Willard 30 (Mark IV / 30-4)
Built 1976–1988 by Willard
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About the Willard 30 (Mark IV / 30-4)
Researched from public sources for this model. Any individual boat may have been modified or repowered — confirm before relying on any figure.
- Built
- 1976–1988
- Builder
- Willard
- Length
- 30 ft
- Waterline
- 27.5 ft
- Beam
- 10.5 ft
- Draft
- 3.5 ft
- Displacement
- 17,000 lb
- Hull / keel
- full displacement
- Propulsion
- inboard
- Fuel
- 150 gal
- Water
- 100 gal
- Holding
- 25 gal
- Water heater
- engine + AC
Tank capacities — where the figures come from
-
Fuel 150 gal
“FUEL - 150 Gallon in Al min m Tank” — search excerpt (1988 Mark IV), west-yachts.com · “Approximately 100 gallons -- 50 gallons in each of two tanks” — owner's manual (1974 Vega 30 series (predecessor)), willardboats.orgA broker's spec sheet for a 1988 Mark IV supports 150 gal. The builder's 1974 Vega 30 Series owner's manual gives about 100 gal (two 50 gal tanks) for the earlier Nomad, Searcher, Horizon and Voyager boats, so no builder document confirms the Mark IV figure.
-
Water 100 gal
“WATER - 80 Gallon” — search excerpt (1988 Mark IV), west-yachts.com · “Approximately 100 gallons -- 50 gallons in each of two poly-ethylene tanks. Voyager has one 100 gallon tank.” — owner's manual (1974 Vega 30 series (predecessor)), willardboats.orgThe 1974 Vega 30 manual gives about 100 gal, matching our earlier figure, but for the earlier series; a 1988 Mark IV listing says 80 gal. It isn't settled for the Mark IV.
-
Holding 25 gal
“HOLDING TANK - 20 Gallon” — search excerpt (1988 Mark IV), west-yachts.comOne 1988 listing says 20 gal against our earlier 25; the 1974 Vega 30 manual shows no standard holding tank, only space for one.
-
Water heater engine + AC
“Hot & Cold Pressure Water System with Shower ... operated by either running the engine or on 110-volt AC shore power” — owner's manual (1974), willardboats.org · “Water heater (20 A breaker on the A.C. panel, Vega 30 electrical diagram 30AB10)” — owner's manual (1973-1974), willardboats.orgThe builder's April 1974 owner's manual for the Vega 30, the model before this one, describes hot and cold pressure water heated by the engine or 110 V shore power, and its wiring diagram has a water-heater circuit. It predates the 1976-88 Mark IV, so it isn't taken as the standard for this model. No capacity given.
Tanks are often replaced or added on older boats — check the tank labels or a survey for yours.
Thrusters and steering — where this comes from
-
Bow thruster unknown
The 1974 Willard/Vega 30 owner's manual (systems, electrical diagram, spare parts) shows no thruster, and nothing else was found.
-
Stern thruster unknown
Nothing found.
-
Steering unknown
“The steering control is a mechanical system that consists of wheel and gear arrangement that activates a push-pull cable” — owner's manual (1974), willardboats.org · “An additional safety feature on all boats starting with Hull No. 67 provides an emergency steering tiller.” — owner's manual (1974), willardboats.orgThe builder's April 1974 owner's manual for the Vega 30, the model before this one, describes a geared helm driving a push-pull cable to the rudder, with an emergency tiller from hull 67. It predates the 1976-88 Mark IV, so it isn't taken as this model's steering; an owner mentions original cable steering replaced by hydraulics on one boat.
Thrusters and steering are often replaced — check the units on your boat before ordering parts.
Sources disagree on number built — left blank rather than guessed.
Ballasted (about 4,300 lb) canoe-stern full-displacement trawler derived from the Vega 30 Nomad. Engines were V-drive until 1988, when a direct drive replaced them. Burns under 1 gph at 6 knots; range 900-1,000+ nm.
Engines fitted
-
Perkins 4-108 — 50 hp, diesel, single
standard
HMY: single Perkins diesel gives about 900-mile range at 6 kn; V-drive installs until a direct-drive layout in 1988. A 1977 hull is listed with a 50 hp Perkins 4-108 (listing does not say original).Sources: hmy.com · pleasureyachtbrokerage.com
- Perkins single diesel — diesel standard
-
Yanmar model not stated — diesel, single
factory option
HMY says the 30 came with a single Perkins or Yanmar diesel; no Yanmar model or rating found.Sources: hmy.com
- Yanmar single diesel — diesel factory option
Boats of the same model can differ — check which engines yours actually has before ordering parts.
Generator
The 1974 owner's manual and wiring diagram show shore power and a battery charger but no generator.
Manuals and brochures online
- Owner's manual Willard Boat Works Vega 30 Series Owner's Manual (April 1974) (1974) — willardboats.org
- Document Willard Boats owners' site brochures index (Vega 36 brochures, Willard 40 PH brochure 1990) — willardboats.org
Hosted by the builder or an owners' association; they own the copyright.
Known problems for this model
No well-sourced problem reports found yet.
Engines & parts
Perkins 4.108 parts: good
Factory standard engine — you entered “Perkins 4-108”
Out of production but very well supported. Trans Atlantic Diesels (TAD) sells complete aftermarket rebuild kits (pistons, liners, rings, bearings, gaskets, valves, guides, seals), heads, blocks, crankshafts, genuine Perkins camshafts, rebuilt injection pumps and injectors, Jabsco/Sherwood raw water pumps, heat exchangers, starters, alternators and elbows, plus rebuilt exchange engines. The Westerbeke 4-107/4-108 family and some industrial engines share the base design.
