Table of Contents

EVO: Engine Mechanicals - Sub-01C

1986-2003 Sportster Engine Case Identification


The engine cases below are grouped by the year span they were installed on.
Notice the casting numbers follow the same pattern although there may differences in color and minor machining within a group.

Interchangeability

Welded kickstand mount locations: 2)

1986-1990 Sportster Cases

1986 Sportster and some E1987 Left and Right Outer Cases 3)
1987-1989 Sportster Left and Right Outer Cases 4)
1990 Sportster Left and Right Outer Cases 5)
1990 Sportster Left and Right Inner Cases 6)

1991 Sportster Cases

1991 Sportster Left and Right Outer Cases 7)

1992-1994 Sportster Cases

The oil pressure relief system was deleted as was the discharge hole at the filter pad into the cam chest.
A .060“ hole was drilled from the oil feed galley in the upper right case into the cam chest as a #2 cam squirter.
This hole also doubles as a high pressure oil relief with the excess oil being used to spray onto #2 can gear.

1992-1994 Sportster Left and Right Outer Cases 8)
Left and Right Inner Case Views 9)

1995-1997 Sportster Cases

1997 XLH883 Left and Right Outer Cases 10)
1996 XLH883 Left and Right Inner Cases 11)

1998-1999 Sportster Cases

1998-1999 Left and Right Inner Cases 12)

2000-2002 Sportster Cases

2000-2002 XL1200C Left Outer Case 13) 2000-2002 XL1200C Right Outer Case 14)
2000-2002 Left and Right Inner Cases 15)

2003 Sportster Cases

2003 was the 100th anniversary for HD.
The upper front of the left case was cast for a 100th anniversary medallion sticker just under the front cylinder.

Specific Engine Case Features

Motor Vin Pad / Location

Starting in 1970, the bike is titled to the frame only and the same number set is stamped on the motor.
Starting in 1981, the motor VIN is only an abbreviation of the frame VIN.
So the numbers on the motor will not fully match the 17 digit VIN on the frame or the title.
But if it is the motor that came with the frame, it will be the same set of numbers as on the frame but with some left out.

Various Numbers Found on Cases

Case Part Numbers

Click Here to see an article on Part Numbers in general in the Sportsterpedia.

You will not find any part numbers on the cases that match the parts listings in the parts catalogs.
Part numbers were never cast or stamped into the cases. Each case half has many numbers on it but none of them show up in the parts books.
There were some parts that did have part numbers on them either stamped or on a sticker label.
Some electrical parts had stickers with the part number on them but no part numbers on cases.

The parts catalog listings are for logistics in which the MoCo stocks parts, sells them to dealerships and customers all under one Part Number.
Basically the part number was created to move the product, not to build the product.
Moving the product can mean, to the builders at the factory, mechanics at the dealership or to the customer.
Part numbers are used in manuals and instructions .
Part numbers are assigned after the parts are built (more accurate to be said the part will be listed as XXXX part number when it gets built).

Each case half has a casting number, not to be confused with a part number. See below.
Beginning with 1976 models and up, cases were only sold as a set so there are no individual part numbers for left or right case halves.
There is only 1 part number that includes both case halves.

Casting Part Numbers

Click Here to see an article on Casting Numbers in general in the Sportsterpedia.

Casting numbers on the left and right cases look like (are coded like) part numbers but they are not.
They were put there when the case half was created (cast) and represent a certain base design.
Unlike part numbers, casting numbers do pertain to the building of the part. One could also call them design numbers.
A casting part number does not pertain to any certain model.
Many different year / model motors may carry the same casting numbers but there will still be differences that are important to know.
When the main design changed, so did the casting numbers, but not until then. However, the part number may change several times.
Some cases with the same casting number will have different machining done for the year model they pertain to.
Some will have different size holes / ports etc. (example of machining done after the part was cast).
Some will be different due to a running change in the way the casting was done.

