Emil Akhundov
Member
Hello everyone. Does anybody met with big oil leakage from engine case breather(located near to oil pump) during engine running on TP 107'' ? Will appreciate any explanation of that problem.
Crank case breather big oil leaking issue
- Thread starter Emil Akhundov
- Start date
BigDogRick
Well-Known Member
Emil,
You probably are seeing the natural blow by of the breather line that ends in your air intake for the carburetor. Oil migrates slowly up the breather tube and makes its way out through your air filter. With time, it accumulates and releases a drip at a time from the bottom of your breather cover (tear drop). It is irritating but natural. Many relocate the breather tubes so that the oil drops to the ground. I have never done that but once and did not keep it that way. I just tolerate the accumulation of small drop-off oil on the sid of my bike and wipe them off. It is minimized if you do not over fill your oil reservoir. This is really important. If you do over fill, it will breath the excess oil all over the side of your bike. The purist may find this a ridiculous continuing condition. I have found it tolerable for 15 years an almost 80,000 miles. Its your call.
You probably are seeing the natural blow by of the breather line that ends in your air intake for the carburetor. Oil migrates slowly up the breather tube and makes its way out through your air filter. With time, it accumulates and releases a drip at a time from the bottom of your breather cover (tear drop). It is irritating but natural. Many relocate the breather tubes so that the oil drops to the ground. I have never done that but once and did not keep it that way. I just tolerate the accumulation of small drop-off oil on the sid of my bike and wipe them off. It is minimized if you do not over fill your oil reservoir. This is really important. If you do over fill, it will breath the excess oil all over the side of your bike. The purist may find this a ridiculous continuing condition. I have found it tolerable for 15 years an almost 80,000 miles. Its your call.
Emil Akhundov
Member
Frank,
yes, post a pic please. Thanks for help guys!
Emil Akhundov
Member
Rick,
The problem is when I'm starting bike, oil is sprays out like some pump is pumping it out from breather hose. It is not just small leaking. That scares me. On my 2010 Wide Glide I installed oil catch canister and rerouted breather hoses from air filter to canister to keep it clean from oil. Works ok.
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Emil Akhundov
Member
Fond some info also:
Trouble shooting oil coming out top end & CRANK CASE PRESSURE
To much oil in engine case, causing crank case pressure. Like a balloon building pressure until it escape’s. Oil will blow out at the weakest point.
Recently change oil, possibly over filled oil tank.
Take in consideration when changing oil. You will have approx ¼ cup
Of oil left in bottom of engine case. Know what size oil tank you have before you start filling your tank with oil. Stock soft tail is 3-1/4 qt oil. Oil filters are like sponges they will absorb approx ¼ cup of oil. Don’t over fill because the oil level looks low.
Oil filter blocked or if Blowing oil filters off
Hand turning oil filter, must turn 1/4 by hand, then use oil filter wrench made by Harley turn an additional 3/4 turn.
When hand tightening oil filter, not using a wrench, if not tight enough oil filter WILL BLOW OFF from pressure.
Oil filter mount or oil cooler lines crossed or hooked up backwards.
Wrong oil filter will cause major blow by. No after markets used here.
THIS IS FOR TP ENGINES
Classic oil filter part # 63796-77A EVO oil filter 40 micron
Smart oil filter can use either 5 micron, 10 micron or 40 micron
Part # 63798-99A (5) micron filters dust
Part # 63798-99 (10) micron filters small particles
Part# 63796-77A (40) micron
Restricting breather bolts, bolts too small. Vent holes for breathers should be (.187). Make sure when putting extension on breather bolt holes are not Covered, Defeats the purpose.
Oil returning in tank, vent and return are not covered in oil. This will suck oil back into engine not allowing it to breathe properly and will cause blow by, engine will get very hot.
Vent and Return lines inside tank, broken.
Poor return
Pinched hose
Collapsed line
Race track gaskets, torn, bubbled, or worn should be replaced.
Piston sealing problem, low miles engine not seated yet
Oil cooler too high and or lines routed incorrectly.
Rocker box lids are backwards. Front lid on Rear and the Rear on the Front.
Keep in mind if having blow by issue's even after changing all your gaskets or o-ring’s, unless rocker boxes cavity's, carb, etc are cleaned out with break cleaner you will have left over residue that will still blow out, eventually all blow by will be gone.
Trouble shooting oil coming out top end & CRANK CASE PRESSURE
To much oil in engine case, causing crank case pressure. Like a balloon building pressure until it escape’s. Oil will blow out at the weakest point.
Recently change oil, possibly over filled oil tank.
Take in consideration when changing oil. You will have approx ¼ cup
Of oil left in bottom of engine case. Know what size oil tank you have before you start filling your tank with oil. Stock soft tail is 3-1/4 qt oil. Oil filters are like sponges they will absorb approx ¼ cup of oil. Don’t over fill because the oil level looks low.
Oil filter blocked or if Blowing oil filters off
Hand turning oil filter, must turn 1/4 by hand, then use oil filter wrench made by Harley turn an additional 3/4 turn.
When hand tightening oil filter, not using a wrench, if not tight enough oil filter WILL BLOW OFF from pressure.