Parts sources: Trans Atlantic Diesels (TAD), Foley Engines
Common problems (1)
-
Rear main (crankshaft) seal leak engine
The original rope-type rear seal is notorious for leaking and often starts leaking again a few hundred hours after replacement; Foley sells a nylon/Teflon replacement seal meant to cure it, and owners check the crankshaft sealing surface for pitting.foleyengines.com · boatdesign.net · forums.sailinganarchy.com
Maker’s service schedule (13)
| Engine oil & filter change 4.108(M) marine | 150 hrs or 3 mo | “4.107(M) and 4.108(M) Engines ... Every 150 hours or 3 months (whichever occurs first). Drain and renew lubricating oil” — manufacturer (1973), fujiyachts.net |
| Fuel filters & water separator 4.108(M) marine | 400 hrs or 1 yr | “Every 400 hours or 12 months (whichever occurs first). Renew final fuel filter element.” — manufacturer (1973), fujiyachts.net |
| Air filter / intake silencer 4.108(M) marine | 150 hrs or 3 mo | “Every 150 hours or 3 months (whichever occurs first). ... Clean air intake gauze.” — manufacturer (1973), fujiyachts.net |
| Drive belts inspect / replace 4.108(M) marine | 150 hrs or 3 mo | “Every 150 hours or 3 months (whichever occurs first). ... * Check drive belt tension.” — manufacturer (1973), fujiyachts.net |
| Valve clearance check / adjust 4.108(M) marine | 2,400 hrs | “Every 2,400 hours ... Check and adjust valve tip clearances.” — manufacturer (1973), fujiyachts.net |
| Injector test / service 4.108(M) marine | 2,400 hrs | “Every 2,400 hours ... Service atomisers.” — manufacturer (1973), fujiyachts.net |
| Transmission fluid change 4.108(M) marine | 400 hrs or 1 yr | “Every 400 hours or 12 months (whichever occurs first). ... Change gearbox oil.” — manufacturer (1973), fujiyachts.net |
| Clean water trap 4.108(M) marine | 150 hrs or 3 mo | “Every 150 hours or 3 months (whichever occurs first). ... Clean water trap.” — manufacturer (1973), fujiyachts.net |
| Check engine for oil and water leaks 4.108(M) marine | 150 hrs or 3 mo | “Every 150 hours or 3 months (whichever occurs first). ... Check engine for leakage of oil and water.” — manufacturer (1973), fujiyachts.net |
| Lubricate dynamo rear bush (where fitted) 4.108(M) marine | 150 hrs or 3 mo | “Every 150 hours or 3 months (whichever occurs first). ... Lubricate dynamo rear bush (where fitted).” — manufacturer (1973), fujiyachts.net |
| Check hoses and clips 4.108(M) marine | 400 hrs or 1 yr | “Every 400 hours or 12 months (whichever occurs first). ... Check hoses and clips.” — manufacturer (1973), fujiyachts.net |
| Drain and clean fuel tank 4.108(M) marine | 400 hrs or 1 yr | “Every 400 hours or 12 months (whichever occurs first). ... Drain and clean fuel tank” — manufacturer (1973), fujiyachts.net |
| Examine and service starter motor, generator etc. 4.108(M) marine | 2,400 hrs | “Every 2,400 hours Arrange for examination and service of proprietary equipment, i.e. starter motor, generator, etc.” — manufacturer (1973), fujiyachts.net |
Service part numbers (7)
| Oil filter later engines with spin-on filter |
Perkins 2654403 | “A genuine Perkins 4.108 oil filter - OE Part No. 2654403 ... Fits 4.108 and 4.108M.” — dealer, parts4engines.com · “Filter, Oil late type long 2654403, Length 130mm - 2654403” — dealer, lancingmarine.com |
| Oil filter early engines with element-in-canister filter |
Perkins 26540154 | “A genuine Perkins 4.108 Oil Filter - OE Part No. 26540154” — dealer, parts4engines.com · “Filter, Oil early type 26540154, Length 122mm - 26540154” — dealer, lancingmarine.com |
| Fuel filter cartridge-type filter housing (most engines) |
Perkins 4326658 Replaces 26561117 Also: Delphi (CAV) 296 |
“A genuine Perkins 4.108 fuel filter - OE Part No. 4326658 ... supersedes ... 26561117.” — dealer, parts4engines.com · “Fuel Filter (296) Was 26561117 Now 4326658” — dealer, lancingmarine.com |
| Fuel filter early engines with bowl-type filter housing |
Perkins 30242 | “A genuine Perkins 4.108 fuel filter element - OE Part Number 30242 ... fitted to early Perkins 4.108” — dealer, parts4engines.com · “Filter element, Fuel old type 30242, Length 74mm small element - 30242” — dealer, lancingmarine.com |
| Raw-water impeller Jabsco raw-water pump (3270, 3370-200 or 9970-200) |
Jabsco 1210-0001 | “4.107M / 4.108M / LL 9970-200 040 3/4" BSP Flange SK229 3298 1210-0001” — manufacturer, marineengine.com |
| Raw-water pump kit Jabsco 9970-200 pump |
Jabsco SK229 | “4.107M / 4.108M / LL 9970-200 040 3/4" BSP Flange SK229 3298 1210-0001” — manufacturer, marineengine.com |
| Raw-water pump kit Jabsco 3370-200 pump (obsolete) |
Jabsco SK33 | “4.107M / 4.108M / LL 3370-200 ... 9970-200 SK33 3298 1210-0001” — manufacturer, marineengine.com |
From the engine maker’s parts lists, or two independent parts dealers. Numbers change with serial number and get superseded — check yours before ordering.
Model sources (3)
Other Willard models
- Willard 40 Trawler 1977–2003
Researched from public sources. Spotted an error? The sources are listed above — tell us what they got wrong.