Casting part numbers per years used:

Casting Date Code

Early 1987 Case (L) and Late 1987 Case (R) 16)
1988-1990 Left and Right Inner Case Date Codes 17)

Crankcase Numbers

These numbers were originally stamped on the bottom of each case half in the early days and was known as Belly Numbers.
Crankcase numbers don't have anything to do with issuing a VIN.
1957-1985 crankcase#s will not tell you specific model info (XLH or XLCH) and is coded only for the XL family of engines.
1986-present crankcase#s will have a number code representing the size of the engine (883, 1100 or 1200cc).
1991-present motors changed the coding and numbering system several times. See below for those changes.
Engine serial / VIN numbers are added later after assembly.

Crankcase numbers tell you that a particular set of cases was paired up and finish machined together (line boring, cylinder base surfacing etc).
These numbers will tell the year model that the cases are intended to be used, the Julian date and sequential number that day.
The coding for the crankcase numbers changed in 1986.
HD Model Designation (changed to 2 digits) - Year Model Case (2 digits) - Julian Day of the Year (3 digits) - Sequential Number (3 digits)
Each case half should have the same exact crankcase numbers as they came assembled from the factory as such.

From 1986 to mid 1989, crankcase numbers were hand stamped with “Pann-Ident style” numbers.
Starting mid 1989, crankcase #s are “pin stamped” by machine with “block style” and look as though they were formed by a series of “center-punched” dots.
The punch marks are deep enough that they should be able to be recovered with acid after grinding.
The back-up system for the new automated process is the old style hand stamping.
Therefore, it is possible that in the event of a mechanical failure of the pin stamping machine;
Some crankcases, after mid-model year 1989, may have hand stamped numbers.
If that happened, Harley-Davidson will have records of what crankcase numbers were hand stamped.

Below are numbers found on different year Sportster cases and should only be used as a guide.
There may be other numbers that don't match the ones below but these have all been verified.

1986-1990 Sportster Crankcase Number Locations 18)
1991-1999 Sportster Crankcase Number Locations 19)
2000-2003 Sportster Crankcase Number Locations 20)

Case Match Numbers (1975-Up)

In addition to belly numbers, there is a second set of numbers on 75> motors on each case half that should match.
This was added the same time the left case crankcase number moved from the belly to the primary wall on 1975 models.
For lack of public documentation, we'll call these Case Match Numbers and they represent the fact that those two case halves were mated as a factory pair.
These will most likely be a letter(s) and numbers but the exact number set should be on the outside of each case half opposite one another.
The factory crankcase numbers should be the same and the case match numbers should also be the same.
There does not seem to be any connection between the case match numbers and belly numbers (no date coding visible on case match numbers).

1986-1990 Case Match Number Locations 21)

Serial or VIN Numbers

These numbers pertain to the whole bike, not just the engine. Coding for these numbers changed over the years.
Click Here to see the VIN page in the Sportsterpedia for specific information on serial/Vin numbers.
One Sportster may have many different parts, over the whole bike, than others, including engine parts.
The serial/VIN number was (most likely) the last number to be stamped onto the engine case from the factory.
1970-up Sportsters are titled to the frame only so the motor VIN number has nothing to do with ownership of the bike.
However, having the motor abbreviated VIN matching the frame VIN is a plus for those who want factory original parts.
And it helps toward the value (or haggle factor) on resell but the VIN is not the only factor in whether you have an original engine or bike.

Case Drains

The only intended drain on 1986-2003 models is the primary drain plug.
All models either drain engine oil from the oil tank or a hose from the tank.

1986-2003 cases have a vertical boss on the right case at the rear sump wall as an oil return passage from the crankcase to the oil pump passage.
Some year cases have a plug (like a small freeze plug) pressed into the bottom case plugging off oil passages.
Some cases have a set screw instead of the plug. But neither are supposed to used for draining engine oil.
There is no crankcase drain on any of these models.
However, the plug at the bottom of the rear vertical boss on the right case has been used to drain (most) of the oil in the crankcase.
It won't drain it all though. The front vertical boss on 1991-1997 cases was used to lower the point where cam chest oil drained into the crankcase.
Removing that plug will not drain anything from the crankcase but it will drain whatever oil stacked up in it and the cam chest.
(shouldn't be that much oil in the cam chest anyway)
1998-2003 cases do not drain cam chest oil into the crankcase at all so the front vertical boss on the right case is not drilled / plugged.

