Rotax 912 i series Original operating manual

20 December 2017 Current valid documentation see: 12-10-00
www.FLYROTAX.com page 1 of 13
Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
d06525.fm
SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
This SI revises SI-912 i001R4/SI-912-016R9 and SI-914-019R9 dated 27 March 2017
SERVICE INSTRUCTION
Selection of suitable operating fluids for ROTAX®Engine
Type 912 i, 915 i, 912 and 914 (Series)
ATA System: 12-10-00 Operating fluids
1) Planning information
To obtain satisfactory results, procedures specified in this publication must be accomplished with
accepted methods and prevailing legal regulations.
BRP-Rotax GmbH & Co KG cannot accept any responsibility for the quality of work performed in
accomplishing the requirements of this publication.
1.1) Applicability
All engines of type:
1.2) Concurrent ASB/SB/SI and SL
None.
1.3) Reason
Introduction of the new engine type 915 i Series. Change of GAZPROM B-92 and B-92/115 from
Mogas to the aviation fuels.
1.4) Subject
Selection of suitable operating fluids for ROTAX®engine type 912 i, 915 i, 912 and 914 (Series).
1.5) Compliance
According Maintenance Manual of engine type ROTAX®912 i, 915 i, 912 and 914 (Series),
current issue.
1.6) Approval
The technical content of this document is approved under the authority of DOA ref.
EASA.21J.048.
1.7) Labor time
None.
1.8) Mass data
Change of weight - - - none.
Moment of inertia - - - unaffected.
1.9) Electrical load data
No change.
Engine type Serial number
912 i (Series) all
915 i (Series) all
912 (Series) all
914 (Series) all
mWARNUNG
mWARNING
Non-compliance with these instructions could result in engine damag-
es, personal injuries or death

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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
1.10) Software modifications
No change.
1.11) References
In addition to this technical information refer to current issue of
- Operators Manual (OM)
- Installation Manual (IM)
- Maintenance Manual (MM)
NOTE: The status of the Manuals can be determined by checking the table of
amendments. The 1st column of this table shows the revision status. Com-
pare this number to the are listed on the ROTAX WebSite:
www.FLYROTAX.com. Updates and current revisions can be downloaded
for free.
1.12) Other Publications affected
None.
1.13) Interchangeability of parts
- Not affected
2) Material Information
2.1) Material- cost and availability
None.

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SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
20 December 2017 12-10-00
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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
3) Lubricant
3.1) General
Foreign particles formed during combustion are suspended in the motor oil. Together with oil com-
ponents that are not sufficiently resistant to heat, these foreign particles can cause parts such as
pistons, piston rings, exhaust valves, etc., to seize and lead to problems.
On turbocharged engines, failing to ensure an adequate cool-down period prior to shut-off may
lead to particle deposits and cause damage to bearings and seals. Hard oil residues can obstruct
parts of the oil system and lead to damage.
- In addition to insufficient cool-down periods, the use of unsuitable oils and not obeying oil
change intervals can especially cause such damage.
- Long-term operation with an engine that is too cold and/or operating too long with an overly rich
fuel mixture can cause water and fuel contamination in the oil, reducing its lubrication capacity.
- Furthermore, long down times with oil that contains water and contaminants can cause corro-
sion damage, especially on the bearings, with serious consequential damage.
The criteria for correct motor oil selection are:
- Correct oil viscosity for cold starts and sufficient oil pressure at high temperatures.
- Good gear wear protection.
- Avoidance of clutch slipping due to use of additives.
- Insufficient oil flow capability causes too much volume to remain in the engine, leading to low
oil level in the external oil tank. This can only be detected during testing with an oil level indica-
tor installed on the oil tank.
- Ability to withstand combustion products containing lead, which enter the oil during AVGAS
operation.
- High oil temperature durability. This is especially important for the turbo engine due to the risk
of oil carbon buildup on the bearing and sealing seats of the turbocharger. The oil carbon build-
up (coking) can also flake off and block/restrict the oil return passage
Conclusions
- If possible, operate the listed engine types using unleaded or low-lead fuel. (AVGAS 100 LL is
not considered low leaded in this context.)
- Use the recommended motor oils tested and released by BRP-Rotax according to section 3.2
of this SI.
- Use only oil which is classified by ROTAX®standard (RON)!
- Due to high stresses in the reduction gears, oils with gear additives such as AeroShell Oil Sport
Plus 4 are highly recommended.
- Because of the incorporated friction clutch, oils with friction modifier additives are unsuitable
because this could result in clutch slipping during standard operation.
- Avoid oils strictly specified for use in Diesel engines. These may not be suitable due to insuffi-
cient high temperature properties and additives that may affect the operation of the slipper
clutch in the gear box.
- On turbocharged engines, always conduct a cool-down run before shutting down in accor-
dance with the relevant Operators Manual.
- Pay special attention to engine operation tips (see section 6).

