Marine Trader 34 Sedan
Built 1973–2001
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About the Marine Trader 34 Sedan
Researched from public sources for this model. Any individual boat may have been modified or repowered — confirm before relying on any figure.
- Built
- 1973–2001
- Length
- 33.5 ft
- Waterline
- 30.25 ft
- Beam
- 11.75 ft
- Draft
- 3.5 ft
- Displacement
- 19,600 lb
- Hull
- fiberglass
- Hull / keel
- semi-displacement
- Propulsion
- inboard
- Fuel
- 300 gal
- Water
- 150 gal
- Holding
- 40 gal
Tank capacities — where the figures come from
-
Fuel 300 gal
“Fuel Tank Capacity (gal): 300 gallons” — search excerpt, marinesource.comOne listing agrees; no builder figure was found.
-
Water 150 gal
“Water Tank Capacity (gal): 150 gallons” — search excerpt, marinesource.comOne listing agrees; no builder figure was found.
-
Water heater unknown
No builder, importer or review information on the water heater found for the Sedan version.
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
No builder, review or listing source found for the Sedan version. The Double Cabin sister shows thrusters on several listed boats, but that is not carried over here.
-
Stern thruster unknown
Nothing found.
-
Steering unknown
No source describes the steering. One 1973 listing notes dual helm stations but not the mechanism.
Thrusters and steering are often replaced — check the units on your boat before ordering parts.
Beamy solid-fiberglass hull; flybridge and interior revised 1991; teak decks and window frames dropped in 1995. Most have a single 135 hp Lehman (120 hp in older boats) cruising 7 knots at 2-3 gph; optional 210 hp Cummins reaches about 12 knots top. Range over 750 nm.
Engines fitted
-
Ford Lehman SP135 — 135 hp, diesel, single
standard
HMY: most 34 Sedans have a single 135 hp Lehman, cruising about 7 kn at 2-3 gph.Sources: hmy.com
-
Ford Lehman 120 — 120 hp, diesel, single
standard
Standard on older boats per HMY; a 1973 34 Sedan is listed with its single Lehman 120.Sources: hmy.com · boats-from-usa.com
-
Cummins — 210 hp, diesel, single
factory option
HMY: optional 210 hp Cummins gives about 10 kn cruise, 12 kn top. Model not named (likely 6BT family, not confirmed).Sources: hmy.com
Boats of the same model can differ — check which engines yours actually has before ordering parts.
Generator
No builder information was found, and no Sedan boats for sale with generator details turned up.
Known problems for this model
-
Dry rot in glass-over-plywood superstructure deck
The first few years' boats have a plywood superstructure sheathed in glass, which caused widespread rot problems.hmy.com
-
Teak decks and teak window frames leak deck
Teak decks and teak window frames (both eliminated in 1995) often leak into the core and cabin sides.hmy.com
Engines & parts
Ford Lehman 135 / SP135 (2725E) parts: good
Factory standard engine — you entered “Ford Lehman SP135”
Based on the later Ford 'Dover' 2725E 6.2 L naturally aspirated six (Ford built the Dover series 1982–1994, then Otosan/Dovertech to 2005). Parts are sold by the same Lehman specialists as the 120; American Diesel lists spare-parts sheets and Go2marine stocks cooling parts, heat exchangers and elbows for the 135. Do not assume 120 (2715E) and 135 (2725E) internals interchange.
