Viking 40 Convertible / 40 Sedan
Built 1973–1982 by Viking Yachts
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About the Viking 40 Convertible / 40 Sedan
Researched from public sources for this model. Any individual boat may have been modified or repowered — confirm before relying on any figure.
- Built
- 1973–1982
- Builder
- Viking Yachts
- Length
- 40.33 ft
- Beam
- 14.5 ft
- Draft
- 3.5 ft
- Displacement
- 30,000 lb
- Hull
- fiberglass-cored
- Hull / keel
- planing
- Propulsion
- inboard
- Fuel
- varies by year
- Water
- 90 gal
- Water heater
- 12 gal · standard
- Generator
- standard
- Bow thruster
- not fitted
- Stern thruster
- not fitted
Tank capacities — where the figures come from
-
Fuel varies by year
“Fuel capacity, std. 350 gal. (1,324.9 l)” — brochure (40 Convertible brochure (undated)), vikingyachts.com · “Fuel Capacity - 300 Gal. (1136 liters)” — brochure (40 Sedan Fisherman brochure (undated)), vikingyachts.com · “The fuel capacity is 300 gallons” — broker listing, denisonyachtsales.com · “Fuel capacity is 350 gallons” — search excerpt, denisonyachtsales.comViking's two brochures differ: the 40' Sedan Fisherman sheet lists 300 gal, the 40' Convertible sheet 350 gal. Neither is dated, so which years had which tank isn't settled (the Sedan sheet looks earlier). That explains the broker reviews' 300 vs 350.
-
Water 90 gal
“Water capacity, std. 90 gal. (340.9 l)” — brochure, vikingyachts.com · “Water Tank - 90 Gal. (340.7 liters)” — brochure, vikingyachts.comSame in both Viking brochures.
-
Holding unknown
The Convertible brochure specifies a Monomatic (recirculating) toilet and the Sedan sheet an electric toilet; neither gives a holding capacity.
-
Water heater 12 gal · standard
“Hot water heater, 12 gal. capacity” — brochure, vikingyachts.com · “Hot Water Heater — 12 Gal. (45.4 liters)” — builder, vikingyachts.comBoth Viking documents (40 Convertible brochure and 40 Sedan Fisherman specifications) list a 12 US gal water heater in the standard water system, separate from the 90 gal water tank. Heating method not stated.
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 not fitted
Viking's 40 Convertible and 40 Sedan Fisherman specification sheets list standard equipment with no thruster, but they aren't full option lists, so our earlier figure of none stays unconfirmed.
-
Stern thruster not fitted
Same builder sheets; no thruster listed, no full option list found.
-
Steering unknown
Neither Viking 40 specification sheet states the steering system (the later 35 Convertible sheet lists hydraulic steering, but that doesn't carry over). No other source was found.
Thrusters and steering are often replaced — check the units on your boat before ordering parts.
Over 400 sold. Steel engine mounts. Most were diesel powered. Generator moved from under the cockpit to the engine room in 1980; teak interior from 1982. Fuel 300 or 350 gal. Build count (approximate, not stored): HMY: over 400 sold.
Engines fitted
-
Crusader gas V8 (350 hp) — 350 hp, gas, twin
standard
HMY: gas power was standard but most boats got diesels. Denison: twin 350 hp Crusader gas engines were Viking's standard.Sources: hmy.com · denisonyachtsales.com
-
Detroit Diesel 6-71N (J&T) — 310 hp, diesel, twin
factory option
HMY: the popular 310 hp J&T 6-71Ns cruise about 20 kn. J&T was a Detroit Diesel marinizer; Denison lists General Motors (Detroit) among the diesel options.Sources: hmy.com · denisonyachtsales.com
-
Detroit Diesel 6-71TI — 410 hp, diesel, twin
factory option
HMY: a pair of 410 hp 6-71TIs cruise at 23 kn.Sources: hmy.com
-
Caterpillar — 300 hp, diesel, twin
factory option
HMY: 300 hp Cats cruise around 20 kn; model not named.Sources: hmy.com · denisonyachtsales.com
-
Cummins — diesel, twin
factory option
Denison lists Cummins among the factory diesel options (options overall ranged 225-410 hp); model and hp not given.Sources: denisonyachtsales.com
- Detroit Diesel 6-71N — 310 hp, diesel factory option
Boats of the same model can differ — check which engines yours actually has before ordering parts.
