Avoid Over-Filling Oil in Ford, Lincoln and Mercury Engines - Engine Builder Magazine

Avoid Over-Filling Oil in Ford, Lincoln and Mercury Engines

Figure 1Incorrect
oil levels are being found in many 2002-2003 Ford, Lincoln and Mercury
vehicles. In most cases, the level is being misinterpreted because the
oil level on the dipstick is not touching the top hash mark at the
upper limit (or MAX mark), or it is partway down the crosshatch area.

is in the process of standardizing the marking across all vehicle
lines. The markings shown in Figure 1 were scheduled to be upgraded to
a refined marking, but both markings were still being used in many 2004
and 2005 models. Oil levels will continue to be recorded in the
crosshatched area of the blade, between the upper and lower limit
holes. Vehicles with engine oil levels falling within this area are
acceptable and do not require topping off.

Service Procedure For Your Installers Customers

the vehicle is sitting on level ground. Set the parking brake and make
sure the transmission selector lever is in the Park position or in
First gear on manual transmissions. The engine must be off.

best time for determining oil level is after the oil has had sufficient
drain-back time to the sump. If the engine has been running, allow it
to sit for a few minutes turned off. An oil drain-back period is
required before taking an initial reading.

the level falls below the lower hole, fill with one quart of oil. If
one quart is insufficient to raise the level above the lower mark, add
oil until it records within the crosshatch area. Use caution during
this procedure as some time is needed for oil to drain down through the
drain-back passages in the cylinder head to the oil pan. Adding oil a
quart at a time repeatedly without sufficient drain-back may overfill
the sump.

If the oil level falls between the upper and lower
holes, do not add more oil. Adding an extra quart could cause
over-filling and may result in aeration (foaming) causing eventual
damage to vital bearing surfaces and moving parts inside. Over-filling
will require some oil to be drained until the indicator shows the level
between the upper and lower holes of the blade. An extra quart of oil
should never be considered as additional lubrication protection for the

For additional information on ALLDATA, visit www.alldata.com.

Diegle is technical editor at ALLDATA. Diegle is an Advanced Engine
Performance Certified ASE Master Technician with an AA degree in
automotive technology and 23 years of dealership and independent shop


Additional Tech Tips>>

You May Also Like

LTR Engine Build

This Late Model Engines build is centered around Concept Performance’s new LTR block, which is the first aftermarket as-cast aluminum Gen V LT block. 

The Chevrolet LT engine family from General Motors is rooted in the early ‘70s, when the LT1 was featured in the Corvette and Camaro Z28. After a 20-year hiatus, GM reintroduced the platform in the early ‘90s. The “LT1 350” came out in 1991, and was distinct from the high-output Gen I LT1 of the 1970s. It displaced 5.7L (350 cu in), and was a two-valve per cylinder pushrod design. The LT1 used a reverse-flow cooling system, which cooled the cylinder heads first, maintaining lower combustion chamber temperatures and allowing the engine to run at a higher compression than its immediate predecessors.

LS Intake Manifolds

LS swaps are popular for many reasons, but there are a lot of variations and details to sort through – more of them than you may expect – and many of them are associated with the intake manifold.

LS Cylinder Heads

The LS engine is known for its cylinder heads, and there are tons of options available to upgrade the factory components.

Choosing the Correct Block for Your LS Engine Build

Whether you’re scouring junkyards, ordering cores, investigating factory options, looking at aftermarket cast iron or aluminum blocks, or spending big bucks on billet LS blocks, you’ve probably noticed it’s been harder to find exactly what you want for the foundation of your LS build than it historically has.

Open Loop/Closed Loop and Learning

Closed-loop control can be programmed to either add or subtract up to a certain percentage of fuel in order for the engine to reach the target air/fuel ratio.

Other Posts

Shop Solutions January 2023

Next time you have set of large journal small block Chevy connecting rods to resize, consider honing the big ends of them for a +.002” outside diameter bearing that the LS engines with fracture cap rods use.

Shop Solutions December 2022

Everyone misses occasionally, and this helps avoid dents and damage.

Jesel Certified Performance Rebuilds

Engine components are serious investments for any racer and maintaining that investment could be the difference between winning a championship and losing it.

Going the Extra Mile with Cylinder Head Porting

It’s not just the port work alone that creates spectacular cylinder head performance. The most critical areas of a cylinder head are those which pass the most air at the highest speed and for the longest duration. Your bowl area, the valve job, the throat diameter, and combustion chamber are all crucial parts.