Parts sources: American Diesel Corp, Go2marine (Ford Lehman parts collection)
Maker’s service schedule (14)
| Engine oil & filter change | 200 hrs | “Every 200 hours of operation ..... Change Engine Oil & Filter. And Transmission Oil.” — manufacturer (1987), marinedieselbasics.com |
| Fuel filters & water separator | 200 hrs or 1 yr | “should be replaced once each season or at least each 200 hours (which ever comes first) under normal conditions” — manufacturer (1987), marinedieselbasics.com |
| Raw-water pump impeller | 200 hrs | “Every 200 hours of operation ..... Replace raw water pump impeller.” — manufacturer (1987), marinedieselbasics.com |
| Coolant replacement & freeze-point test | 1,200 hrs | “Every 1200 hours of operation ..... Flush cooling system. Replace anti-freeze.” — manufacturer (1987), marinedieselbasics.com |
| Exhaust mixing elbow inspection | 200 hrs | “Every 200 hours of operation ..... Check exhaust components for leaks.” — manufacturer (1987), marinedieselbasics.com |
| Transmission fluid change Borg Warner gearbox | 200 hrs or 1 yr | “Change oil every 200 hours of operation or at least once each season under normal conditions” — manufacturer (1987), marinedieselbasics.com |
| Transmission fluid change PRM/Newage gearbox | 200 hrs | “After 25 hours running: Drain all oil from the gearbox and refill with one of the recommended lubricants.” — manufacturer (1987), marinedieselbasics.com |
| Transmission fluid change Twin Disc gearbox | 1,000 hrs or 6 mo | “The period between oil changes is 1000 hours of operation or 6 months, whichever occurs first.” — manufacturer (1987), marinedieselbasics.com |
| Check idling speed | 200 hrs | “Every 200 hours of operation ..... Check idling speed, adjust if required.” — manufacturer (1987), marinedieselbasics.com |
| Check coolant and oil hoses | 200 hrs | “Every 200 hours of operation ..... Check condition of all coolant and oil hoses.” — manufacturer (1987), marinedieselbasics.com |
| Check engine mount bolts | 200 hrs | “Every 200 hours of operation ..... Check all engine mount bolts.” — manufacturer (1987), marinedieselbasics.com |
| Replace thermostats | 3,600 hrs | “Every 3600 hours of operation ..... Replace thermostats.” — manufacturer (1987), marinedieselbasics.com |
| Replace Borg Warner transmission oil cooler Borg Warner gearbox | 1,200 hrs | “Suggested replacement time is at 1200 hours.” — manufacturer, img1.wsimg.com |
| Inspect drive damper | 2,500 hrs | “Inspect your drive damper if you have more than 2500 hours on the engine.” — manufacturer, img1.wsimg.com |
Service part numbers (9)
| Oil filter engines built before the 1987 change (original filter) |
Lehman 2N50 | “11 1 2N50 FILTER (Engine Oil Cooler Assembly D196/D197, SP90 / 135)” — manufacturer, marinesurveyorontario.com |
| Oil filter 1987-on engines (larger capacity, revised fitment) |
Lehman 2N53 | “DURING 1987 A NEW OIL FILTER OF LARGER CAPACITY ... THIS IS PART No. 2N53” — manufacturer, marinesurveyorontario.com · “Oil Filter 2N53 LM - P12-R105 P11-88” — dealer, lancingmarine.com |
| Fuel filter | Ford 6149717 × 2 | “2 ALL 2 6149717 FUEL FILTER ELEMENTS” — manufacturer, marinesurveyorontario.com |
| Raw-water impeller | Jabsco 1210-0001 | “Breakdown of 2C48 Pump ... 9 1 1210-0001 IMPELLER” — manufacturer, marinesurveyorontario.com |
| Raw-water pump kit | Jabsco SK239 | “Service Kit SK239 - Comprising Key 7/8/9/17” — manufacturer, marinesurveyorontario.com |
| Drive belt | Lehman 2B209 | “15 1 2B209 VBELT (Alternator Assembly D144, M/N)” — manufacturer, marinesurveyorontario.com · “Alternator Accessory Drive V-Belt 2B209 2B209 - P11-51” — dealer, lancingmarine.com |
| Air filter | Lehman 1F7 | “12 1 1F7 FOAM ELEMENT (Plenum Chamber / Air Filter Assembly D1125, SP135)” — manufacturer, marinesurveyorontario.com · “Air strainer to replace 2H75 & 1F7 (PF136) (Whilst stocks last)” — dealer, lancingmarine.com |
| Zinc / anode | Lehman EM21A | “25A 1 EM21A ZINC ANODE (Heat Exchanger Assembly D882/D883, SP135)” — manufacturer, marinesurveyorontario.com · “Anodes EM21A (Pack of 5) - - P11-18” — dealer, lancingmarine.com |
| Thermostat | Lehman 2C35 | “11 1 2C35 THERMOSTAT ... Modified / 12 1 1541317 GASKET” — manufacturer, marinesurveyorontario.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.
Ford Lehman 120 (6D380 / 2715E) parts: good
Factory standard engine — you entered “Ford Lehman 120”
Marinized by Lehman from the Ford of England 'Dorset' 2715E six-cylinder (380 cu in) industrial/truck diesel; Ford built the Dorset base engines 1964–1984. Base-engine internals interchange with the Ford 2715E, and marine-specific parts (raw water pumps, heat exchangers, injection elbows, gaskets, lift pumps, air filters) are widely stocked. American Diesel Corp (founded by former Lehman people) still sells parts, publishes spare-parts lists and gives technical advice. Rebuilt and used 120s are also sold by salvage yards.