Generator
standard
“Generator, 6.5KW gasoline, w/muffler” — brochure, vikingyachts.com · “120 Volt 6 1/2 KW AC Generator; Generator Muffler” — builder, vikingyachts.com
Standard on both the Convertible and Sedan per Viking's own documents; make not named. Our earlier note that the generator moved from under the cockpit to the engine room in 1980 isn't covered by either document, so it isn't confirmed.
-
Generator (make not stated) — 6.5 kW, gas
standard
Viking lists a 6.5 kW gasoline generator as standard with the standard twin 350 hp Crusader gasoline engines but does not name the make.“Generator, 6.5KW gasoline, w/muffler” — brochure, vikingyachts.com · “120 Volt 6 1/2 KW AC Generator” — builder, vikingyachts.com
Generators are often replaced or added — check the unit's own plate before ordering parts.
Manuals and brochures online
- Brochure Viking 40' Convertible brochure with specifications (Viking Yacht Co.) — vikingyachts.com
- Spec sheet Viking 40' Sedan Fisherman specifications (Viking Yacht Co.) — vikingyachts.com
Hosted by the builder or an owners' association; they own the copyright.
Known problems for this model
-
Early balsa-cored hullsides hull
One of the first production boats with balsa-cored hullsides; at this age a moisture survey of the topsides is prudent.hmy.com
Engines & parts
Crusader 350 / 454 inboard gas V8 parts: good
Factory standard engine — you entered “Crusader gas V8 (350 hp)”
GM-based inboard engines; Crusader (now part of Pleasurecraft Marine Engine Co.) still publishes illustrated parts manuals and sells through distributors. Go2marine stocks Crusader manifolds, risers, raw water pumps and ignition parts; Osco and Barr make aftermarket manifolds, and new GM/Crusader base engines are sold by rebuilders.
Parts sources: Crusader Engines, Go2marine (Crusader parts), 1-800-RUNS-NEW (GM & Crusader base engines)
Common problems (1)
-
Clogged or failing manifolds/risers exhaust
Owners find individual risers running much hotter than the others (a sign of internal blockage) and debate replacing vs. flushing; Osco manifolds are often preferred as closest to OEM.marineengine.com · marineengine.com
Maker’s service schedule (14)
| Engine oil & filter change 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 50 hrs or 1 yr | “Change engine oil and filter — After 1st 25 Hrs / Every 50 Hours of Operation / Once Each Year” — manufacturer (2013), crusaderengines.com |
| Fuel filters & water separator 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 50 hrs or 1 yr | “Fuel Filters - Service or replace — After 1st 25 Hrs / Every 50 Hours / Once Each Year” — manufacturer (2013), crusaderengines.com |
| Raw-water pump impeller 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 100 hrs or 1 yr | “Cooling System - Inspect/Replace raw water pump impeller — Every 100 Hours of Operation / Once Each Year” — manufacturer (2013), crusaderengines.com |
| Drive belts inspect / replace 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 100 hrs or 1 yr | “Drive Belt - Inspect condition and check tension — After 1st 25 Hrs / Every 100 Hours / Once Each Year” — manufacturer (2013), crusaderengines.com |
| Spark plugs inspect / replace 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 100 hrs or 1 yr | “Ignition System and Spark Plugs - Clean and inspect condition — After 1st 25 Hrs / Every 100 Hours / Once Each Year” — manufacturer (2013), crusaderengines.com |
| Exhaust mixing elbow inspection 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 100 hrs or 4 mo | “Exhaust System - Check condition and tightness of all hose clamps — After 1st 25 Hrs / Every 100 Hours(1) / Once Each Ye” — manufacturer (2013), crusaderengines.com |
| Coolant replacement & freeze-point test 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 5 yrs | “Fresh-water cooled models - Change coolant — Every five years” — manufacturer (2013), crusaderengines.com |
| Engine pencil zincs 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 1 mo | “Zinc Anodes - Heat exchanger and cooler - check condition — Every 30 days” — manufacturer (2013), crusaderengines.com |