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SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
3.2) Operation with unleaded and low-lead fuel (less than 0.1 g/liter lead content)
Motor oils tested and released from BRP-Rotax (for use with unleaded fuel or MOGAS),
which we recommend for use with our ROTAX® engine types 912 i, 915 i, 912 and 914
Series:
1) according to RON 424
2) with new formulation
3) in red bottle
* Specification RON 424: The ROTAX® Norm 424 (RON 424) is a BRP-Rotax internal standard,
which is only available on special request via the ROTAX® Authorized Distributor and will not be
disclosed to third parties without prior consent.
NOTE: The previous formulation of AeroShell Oil Sport Plus 4 can still be used until
its expiration date.
NOTE: The coefficient of viscosity indicates the tendency of oil to flow but it is not
necessarily a quality code. Country specific deviations of the viscosity are
possible.
mWARNUNG
NOTICE
When operating primarily on unleaded fuels or MOGAS, the maintenance
intervals remain unchanged in regard to the published maintenance
schedule found in the currently valid Maintenance Manual for the engine
type.
In case of severe operating conditions (operation in cold/hot weather ar-
eas, interference by and and/or salt), the time between maintenance inter-
vals must generally be shorter, and in particular, the frequency of oil
changes must be increased regardless of the type of fuel mainly used
(MOGAS or AVGAS).
Brand Description Specification Viscosity
SHELL®AeroShell Oil Sport Plus 4 1) 2) 3) RON 424* SAE 10 W-40

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SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
20 December 2017 12-10-00
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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
3.3) Operation with leaded AVGAS fuels
Perform maintenance checks according to the latest Maintenance Manual.
More frequent oil changes will assure timely removal of residues and oil sludge thus avoiding
increased wear or operating troubles.
Motor oils tested and released by BRP-Rotax (for use with leaded AVGAS), which we rec-
ommend for use with our ROTAX® engine types 912 i, 915 i, 912 and 914 Series:
1) according to RON 424
2) with new formulation
3) in red bottle
* Specification RON 424: The ROTAX® Norm 424 (RON 424) is a BRP-Rotax internal standard,
which is only available on special request via the ROTAX® Authorized Distributor and will not be
disclosed to third parties without prior consent.
NOTE: The previous formulation of AeroShell Oil Sport Plus 4 can still be used until
its expiration date.
NOTE: The coefficient of viscosity indicates the tendency of oil to flow but it is not
necessarily a quality code. Country specific deviations of the viscosity are
possible.
Brand Description Specification Viscosity
SHELL®AeroShell Oil Sport Plus 4 1) 2) 3) RON 424* SAE 10 W-40