Oil filter mount or oil cooler lines crossed or hooked up backwards.
Wrong oil filter will cause major blow by. No after markets used here.
THIS IS FOR TP ENGINES
Classic oil filter part # 63796-77A EVO oil filter 40 micron
Smart oil filter can use either 5 micron, 10 micron or 40 micron
Part # 63798-99A (5) micron filters dust
Part # 63798-99 (10) micron filters small particles
Part# 63796-77A (40) micron
Restricting breather bolts, bolts too small. Vent holes for breathers should be (.187). Make sure when putting extension on breather bolt holes are not Covered, Defeats the purpose.
Oil returning in tank, vent and return are not covered in oil. This will suck oil back into engine not allowing it to breathe properly and will cause blow by, engine will get very hot.
Vent and Return lines inside tank, broken.
Poor return
Pinched hose
Collapsed line
Race track gaskets, torn, bubbled, or worn should be replaced.
Piston sealing problem, low miles engine not seated yet
Oil cooler too high and or lines routed incorrectly.
Rocker box lids are backwards. Front lid on Rear and the Rear on the Front.
Keep in mind if having blow by issue's even after changing all your gaskets or o-ring’s, unless rocker boxes cavity's, carb, etc are cleaned out with break cleaner you will have left over residue that will still blow out, eventually all blow by will be gone.
cdogg556
Guru
I don't know if this is the same problem my buddy has on his "Fat Boy" harley, It's one of the first Fat Boy's made, he says after it's been sitting for a while that when he fires it up a lot of oil come out of the crank case breather tube! It was a pretty good size puddle of oil, I'd say 7 or 8 inches around! He tells me that it's normal if the bike has been sitting for a while! Sounds similar to what you are experiencing with your bike. I gotta say it don't sound normal to me though!
Emil Akhundov
Member
This case is very similar to my story, because my bike was collecting dust in previous owner's garage more than one year and never started
.
Emil Akhundov
Member
I hope it will stop for a while on my bike too. Cross fingers.
heybaylor
Active Member
sounds like the check valve in your oil pump is leaking.
It is called "wet sumping" I/e the bikes sits for awhile ,and the oilbag drains into the crankcase.
when you start it, the way too much oil in the crankcase is forced out of the :breather ..( it is a "dry sump motor)
easy fix ..several ways to do it . do a seach on "wet sumping"
hope this helps
It is called "wet sumping" I/e the bikes sits for awhile ,and the oilbag drains into the crankcase.
when you start it, the way too much oil in the crankcase is forced out of the :breather ..( it is a "dry sump motor)
easy fix ..several ways to do it . do a seach on "wet sumping"
hope this helps
Emil Akhundov
Member
Thanks dude. Will check it out.
heybaylor
Active Member
yes , you should keep it clean because it keeps grit out of the tappets.
but wont cause the oil to blow out the breather
Emil Akhundov
Member
I cleaned it when I was changing gaskets...
Emil Akhundov
Member
After discussion with TP Engineering mechanic , he explained me that it is happening very often when bike staying for a long time. Oil from all the engine is collecting in the crank case during bike is stays long period and when you starting the bike extra oil is starts leaking from the crank case breather. What you need to do, just collect that oil coming from breather into some storage pan and ride the bike untill leaking will stop itself. Two breathers crank case and heads breathers must be opened always. It's not needs non retern check valve for TP engine rear cylinder like S&S engines has. Thanks to everyone for support! 
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cdogg556
Guru
That's what my buddy was saying too! Glad you figured it out!After discussion with TP Engineering mechanic , he explained me that it is happening very often when bike staying for a long time. Oil from all the engine is collecting in the crank case during bike is stays long period and when you starting the bike extra oil is starts leaking from the crank case breather. What you need to do, just collect that oil coming from breather into some storage pan and ride the bike untill leaking will stop itself. Two breathers crank case and heads breathers must be opened always. It's not needs non retern check valve for TP engine rear cylinder like S&S engines has. Thanks to everyone for support!
Now all you gotta do is just ride it so the leaking stops!
Emil Akhundov
Member
John,That's what my buddy was saying too! Glad you figured it out!
Thanks for that. Feel myself mutch better now.
Sounds right to me! Isn't that what I said in your other post ? HahaAfter discussion with TP Engineering mechanic , he explained me that it is happening very often when bike staying for a long time. Oil from all the engine is collecting in the crank case during bike is stays long period and when you starting the bike extra oil is starts leaking from the crank case breather. What you need to do, just collect that oil coming from breather into some storage pan and ride the bike untill leaking will stop itself. Two breathers crank case and heads breathers must be opened always. It's not needs non retern check valve for TP engine rear cylinder like S&S engines has. Thanks to everyone for support!
Only thing I don't know why TP would say you NEED both breathers open. Like I said before it's highly preferred but not NEEDED. Head breathers are NEEDED but I guess I'm just playing with words. If they are there run them both!
Also the comment about the check valve is only applicable to the SSW+ engines. None of the 107 Big Dogs have them, they are the older SSW and no +. S&S came out with that new design with the 117 and it's on 05+ dogs.
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