| Transmission fluid change 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 1 yr | “Transmission and "V" Drive - Change fluid and clean strainer, if equipped — After 1st 25 Hrs (Hurth Only) / Once Each Ye” — manufacturer (2013), crusaderengines.com |
| Flame arrestor & crankcase ventilation - clean and inspect 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 100 hrs or 1 yr | “Flame Arrestor and Crankcase Ventilation System - Clean and inspect — Every 100 Hours / Once Each Year” — manufacturer (2013), crusaderengines.com |
| Engine alignment check 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 1 yr | “Engine Alignment - Check and adjust if necessary — After 1st 25 Hrs / Once Each Year” — manufacturer (2013), crusaderengines.com |
| Inspect all hoses (and cooling hose clamps) 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 100 hrs or 1 yr | “Hoses (all) - Inspect for cracks, swelling, weather checking or other signs of deterioration — Every 100 Hours / Once Ea” — manufacturer (2013), crusaderengines.com |
| Shift & throttle cable linkage - inspect and lubricate 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 100 hrs or 4 mo | “Shift and Throttle Cable Linkage - Inspect and lubricate — Every 100 Hours(1) / Once Each Year” — manufacturer (2013), crusaderengines.com |
| Electrical system - check connections and wiring 2013 MPI 5.0L/5.7L (350 CID)/6.0L | 50 hrs or 2 mo | “Electrical System (complete) - Check for loose or dirty connections and damaged wiring — Every 50 Hours(2) / Once Each Y” — manufacturer (2013), crusaderengines.com |
Service part numbers (18)
| Oil filter remote-mounted oil filter (MP7.4L and 2013 5.0/5.7/6.0L MPI) |
Crusader 22679 | “Oil Filter 22679 (MAINTENANCE ITEM PART NUMBERS)” — manufacturer, crusaderengines.com |
| Fuel filter MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008 |
Crusader 47038 | “Fuel Filter 47038 (MAINTENANCE ITEM PART NUMBERS)” — manufacturer, crusaderengines.com |
| Fuel filter 5.7L (350) MPI with FCC fuel system, 2007 on - 2013 owner manual L510001-13 |
Crusader RP080026 | “Fuel Control Cell (FCC) Fuel Filter Element RP080026” — manufacturer, crusaderengines.com |
| Fuel pre-filter / separator MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008: engine-mounted Racor water-separating filter 47046 |
Crusader 47047 | “25 47047 Element, Racor fuel filter (Not Shown) 1” — manufacturer, crusaderengines.com |
| Fuel pre-filter / separator 5.7L (350) MPI with FCC fuel system, 2007 on - 2013 owner manual L510001-13: primary fuel filter |
Crusader R080033 | “Primary Fuel Filter Element R080033” — manufacturer, crusaderengines.com |
| Raw-water impeller MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008 (raw water pump RA057031) |
Crusader RP061017 Replaces R061017 |
“Replaces Crusader R061017 (Impeller Kit with Gasket & O-Ring | Crusader RP061017)” — dealer, marinepartssource.com · “Replaces Crusader R061017 (Impeller Kit with Gasket & O-Ring | Crusader RP061017)” — dealer, marinesuppliesdepot.com |
| Raw-water impeller 5.7L (350) MPI with FCC fuel system, 2007 on - 2013 owner manual L510001-13 |
Crusader RP061022 | “Impeller , Raw Water Pump (1) RP061022 (ON-BOARD PARTS KIT 5.7L)” — manufacturer, crusaderengines.com |
| Raw-water pump kit MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008 (raw water pump RA057031) |
Crusader 40064 | “40064 Overhaul Kit, Major (includes items 2, 3, 11, 14 and 15)” — manufacturer, crusaderengines.com |
| Drive belt MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008: alternator drive |
Crusader 98210 | “Alternator Drive Belt 98210” — manufacturer, crusaderengines.com |
| Drive belt MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008: raw water pump drive |
Crusader 10258 | “Raw Water Pump Drive Belt 10258” — manufacturer, crusaderengines.com |
| Drive belt 5.7L (350) MPI with FCC fuel system, 2007 on - 2013 owner manual L510001-13, left-hand (LH) rotation: serpentine |
Crusader R066028 | “Belt , Serpentine (1) R066028 (ON-BOARD PARTS KIT 5.7L (LH))” — manufacturer, crusaderengines.com |
| Drive belt 5.7L (350) MPI with FCC fuel system, 2007 on - 2013 owner manual L510001-13, right-hand (RH) rotation: serpentine |