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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
4) Coolant
4.1) General
All engine types 912 i, 915 i, 912 and 914 Series have liquid cooled cylinder heads and ram air
cooled cylinders. The function of the coolant is to protect the cylinder heads from over-tempera-
ture by means of heat dissipation. Protection against corrosion of the engine components and
freezing of the coolant is achieved with appropriate additives.
In principle, 2 different types of coolant are permitted:
- Conventional coolant based on ethylene glycol with 50% water content
- Waterless coolant based on propylene glycol (not allowed for 912 i and 915 i Series)
4.2) Conventional coolant
Conventional coolant (with about 50% water content) has a specific thermal capacity that is higher
than waterless coolant. It gives excellent corrosion protection, especially for aluminum, and pro-
tection against freezing.
NOTE: For exact monitoring of the coolant temperature, a limit has been set. This
is necessary because standard coolant based on ethylene glycol such as
BASF Glysantin in a 50/50 proportion mixture can boil at a temperature as
low as 120 °C (248 °F). Refer to the current Installation Manual for more
information and instructions.
NOTE: Coolant should be a low silicate and nitrite free formula. Follow coolant
manufacturer directions regarding mixture percentages etc..
Coolants with a mixture of 50% antifreeze and 50% of distilled water recommended by the
authorized distributors (not tested from BRP-Rotax).
NOTE: The following list is based on the experiences and local recommendation
by the authorized distributors. Coolant brands, with same designation, may
vary from one to the other region. Please contact the local distributor for a
recommendation.
mWARNUNG
NOTICE
Waterless coolant based on propylene glycol is not permitted for engine
types 912 i and 915 i Series.
mWARNUNG
NOTICE
The certification and determination of the correct coolant type must be
conducted by the aircraft manufacturer. As each aircraft type has different
characteristics, testing must be done to determine the most suitable cool-
ant and instrumentation for each aircraft type.
Brand Description
BASF®Glysantin Protect Plus/G48
CASTROL®Antifreeze All-Climate
CASTROL®Antifreeze Anti-Boil
OMV®OMV Coolant Plus
PETROL®Antifreeze Concentrate / Antifreeze G 11
PRESTONE®DEX-COOL extended life
PRESTONE®50/50 preluded DEX-COOL extended life
SHELL®DEX-COOL

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SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
20 December 2017 12-10-00
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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
4.3) Waterless coolant for engine types 912/914 Series
The coolant suppliers guidelines must be adhered to when filling or re-filling coolant.
NOTE: EVANS®Cooling Systems, Inc. offers its NPG+C coolant worldwide under
several names. For some recent examples, see also the next table. For any
naming, specification or successor products contact your local EVANS®
Cooling Systems, Inc. Official Partner
4.3.1) Warnings for operating with waterless coolant
- Water or coolant containing water must never be added to the cooling system!
- The max. water content must not exceed 3.6 %; it can be tested using a Brix refractometer.
- Any water present in the cooling system is separated out as vapor. This can cause the cooling
system to fail due to insufficient coolant quantity.
- If EVANS®coolant is not available locally for servicing the cooling system, a conventional cool-
ant based on pure 100% ethylene glycol can be used temporarily. However, the coolant must
be replaced again with EVANS®within the next 15 days.
SHELL®Antifreeze Concentrate
TEXACO®Havoline Extended Life Antifreeze
VELVANA®FRIDEX G49
YACCO®LR-35
Brand Description
mWARNUNG
NOTICE
Waterless coolant is not permitted for engine types 912 i, 915 i Series or
for 912/914 Series with cylinder head version Suffix - 01.
mWARNUNG
NOTICE
The certification and determination of the correct coolant type must be
conducted by the aircraft manufacturer. As each aircraft type has different
characteristics, testing must be done to determine the most suitable cool-
ant and instrumentation for each aircraft type.
mWARNUNG
NOTICE
EVANS®coolants are fully operational to -40 °C (-40 °F). It will not freeze
and expand like conventional coolant.
Brand Description
EVANS®
Aero Cool 180° Europe/Middle East
NPG+C China
Evans High Performance Coolant USA and rest of the world
mWARNUNG
NOTICE
As some conventional coolants are available in a pre-mixed formula (water
added) be sure to add only 100% pure ethylene glycol if EVANS®coolant
is not available.

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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
mWARNUNG
NOTICE
Regarding the temporary use of “100% pure ethylene glycol”. It should be
only a temporary measure. Using the concentrate over time would cause
the additives to drop out and possibly block cooling system passageways.
If true 100% pure ethylene glycol were used, it would be corrosive as it
would not contain any additives.
mWARNUNG
NOTICE
The above warnings are taken from the manufacturer’s users manual,
however the original text and description in the users manual is binding
(see: www.evanscoolant.com).