Parts sources: American Diesel Corp, Go2marine (Ford Lehman parts collection), Fred Warner Marine & Outdoors
Common problems (2)
-
Chronic oil leaks engine
Most 120s weep oil somewhere; owners often trace it to the rear of the engine near the heat exchanger (head/head gasket area) or to the drive seals of the gear-driven injection pump. Moderate oil use is treated as normal on these engines.trawlerforum.com · marineengine.com
-
Fuel leaks at injection pump, lift pump and return lines fuel
Slow diesel drips usually come from loose bleed screws or banjo washers, perished rubber injector return hoses, a failing lift-pump diaphragm, or worn internal seals in the Simms or CAV injection pump, which needs a pump shop to overhaul.yescenters.com
Maker’s service schedule (16)
| Engine oil & filter change | 200 hrs | “After first 15 hours running .... 1. Change Engine Oil ... Every 200 hours running ..... 17. Change engine and transmiss” — manufacturer (1986), marinedieselbasics.com |
| Fuel filters & water separator | 200 hrs | “Every 200 hours running ..... 18. Change all engine and fuel oil filters.” — manufacturer (1986), marinedieselbasics.com |
| Change oil in fuel injection pump | 50 hrs | “Every 50 hours running ...... 13. Check cleanliness of intake air filter. 14. Check (exchanger) zinc pencil. 15. Change” — manufacturer (1986), marinedieselbasics.com |
| Transmission fluid change | 200 hrs or 1 yr | “Change oil every 200 hours of operation or at least once each season under normal conditions” — manufacturer (1986), marinedieselbasics.com |
| Valve clearance check / adjust | 400 hrs | “After first 15 hours running .... 3. Adjust valve clearances. ... Every 400 hours running ..... 22. Adjust valve clearan” — manufacturer (1986), marinedieselbasics.com |
| Injector test / service | 400 hrs | “Every 400 hours running ..... 21. Remove and service injectors.” — manufacturer (1986), marinedieselbasics.com |
| Engine pencil zincs | 50 hrs | “After first 15 hours running .... 4. Check (exchanger) zinc pencil. ... Every 50 hours running ...... 14. Check (exchang” — manufacturer (1986), marinedieselbasics.com |
| Drive belts inspect / replace | 200 hrs | “After first 15 hours running .... 5. Adjust belt tension. ... Every 200 hours running ..... 16. Adjust belt tension.” — manufacturer (1986), marinedieselbasics.com |
| Air filter / intake silencer | 50 hrs | “After first 15 hours running .... 8. Check cleanliness of intake air filter. ... Every 50 hours running ...... 13. Check” — manufacturer (1986), marinedieselbasics.com |
| Clean fuel lift pump | 200 hrs | “Every 200 hours running ..... 19. Clean fuel lift pump.” — manufacturer (1986), marinedieselbasics.com |
| Clean injection pump cover filter | 200 hrs | “Every 200 hours running ..... 20. Clean injection pump cover filter.” — manufacturer (1986), marinedieselbasics.com |
| Remove raw water pump and check drive coupling | 400 hrs | “Every 400 hours running ..... 23. Remove raw water pump and check drive coupling. Place dab of grease on coupling halves” — manufacturer (1986), marinedieselbasics.com |
| Adjust idling speed (if required) | 400 hrs | “After first 15 hours running .... 10. Adjust idling speed (if required). ... Every 400 hours running ..... 24. Adjust id” — manufacturer (1986), marinedieselbasics.com |
| Check engine/propeller shaft alignment | 6 mo | “After first 15 hours running .... 9. Check engine/propeller shaft alignment. (twice annually, minimum).” — manufacturer (1986), marinedieselbasics.com |
| Replace Borg Warner transmission oil cooler | 1,200 hrs | “Suggested replacement is at 1200 hours.” — manufacturer, img1.wsimg.com |
| Inspect drive damper | 2,500 hrs | “Inspect your drive damper if you have more than 2500 hours on the engine.” — manufacturer, img1.wsimg.com |
Service part numbers (3)
| Raw-water impeller | Jabsco 1210-0001 | “6D380 5850-0001 040 3/4" NPT Flange SK33 3298 1210-0001” — manufacturer, marineengine.com · “Breakdown of 2C48 Pump ... 9 1 1210-0001 IMPELLER” — manufacturer, marinesurveyorontario.com |
| Raw-water pump kit original 2C45 pump (Jabsco 5850-0001) |
Jabsco SK33 | “6D380 5850-0001 040 3/4" NPT Flange SK33 3298 1210-0001” — manufacturer, marineengine.com |
| Raw-water pump kit Lehman 2C48 replacement pump (Jabsco 10950-2401 type) |
Jabsco SK239 | “Service Kit SK239 - Comprising Key 7/8/9/17” — manufacturer, marinesurveyorontario.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 (2)
Other Marine Trader models
- Marine Trader 34 Double Cabin 1972–2001
- Marine Trader 36 Double Cabin 1975–1993
- Marine Trader 38 Double Cabin 1980–2000
- Marine Trader 40 Sundeck 1983–2000
Researched from public sources. Spotted an error? The sources are listed above — tell us what they got wrong.