't let the bike set for more than a week without riding continuously until oil temp reaches about 200F, and B) replace the oil pump. (S&S would be my suggestion)

let me know if you need more help.


Customer: replied 5 years ago.
What would be a cause if the bike leaves a puddle everytime i park it.

worn oil pump.


excessive crankcase pressure from worn rings.


overfilled oil tank.


restricted breather valve.


Customer: replied 5 years ago.
Do you think i should check/replace the ball check, spring on oil pump? ( May have some dirt on it and not seating correctly? ) I still have to check if I can see the oil moving inside the oil tank. Can I contact you tomorrow with this info? Thanks Steve

replacing the ball and spring will usually have no affect.

the problem is the seat.

this required pump replacement.


let's do this......ride the bike.

let me know what kinds of problems, if any, you still have you put about 50 miles on it.

now you have an excuse to go for a ride! LOL


let me know what the status is tomorrow.

just respond to this reply when you have more information.

I'll be here.


Steve and 2 other Motorcycle Specialists are ready to help you
Customer: replied 5 years ago.


Thanks for the help and info. oil is still dripping but very slowly now.