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SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
20 December 2017 12-10-00
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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
5) Fuel
For ROTAX® aircraft engines different fuel types are available. See Operators Manual of the rele-
vant engine type and/or the table in chapter 5.3.
NOTE: If none of the fuels mentioned in chapter 5.3 is available, consult the corre-
sponding European Standard EN228 as a reference. The fuel to be as-
sessed, has to be equal or better at least in terms of the octane number and
the maximum ethanol content.
NOTE: The aircraft manufacturer has to show compliance to the relevant require-
ments on aircraft level regarding vapor lock as this issue is strongly depen-
dent on the aircraft fuel system design.
5.1) Automotive fuels
In addition to AVGAS various automotive fuel types with different quality are available. Due to var-
ious environmental, economic and political reasons a number of fuel types with different amounts
of ethanol blend are available. Therefore the maximum amount of ethanol blend is defined as fol-
lows:
5.1.1) E10 (Unleaded gasoline blended with 10% ethanol)
In addition to AVGAS and unleaded automotive fuel (Mogas) the ROTAX® 912/914 Series of
engines are now approved for use with E10. Fuels that contain more than 10% ethanol blend have
not been tested by BRP-Rotax and are not permitted for use.
5.1.2) Suitability of fuel system components of airframe
BRP-Rotax urges owners to confirm with their airframe manufacturer that ethanol blended fuels of
up to 10% (E10) are compatible with all fuel system components.
It is the responsibility of the aircraft manufacturer to test their fuel system components and supply
any further information on techniques, procedures and limitations of using ethanol blended fuel.
BRP-Rotax recommends that aircraft manufacturer and owner/operators read the following:
- FAA Advisory Circular Letter AC 23.1521-2
- FAA Special Airworthiness Information Bulletin CE-07-06
- EASA Safety Information Bulletin – SIB 2009-02
These contain details regarding the use of ethanol (alcohol) blended fuels and the type certificate
requirements.
It is strongly recommended that non-certified aircrafts also conform to the information given in the
above documents.
5.2) AVGAS fuel additives
Additives under the names of Decalin® and Alcor TCP®, which aid the scavenging of lead depos-
its have not been tested by BRP-Rotax. Field experience shows that these products have no det-
rimental effect on the engine, when used in the recommended manner.
Always follow the additive manufacturers instructions especially with regard to health and safety
precautions. BRP-Rotax only has field experience with Decalin Runup® and Alcor TCP® brands.
Other similar additives are not recommended as BRP-Rotax cannot comment on their suitability
for the 912 i, 915 i, 912 and 914 Series engine types.

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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
5.3) Fuel according to local standards
The following fuels can be used.
NOTE: There is a risk of vapor lock formation if winter fuel is used for summer
operation.
Engine Type 912 A/F/UL - 912 S/ULS - 914 F/UL
mWARNUNG
NOTICE
Use only the correct fuel for the specific climate zones.
Usage/Description
912 A/F/UL
Min. RON 90
912 S/ULS - 914 F/UL
Min. RON 95
MOGAS
European
standard
EN 228 Normal
EN 228 Super EN 228 Super
EN 228 Super plus EN 228 Super plus
Canadian
standard CAN/CGSB-3.5 Qualität 1 CAN/CGSB-3.5 Qualität 3
Russian
standard
R 51105-97 R 51866-2002 R 51105-97 R 51866-2002
Regular-91/92 Regular-Euro-92
Premium-95 Premium Euro-95 Premium-95 Premium
Euro-95
Super-98 Super Euro-98 Super-98 Super Euro-98
South African
standard
SANS 1598:2006 SANS 1598:2006
Clean Fuels (CF2) Clean Fuels (CF2)
US standard ASTM D4814
(min. AKI 87)
ASTM D4814
(min. AKI 91)
Ukrainian
standard
DSTU 4839-2007 DSTU 4839-2007
A-92-Euro
A-95-Euro A-95-Euro
A-98-Euro A-98-Euro
Indian
standard
IS 2796:2008 IS 2796:2008
MG 91
MG 95 MG 95