Crusader R066029A | “Belt , Serpentine (1) R066029A (ON-BOARD PARTS KIT 5.7L (RH))” — manufacturer, crusaderengines.com |
| Spark plug MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008: platinum plug |
Crusader 49078 × 8 | “Spark Plugs (platinum) 49078” — manufacturer, crusaderengines.com |
| Spark plug 5.7L (350) MPI with FCC fuel system, 2007 on - 2013 owner manual L510001-13: platinum plug set |
Crusader RP030010 | “Spark Plug , Set, (Platinum) (1) RP030010 (ON-BOARD PARTS KIT 5.7L)” — manufacturer, crusaderengines.com |
| Thermostat MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008: raw-water (standard) cooling, 143 F |
Crusader R026002E | “6 R026002E Thermostat (143-degree) 1 (Raw Water Cooling Components - Figure 18)” — manufacturer, crusaderengines.com |
| Thermostat MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008: fresh-water (closed) cooling kit, 170 F |
Crusader 98203 | “5 98203 Thermostat (170-degree) 1 (Fresh Water Cooling Components 1)” — manufacturer, crusaderengines.com |
| Zinc / anode MP7.4L / MP454 XLi (454 MPI) - illustrated parts manual L510008: oil cooler / transmission cooler / heat exchanger |
Crusader R168005 | “24 R168005 Zinc, sacrificial 1 (Raw Water Cooling Components - Figure 18)” — manufacturer, crusaderengines.com |
| On-board spare parts kit (belt, cap, rotor, fuses, relays, plugs, impeller, fuel filters) 5.7L (350) MPI with FCC fuel system, 2007 on - 2013 owner manual L510001-13, LH rotation |
Crusader RK173089D-07 | “ON-BOARD PARTS KIT 5.7L (LH) 2007 TO PRESENT, FCC FUEL SYSTEM RK173089D-07” — manufacturer, crusaderengines.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.
Detroit Diesel 6-71 (inline, N / T / TI) parts: good
Factory optional engine — you entered “Detroit Diesel 6-71N (J&T)”
Two-stroke 71-series engine with a huge commercial, bus and marine population; basic engine parts and complete overhaul kits (liners, pistons, injectors, blowers, bearings, gaskets) are cheap and widely available from Diesel Pro Power, Highway and Heavy Parts and others. Some marine-specific parts (coolers, manifolds) are harder to find. Designed to be rebuilt in-frame repeatedly; naturally aspirated engines with good care have been reported past 15,000 hours, turbo versions more like 3,000–5,000.
Parts sources: Diesel Pro Power (Detroit Diesel parts), Highway and Heavy Parts (Series 71)
Common problems (2)
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Oil leaks engine
Owners describe 71-series Detroits as habitual oil leakers; chasing leaks with the right gaskets and sealants is a routine topic even on freshly rebuilt engines.trawlerforum.com · cruisersforum.com
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Noise and smoke exhaust
Injector and exhaust noise is loud unless mufflers are well designed, and some smoke is typical of the two-stroke design.trawlerforum.com
Maker’s service schedule (18)
| Engine oil & filter change | 150 hrs | “Industrial & Marine 150 Hours (max. engine oil change interval, fuel sulfur 0 to .50%)” — manufacturer, archive.org |
| Fuel filters & water separator | 300 hrs | “Install new elements every 300 hours or when plugging is indicated (Item 13 fuel strainer and filter)” — manufacturer, archive.org |
| Coolant replacement & freeze-point test | 1,000 hrs | “Clean the cooling system every 1,000 hours using a good radiator cleaning compound” — manufacturer, archive.org |
| Engine pencil zincs | 500 hrs | “Every 500 hours ... remove the zinc electrodes from the inlet side of the raw water pump and the heat exchanger” — manufacturer, archive.org |
| Heat exchanger & oil cooler cleaning | 1,000 hrs | “remove the retaining cover every 1,000 hours and inspect the heat exchanger core” — manufacturer, archive.org |
| Drive belts inspect / replace | 200 hrs | “check the tension of the drive belts every 200 hours” — manufacturer, archive.org |
| Air filter / intake silencer dry-type air cleaner | 1 yr | “Dry type elements should be discarded and replaced with new elements after one year of service or when the maximum allow” — manufacturer, archive.org |
