Velvet Drive specs: weights, capacities, ratios

These numbers come straight off the factory paperwork for each family: service manuals, owner's manuals, spec sheets and parts catalogs. They're grouped by series below, because a single "Velvet Drive spec" doesn't exist across the whole product line.

71C/72C (1017/1018)

Ratios run 1:1 direct drive plus reductions at 1.523:1, 1.88/1.91:1, 2.10:1, 2.57:1 and 2.91:1. On a 72C, reverse always turns about 10% deeper than forward at every ratio, right down to the 1:1 (which is 1.10:1 in reverse). On a 71C, forward and reverse are equal. It's a clean way to tell the two apart if the tag is gone. The 1.88:1 and 1.91:1 reductions also turn the output opposite the input; every other 71C/72C ratio turns the output the same way as the input.

Capacity isn't fixed either. It changes with installed angle: a 71C 1:1 holds about 1.3 qt at a 15-degree installed angle versus 1.8 qt level, and a 72C 1:1 goes from about 1.7 to 2.1 qt the same way. Reductions run about 2.5-2.9 qt depending on angle. Factory max installed angle is 15 degrees at rest and 20 degrees bow-high underway; go steeper than that with low oil and the pump can suck air in rough water.

73C

The 73C is the heavy-duty sibling most people never see: prefix 10-06, ratios 1.00, 1.50, 2.00 (counter-rotating) and 3.00, dry weight 135 lb direct / 185 lb reduction. Its case is bigger than a 72C's: 5.94 in versus 5.63 in on one case dimension, and a 5.75 in coupling versus 5.00 in. See the 73C series page for identification and parts.

1004/1005 V-drive

One catch on the 10-04 prefix: older tags numbered 10-04-000-022 through -035 are 70C in-line units, not V-drives, so read the whole number before you call it a 1004 V-drive.

Ratio pairs run from 0.96:1 to 3.14:1 across six nominal ratios, gear-drive and chain-drive versions of each: 1.99/1.98, 2.50/2.49, 3.10/3.14, 0.97/0.96, 1.53/1.51 and 1.21/1.21 (gear/chain). A gear-drive V-drive turns its output the same direction as the engine; a chain-drive V-drive turns it opposite, which is how the two V-drive models let twins run same-rotation engines.

5000 and Liberty

Nominal and actual ratios aren't quite the same number, and both show up in factory paperwork:

Weights disagree across the factory's own documents, which is worth knowing before you argue with a spec sheet: the Liberty owner's manual and brochure list 114 lb for the 5000A and 135 lb for the 5000V, both service manuals list 100 lb for the 2001/3001, and the V-drive supplement lists 133 lb for the 2002. Use whichever document matches the paperwork you're holding, or just call us.

Capacity: 5000A about 2.01 qt, 5000V 3 qt, Liberty 3001 2.0 qt, Liberty 3002 3.0 qt. A 5000 or Liberty only bolts up behind an engine that turns counterclockwise at the flywheel (Velvet Drive calls this a left-hand engine; ZF's paperwork calls the same engine right-hand turning); which way the prop turns is set by which lever direction you rig as forward, not by the engine.

CR-2 (1013/1014)

CR-2 is a counter-rotating drop-center gearset built so two same-rotation engines can drive a twin-screw boat with opposite-turning props: prefix 10-13 on 71-series internals, 10-14 on 72-series. The distributor spec sheet lists ratios of 1.58, 2.03, 2.47 and 2.93, though we usually just call them by round numbers, 2.1:1 and 3:1.

Duty classes

Factory ratings are given per duty class, not one flat number:

• Pleasure: full throttle about 5% of the time, cruise at 80% of rated rpm or less, 400 hours a year or less. A pleasure hull used for charter or party fishing still counts as light-duty commercial, not pleasure.
• Light-duty commercial (LDC): full throttle about 5% of the time, longer running at 75% of rated rpm or less, 1,500 hours a year or less.
• Heavy-duty commercial (HDC): full throttle about 5% of the time, longer running at up to 80% of rated rpm, 2,500 hours a year or less.

The 71C's own charts show no heavy-duty commercial rating at all; it tops out at LDC. For comparison, a ZF63 (which we also service) uses its own duty-hour bands: 500 hours a year for pleasure (300 for mechanical control), 2,000 for light duty, 3,500 for medium duty, and no limit for continuous duty on boxes smaller than ZF's 2000 series. See how much horsepower a 71C or 72C can handle for the ratings themselves.

Where these numbers come from

These tables come from Velvet Drive's own service manuals, owner's manuals, spec sheets and parts catalogs, not from forum estimates. Different documents from different eras sometimes give slightly different numbers for the same part, which is why several tables above show a range or name the specific document. When in doubt, match the document to the tag on your unit, or call us and we'll help sort it out.

Questions about a spec we didn't cover? Call (804) 333-3677, Monday through Friday 9 to 3 Eastern, or email sales@halemarine.com.