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1998 Harley Davidson FXDL low rider " Dynasor"
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You've asked this every time it's come up and been told why every time it comes up, please stop asking, you're not gonna get a different answer.

External breathing is not necessary and won't make much difference on a stock or near stock engine, and it won't solve any breather issues. The engine doesn't "breath more" with a breather being external. The only thing an external breather does is keep hot, oily air out of the intake, which can mean a cleaner running engine, and not dirty up an air filter with oil, and allow for cooler air intake, which is better for worked engines since they already run hotter.

A stock engine that pukes oil through the breathers has a problem somehow like bad piston rings that lets too much air in the case, a clogged breather system, bad umbrella valves, etc.

Some worked engines will puke oil at highway speed simply because the breather systems weren't designed for the power of the engine. An engine that pukes oil in such a case will always puke oil regardless of external breather or not, it won't fix an oil puking scenario, but at least it will keep loads of oil out of the intake if it does puke. You might think they're a pain, but they're not, and putting one on doesn't cause oil to puke, not ever. Again, external breathers will not cause an engine to puke oil from the breather system.
I am so glad you monitor my questions 馃槅 I asked respectfully and yes in the past ? was asked. I see repetitive questions constantly here about the most basic stupid crap imaginable. Your answer was the best explanation I heard. When you. Or someone quotes my answer to you I am sure it will be edited out of context. As it has many times. A salute to your rude post.馃枙
 

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Discussion Starter · #22 ·
Thank you Schmidty for explaining how the oil pump & pressure relief valve can cause the oil to be pushed out through the air cleaner, I didn't know that. It seems that could be the problem with my bike and will be the next thing I will check!
 

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The reason I questioned the OP is that servicing the tensioners is a procedure that also involves servicing the cam support plate and the oil pump. The cam support plate has a relief valve that can hang up, the oil pump has gear rotor plates that can wear, pump o-rings that leak over time and miles, all can affect oil pressure. A worn oil pump can cause the crankcase to partially sump which causes excess case pressure in turn pushing excess oil thru the breathers. Remember what happens with EVOs that sump, oil pumps out of the case breather hose all over the floor !
Or right in front of the rear tire as you are pulling away on a right turn. Happened to me. That event had a high "pucker factor".
 

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Mr. James
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o_O
 

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ya overfilled the oil tank.
The OP stated that the oil level is halfway between add and full...

OP, it is not normal for a healthy engine to slobber a lot of oil out the breather, I suggest a compression test or leakdown test to determine if there is a mechanical issue causing the excessive blow by.
 

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I answered you apparantly it got deleted too bad you didn't read it. As it disappeared in seconds, must be that freedom of speech that is only allowed blah blah blah....
So I`m confused, is the oil blowing out the breather on the OP`s bike the fault of the Democrats, or the Republicans?:ROFLMAO:

Take the stupid political BS elsewhere, this is a technical forum.
 

old scoot coot
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The OP stated that the oil level is halfway between add and full...

OP, it is not normal for a healthy engine to slobber a lot of oil out the breather, I suggest a compression test or leakdown test to determine if there is a mechanical issue causing the excessive blow by.
oops, dan i didn't see part about the level. my bad.
 

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Been along time ago but if I remember right the two hydraulic tensioners do not wear the same. The one you need a mirror for wears out quicker. I replaced mine at 40,000 with some from Zippers. Much better than the stock tensioners. The breather for the crankcase run through the air filter is a common problem. Triumph did the same. What a joke. Reroute and be done with it.
 

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Discussion Starter · #31 ·
Did a compression test today, 150psi both front & rear. When I was running the bike I noticed oil being pushed out of the rocker cover gaskets. I was super careful to install the gaskets correctly and cleaned the surfaces very well. I assume that the oil is being pushed out because of too much pressure in the rocker box.
 

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You've asked this every time it's come up and been told why every time it comes up, please stop *** asking, you're not gonna get a different answer.

External breathing is not necessary and won't make much difference on a stock or near stock engine, and it won't solve any breather issues. The engine doesn't "breath more" with a breather being external. The only thing an external breather does is keep hot, oily air out of the intake, which can mean a cleaner running engine, and not dirty up an air filter with oil, and allow for cooler air intake, which is better for worked engines since they already run hotter.

A stock engine that pukes oil through the breathers has a problem somehow like bad piston rings that lets too much air in the case, a clogged breather system, bad umbrella valves, etc.

Some worked engines will puke oil at highway speed simply because the breather systems weren't designed for the power of the engine. An engine that pukes oil in such a case will always puke oil regardless of external breather or not, it won't fix an oil puking scenario, but at least it will keep loads of oil out of the intake if it does puke. You might think they're a pain, but they're not, and putting one on doesn't cause oil to puke, not ever. Again, external breathers will not cause an engine to puke oil from the breather system.
Ive heard of a easy fix by using a vented oil dipstick
 

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I am not sure if you solved your oil problem, if not my 01 fuel injected road king had the same problem and it was the alignment of the oil pump. The dealer admitted that there is some movement when mounting the oil pump and if it is off a little you can build up pressure that can cause the problem you are having. Dealers have a alignment tool that they use when installing replacement pumps.
 

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Discussion Starter · #34 ·
I took the cam plate off and can't see anything obvious causing the problem. I check the pressure relief valve, it came out easily, no residue or pieces from the tensioners, although the rear shoe was worn out. The oil pump had some tiny grooves which appears to be just normal wear to me, but I'm going to replace it anyway, along with the inner cam bearings and tensioners. Someone else had mentioned the alignment of the oil pump, so I will install the new one strictly by the book. Hopefully this will solve the problem.
 

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FYI there's a very specific procedure to follow when installing the TC oil pump and cam support plate. The pinion shaft runout should always be checked after the cam plate and pump are removed. Pinion runout cannot be corrected without complete engine disassembly by machine shops using specialized equipment.
Without getting into a prolonged lengthy discussion on TC crankshafts and considering that the pinion runout is within spec (.003 - .004") then the oil pump is installed behind the cam plate with loose screws then the crankshaft is rotated several revolutions to center the pump behind the cam plate then the pump screws are torqued to spec.
Also lifter block alignment tools can be used to center the oil pump but in the end rotating the engine several revolutions centers the pump as well as can be.
 
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