| Transmission fluid change Allison Torqmatic M / MH marine gear | 200 hrs | “Drain the oil every 200 hours and flush the gear with light engine oil (Item 41 Torqmatic marine gear)” — manufacturer, archive.org |
| Clean crankcase breather | 1,000 hrs | “Remove the externally mounted crankcase breather assembly every 1,000 hours and wash the steel mesh pad” — manufacturer, archive.org |
| Inspect blower screen | 1,000 hrs | “Inspect the blower screen and gasket assembly every 1,000 hours” — manufacturer, archive.org |
| Check / clean air box drain tubes | 1,000 hrs | “check for flow of air from the air box drain tubes every 1,000 hours” — manufacturer, archive.org |
| Check thermostats and seals | 5,000 hrs or 1 yr | “Check the thermostats and seals at 5,000 hours or once a year” — manufacturer, archive.org |
| Inspect all hoses | 500 hrs or 1 yr | “all hoses should be thoroughly inspected at least every 500 operating hours ... and/or annually” — manufacturer, archive.org |
| Drain water/sediment from fuel tank | 500 hrs | “Open the drain at the bottom of the fuel tank every 500 hours to drain off any water and/or sediment” — manufacturer, archive.org |
| Coolant filter/conditioner element (if fitted) | 500 hrs | “the filter element should be changed every 500” — manufacturer, archive.org |
| Check emergency (air) shutdown | 700 hrs | “check the operation of the emergency shutdown every 700 hours” — manufacturer, archive.org |
| Check engine and transmission mounts | 2,000 hrs | “Check the engine and transmission mounting bolts and the condition of the mounting pads every 2,000 hours” — manufacturer, archive.org |
| Replace fresh-water pump seal | 6,000 hrs | “Replace the water pump seal after it has been in service for 6,000 hours” — manufacturer, archive.org |
Service part numbers (7)
| Raw-water impeller Detroit raw-water pump with 2 1/2 in. impeller (pumps 5115396 / 23507971) |
Detroit Diesel 5193602 | “Impeller for Detroit Diesel and Volvo Penta Marine Water Pumps 5193602 Impeller with 10 Blades and 12 Spline Drive” — dealer, dieselpro.com · “Detroit Diesel Series 71 Raw Water Pump Impeller, New (5193602)” — dealer, highwayandheavyparts.com |
| Raw-water pump kit pumps 5115396 / 23507971 (2 1/2 in. impeller) |
Detroit Diesel 5197224 | “Detroit Diesel Marine Water Pump repair kit 6V53, 6V71, 6-71, 6V92 5197224P For 2 1/2" impeller height” — dealer, dieselpro.com · “A-5197224 1 1 1 Reconditioning Kit ... Pumps #5115396,#23507971” — dealer, interstate-mcbee.com |
| Raw-water pump kit pumps 5122599 / 23507972 (3 1/2 in. impeller) |
Detroit Diesel 5197222 | “Detroit Diesel Marine Water Pump repair kit for 6-71, 8V71, 8V53, 12V71, 6V92, 8V92 5197222” — dealer, dieselpro.com · “A-5197222 1 1 1 Reconditioning Kit Pumps #5122599,#23507972” — dealer, interstate-mcbee.com |
| Zinc / anode electrode assembly, 2 1/8 in., at raw-water pump inlet |
Detroit Diesel 8517479 | “A-8517479 1 1 1 Electrode Assembly - 2 1/8" L At pump inlet” — dealer, interstate-mcbee.com · “Detroit Diesel Electrode, 2.125" Long (8517479) - In-Line 71 Series Heat Exchangers” — dealer, powerlinecomponents.com |
| Zinc / anode electrode assembly, 3 3/8 in., in heat exchanger |
Detroit Diesel 8515850 | “A-8515850 1 1 1 Electrode Assembly - 3 3/8" L In exchanger” — dealer, interstate-mcbee.com · “Detroit Diesel Zinc Electrode, 3.375" Long (8515850) - In-Line 71 Series Heat Exchangers” — dealer, powerlinecomponents.com |
| Thermostat 173 F non-blocking type |
Detroit Diesel 5172141 | “57 5.2050 5172141 Thermostat Assy.” — manufacturer, tractorparts.com · “Detroit Diesel Thermostat for 371, 471, 671 5172141” — dealer, dieselpro.com |
| Thermostat 170 F full-blocking type (needs seal 5132155) |
Detroit Diesel 23503826 | “A-23503826 1 1 Thermostat 170° F Full blocking use seal” — dealer, interstate-mcbee.com · “Detroit Diesel Thermostat, 170 Deg. (23503826)” — dealer, powerlinecomponents.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 (4)
hmy.com · denisonyachtsales.com · vikingyachts.com · vikingyachts.com
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Other Viking models
- Viking 35 Convertible (1974-85) 1974–1985
Researched from public sources. Spotted an error? The sources are listed above — tell us what they got wrong.