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SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
20 December 2017 12-10-00
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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
1) unleaded, mainly available in the Scandinavian area
2) Fuels were verified as good at the time of our release.
We reject any liability if the fuel manufacturer changes the composition of the fuel.
Engine Type 912 iSc/iS and 915 iSc/iS
AVGAS
leaded AVGAS 100 LL ASTM D910 AVGAS 100 LL ASTM D910
unleaded UL91
ASTM D7547
UL91
ASTM D7547
released brand-name2)
GAZPROM B-92 GAZPROM B-92
GAZPROM B-92/115 GAZPROM B-92/115
unleaded HJELMCO 91/96 UL1) HJELMCO 91/96 UL1)
unleaded HJELMCO 91/98 UL1) HJELMCO 91/98 UL1)
unleaded TOTAL AVGAS UL 91 TOTAL AVGAS UL 91
Usage/Description
912 iSc/iS Sport
Min. RON 95
915 iSc/iS
Min. RON 95
MOGAS
European
standard
EN 228 Super EN 228 Super
EN 228 Super plus EN 228 Super plus
South African
standard
SANS 1598:2006 SANS 1598:2006
Clean Fuels (CF2) Clean Fuels (CF2)
DSTU 4839-2007 DSTU 4839-2007
Ukrainian
standard
A-95-Euro A-95-Euro
A-98-Euro A-98-Euro
IS 2796:2008 IS 2796:2008
Indian
standard MG 95 MG 95
Usage/Description
912 A/F/UL
Min. RON 90
912 S/ULS - 914 F/UL
Min. RON 95

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SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
2) Fuels were verified as good at the time of our release.
We reject any liability if the fuel manufacturer changes the composition of the fuel.
NOTE: The Anti Knock Index (AKI) is valid for fuels according to ASTM D4814, and
for fuels which are defined by AKI instead of RON.
NOTE: AVGAS 100LL places greater stress on the valve seats due to its high lead
content and forms increased deposits in the combustion chamber and lead
sediments in the oil system.
Usage/Description
912 iSc/iS Sport
Min. RON 95
915 iSc/iS
Min. RON 95
AVGAS
leaded AVGAS 100 LL ASTM D910 AVGAS 100 LL ASTM D910
released brand-name2)
unleaded TOTAL AVGAS UL 91 TOTAL AVGAS UL 91
GAZPROM B-92 GAZPROM B-92
GAZPROM B-92/115 GAZPROM B-92/115

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SI-912 i-001R5 / SI-915 i-001
SI-912-016R10 / SI-914-019R10
SERVICE INSTRUCTION
20 December 2017 12-10-00
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Copyright - BRP-Rotax GmbH & CO KG. All rights reserved.
6) General engine operation requirements and operating tips
1. Keep the motor oil temperature below 120 °C (250 °F) over most of the operating period.
2. Always insure that the oil type used is adequate for climatic conditions and peak engine operat-
ing temperatures. If operational oil temperatures exceed 120 °C (250 °F), use of a mineral or
petroleum based oil is not recommended.
3. For turbocharged engines ensure an adequate running cool-down period to prevent deposits
by coking of oil.
4. When operating with unleaded fuels or MOGAS and when engine oil temperatures often
exceed 120 °C (250 °F) use of a high quality full synthetic oil is recommended.
5. To avoid formation of condensation water in the motor oil, the oil temperature must rise at least
once every operational day to at least 100 °C (212 °F).
6. Avoid extended use of carburetor air pre-heating when safe and reasonable.
7. Depending on the type of fuel used, operating conditions, and the demands of the engine mis-
sion profile it may be necessary to increase the frequency of oil changes to avoid the excessive
build up of lead and other residues in the engine oil. Always adjust the engine oil change inter-
vals to avoid excessive build up of sludge in the engine oil.
Excessive engine vibration, particularly at low idle speeds, can impair the carburetor fuel metering
system leading to a too rich mixture condition. This rich mixture condition can further lead to rough
engine operation and excessive carbon and lead deposits.
7.1) Summary
These instructions (section 3) have to be followed in accordance with the deadlines specified in
section 1.5.
A revision bar outside of the page margin indicates a change to text or
graphic.
Translation into other languages might be performed in the course of language localization but
does not lie within ROTAX®scope of responsibility.
In any case the original text in English language and the metric units are authoritative.
7.2) Inquiries
Inquiries regarding this Service Instruction should be sent to the ROTAX®Authorized Distributor
of your area.
A list of all ROTAX®Authorized Distributors or their independent Service Centers is provided on is
provided on www.FLYROTAX.com.
mWARNUNG
NOTICE
Do not use oil additives and observe the operating limits as per the rele-
vant Operators Manual.