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Sequence VG Procedure

 

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  image of stand that runs the Sequence VG test, which evaluates a lubricant's ability to prevent sludge and varnish formation
 

The Sequence VG procedure evaluates a lubricant's ability to prevent sludge and varnish formation.

The Sequence VG test evaluates a lubricant's ability to prevent sludge and varnish formation. It is a replacement test for Sequence VE, ASTM D 5302, sludge and varnish. Moderate temperature taxicab service, urban and suburban delivery service, or job commuting service is simulated.

 

The Sequence VG lubricant test is an engine dynamometer test that duplicates the Sequence VE application, except that wear is not evaluated.

 

Specifications are:

  • API SL

  • API SM

  • ILSAC GF-3

  • ILSAC GF-4

Sequence VG Test Equipment and Procedure

A 2000 Ford 8-cylinder, 4.6-liter fuel-injected gasoline engine, with roller followers, coolant-jacketed rocker covers, and camshaft baffles is used. This 216-hour test involves 54 cycles, each cycle consisting of three differing operating specifications or stages.


Unleaded Haltermann SVGM2 fuel is used, and engine blowby is intentionally increased. Rocker cover jacket temperature is cycled.


Sequence VG Test parameters are as follows:

 

PARAMETERS

STAGE 1

STAGE 2

STAGE 3

Time, minutes

  120

    75

  45

Engine Speed, rpm

1,200

2,900

700

Load, Manifold Abs. Press., kPa

    69

    66

Record

Oil Temp., °C

    68

  100

  45

Coolant Temp., °C

    57

   85

  45

Rocker Cover Temp., °C   

    29

   85

  29


Sequence VG Test Results

At test end, experienced technicians evaluate:

  • Sludge deposits

    • Rocker arm covers

    • Cam baffles

    • Timing chain cover

    • Oil pan and oil pan baffle

    • Valve decks

  • Varnish deposits

    • Piston skirts

    • Cam baffles

  • Clogging

    • Oil pump screen

    • Piston oil rings

Inspections are conducted for:

  • “Hot” stuck piston compression rings

  • “Cold” stuck piston compression rings

Measurements are conducted for wear on:

  • Roller follower pins

  • Piston ring gaps

Used lubricant analysis includes:

  • Kinematic viscosity

  • Tin content

  • Iron content

  • Silicon content

  • Copper content

  • Pentane insolubles

  • Aluminum content

  • Fuel dilution

  • Lead content

  • Total base number

Sequence VG Pass/Fail Criteria

PARAMETER

PASS LIMIT

Average engine sludge, minimum

     7.8

Rocker cover sludge, minimum

     8.0

Average engine varnish, minimum 

     8.9

Piston skirt varnish, minimum 

     7.5

Oil screen clogging, % maximum

20

Hot stuck compression rings 

None

Oil screen debris 

Rate & report

Oil ring clogging 

Rate & report

Cold stuck rings 

Rate & report

Follower pin wear, avg. 

Rate & report

Ring gap increase, avg.

Rate & report

 

For more information about the Sequence VG procedure, or how you can contract with Southwest Research Institute (SwRI), please contact Dan Worcester at dworcester@swri.org or (210) 522-2405.

 

sequencevg.swri.org

 

Contact Information

Dan Worcester

Sequence VG Procedure

(210) 522-2405

dworcester@swri.org

sequencevg.swri.org  

Related Terminology

Sequence VG test

API SL

API SM

ILSAC GF-3

ILSAC GF-4

lubricant

sludge

varnish

engine blowby

oil pump screen 

clogging

piston oil rings

Related Information

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| Engine Lubricants Research Department | Fuels and Lubricants Research Division | SwRI Home |

Southwest Research Institute® (SwRI®), headquartered in San Antonio, Texas, is a multidisciplinary, independent, nonprofit, applied engineering and physical sciences research and development organization with 11 technical divisions.

December 28, 2012