Drains / plugs on the bottom of the cases:

1986-1990 case drains 22) 1991-1997 Sportster case drains 23) 1998-2003 case drains 24)

Left Case

Left Crankcase Oil Scavenge

On all models, oil scavenging to the pump and engine breathing is done by way of machining in the right case.

1986-1990 Left Case Drainage 25) 1991-1997 Left Case Drainage 26) 1998-2003 Left Case Drainage 27)

Right Case

Upper Oil Feed Galley

The upper feed galley is a distribution point for oil feed from the pump.

1986-2003 Upper Oil Feed Galley Changes 28)

Oil Pump Mounting Boss and Oil Passages

Click Here to reference the Evo Sportster Oil Pump page in the Sportsterpedia.
Note: Mixing full oil pump assemblies and engine cases is much easier than mixing individual oil pump parts.

1986-present cases use a gerotor type oil pump but there is a major difference in plumbing between 86-90 models and 91-up models.
However, 1986-1990 cases can be modded to accept 1991-up oil pumps.
Click Here to reference the 5 Speed Oil Pump Conversion for 86-90 Evo engines.

1986-1990 Oil Pump Mounting Boss 29) 1991-2003 Oil Pump Mounting Boss 30)

Right Case Oil Scavenge / Engine Breathing

1977-up motors scavenge oil from the crankcase thru an external vertical boss added to the outside of the rear sump area.
The boss is rifle drilled from the bottom to connect to the upper horizontal oil passage to the oil pump.
A hole is drilled from the inside of the right case to connect sump oil to the return passage.
The bottom of the rifled hole in the vertical boss is plugged.

1986-1990 Sportster right case
general oiling and breathing paths 31) 		1991 (only) Sportster right case
general oiling and breathing paths 32)
1992-1997 Sportster right case
general oiling and breathing paths 33) 		2000-2003 Sportster right case
general oiling and breathing paths 34)
1986-1990 Inner Right Case 35) 1991-1997 Inner Right Case 36)
1998-1999 Inner Right Case 37) 2000-2003 Inner Right Case 38)

High Oil Pressure Bypass

1986-2003 high pressure bypass configurations 39)

Primary / Transmission External Vent (1986-Present)

Click Here to reference the Trans/Primary Oiling page in the Sportsterpedia.

1986-1990 Transmission Vent 40) 1991-1999 Transmission Vent 41) 2000-2003 Primary Vent 42)


1)
fcarlos085 of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/frame-mount-evo-sportster-talk-1986-2003-models/75511-4-to-5-speed-engine-swap-questions/page2?t=533976&page=2
2)
composite of pics used with permission
3)
photos courtesy of Robert Evans
4) , 16)
photos courtesy of c3cycle.com, Link to site: https://www.c3cycle.com/
5)
photos courtesy of Ebay seller, chezyrydr. Link to Items for Sale page
6) , 33) , 35) , 36)
photo courtesy of West Chester Cycles Inc. Link to Ebay Store
7) , 10) , 21) , 22) , 23) , 24) , 30) , 32) , 34) , 40) , 41) , 42)
photo courtesy of c3cycle.com, Link to site: https://www.c3cycle.com/
8) , 9) , 19)
photos courtesy of West Chester Cycles Inc. Link to Ebay Store
11) , 15) , 20)
photos courtesy of Ebay seller, gnarlydavidson1. Link to Items for Sale page
12) , 26) , 27) , 37)
photo courtesy of Ebay seller, Cycle Parts 4U, Link to Ebay Store
13) , 14) , 38)
photo courtesy of Ebay seller, gnarlydavidson1. Link to Items for Sale page
17)
photos courtesy of Ebay seller, The Part Resource Link to Ebay Store
18)
photos courtesy of Robert Evans, labeled by Hippysmack
25)
photo courtesy of Ebay seller, The Part Resource Link to Ebay Store
28)
composite from chezyrydr, c3-cycle-tech, West Chester Cycles Inc and gnarlydavidson1
29)
photo courtesy of Robert Evans
31)
photo courtesy of Robert Evans, labeled by Hippysmack
39)
composite using pics from Robert Evans - c3-cycle-tech - gnarlydavidson1