August 10, 2005
Diagnosing Oil Consumption **BE AWARE, NOTICE WHERE THERE GOING WITH THESE SUGGESTIONS!!

There has been a rise in oil consumption complaints on 2005 – 06 model year vehicles.
The intent of this Tech Tip is to help you determine if there is an actual oil consumption
issue and more accurately diagnose the root cause.
1. First, determine if there is excessive oil consumption by analyzing the customer
complaint and vehicle condition.
• Many times fuel delivery related issues cause smoking complaints and may even
gas wash cylinders leading customers to believe they have an "oil burner" on their
hands.
• Is the vehicle modified and what is its state of tune?
• Does the EFI calibration match the actual components on the vehicle?
• Is there fuel stand off in the air cleaner or manifold?
2. What is excessive consumption?
• Customers may not realize that all engines have some normal rate of oil
consumption, and air cooled engines are more prone to use some oil in the course
of normal operation. It would not be unusual for a Twin Cam engine to use one
quart of oil in 1500 miles or a middleweight powertrain to use one quart of oil in
1000 miles.
• Oil consumption is impacted by engine condition, mileage, duty cycle (how the
vehicle is operated and in what environmental conditions), and accessories.
• Is the vehicle through its break-in period? Remember rings must seat before they
will begin to seal the cylinder to piston clearance.
• After a discussion with the customer on the complaint and a brief inspection of the
vehicle you should be able to determine if you a dealing with a rich condition, oil
consumption complaint, or customer misperceptions.
3. Determine the real rate of consumption.
• To determine the rate of oil consumption bring the oil level to the full line following
the "Checking With Warm Engine" procedures outlined in the service manual and
tape the filler neck closed.
• Have the customer ride the vehicle and inspect the level at 500-mile intervals to
determine the actual rate of consumption. Be careful not to overfill the tank, as that
will provide a false indication of consumption.
• If the rate of consumption exceeds the norm, you will need to review duty cycle with
the customer and then begin your inspection of the engine's state-of-tune
accordingly.
August 10, 2005
4. Verify the system before you tear it down.
• Don't overlook the obvious items before disassembly. How are the oil hoses (tight
clamps, routings, etc.)?
• Verify breather operation, this might be a carry-over situation. If you blow lightly into
the breather snorkels, there should be some resistance if the umbrella valves are
closing properly.
• Verify oil pressure and oil return functions. You might be dealing with an oiling
system issue and/or a wet-sumped lower end.
• Take a compression reading and perform a leakdown test. Remember to write down
the numbers, Technical Service is sure to ask for them.
• If leak down exceeds 10% determine where it is leaking by. Into the lower end, out
the exhaust or intake port, or through a head gasket?
5. Now begin your disassembly based on your findings, and keep both eyes open
as you take things apart for clues to the root cause.
• If the leakage was primarily into the crankcase, then you are chasing a piston to
cylinder sealing issues. To rule out a barreled or tapered cylinder re-check leak
down in three places (top - middle - bottom) in the stroke once the rocker arm
support plate is removed.
􀂃 By the way how did those umbrellas look, and was the rocker box fairly well
scavenged? No clogged return passages right? No signs of leakage at the head
gasket oil returns? Good gasket surfaces?
􀂃 Check the piston crown for carbon build up. Washed areas on the edges of the
piston crown are a good indication of an "oil pumper" (bad rings or piston

 

I have a 2005 Screaming Eagle Electra Glide Classic (w/ Stock SE 103ci engine w/ Stage One air cleaner kit & Hooker mufflers on it). It has about 29,000 miles on it.

I had problems with oil dripping out of the air cleaner and spraying oil on my right saddlebag when on long rides. I took it to my HD dealer this spring & they replaced the umbrella valves on the engine breather system. It seemed to correct the problem for several thousand miles but now it just started to do it all over again.

My friend said that the problem is most likely due to having the oil level at the top of the full mark on the dipstick when hot which causes Harley's twin cam engine to load up with oil on the top end & suggested that I keep the oil level closer to the halfway full mark on the dipstick when reading it hot.

I don't abuse the engine, but I do some high speed cruising on long distance rides.

Does that seem like the cause of the problem?

 

[QUOTE=ptomory;3836445]I have a 2005 Screaming Eagle Electra Glide Classic (w/ Stock SE 103ci engine w/ Stage One air cleaner kit & Hooker mufflers on it). It has about 29,000 miles on it.

I had problems with oil dripping out of the air cleaner and spraying oil on my right saddlebag when on long rides. I took it to my HD dealer this spring & they replaced the umbrella valves on the engine breather system. It seemed to correct the problem for several thousand miles but now it just started to do it all over again.

My friend said that the problem is most likely due to having the oil level at the top of the full mark on the dipstick when hot which causes Harley's twin cam engine to load up with oil on the top end & suggested that I keep the oil level closer to the halfway full mark on the dipstick when reading it hot.

I don't abuse the engine, but I do some high speed cruising on long distance rides.

Does that seem like the cause of the problem?

 

The manual says the oil should be at the top when the engine is hot.The oil level should be in the middle when the engine is cold. [hd service manua].