1986 70 foot Hatteras Lady T twin Detroit Diesel 12V71TI marine engine survey

Premium Marine Engine Survey Report
M/V LADY T

1986 • Approximately 70 FT Hatteras • Twin Detroit Diesel 12V71TI Marine Diesel Engines

Marine Engine Survey

Conducted by: Jeff Lendall & Sons — 805 Marine Diesel Mechanic

This survey documents visual inspection, operational testing, sea trial performance, turbocharger condition, Twin Disc MG-514C marine-gear findings, laboratory oil analysis, propulsion drivetrain observations, cooling-system condition, generator observations, bow-thruster findings, and estimated repair requirements aboard M/V Lady T.

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Detroit Diesel 12V71TI
Twin Disc MG-514C
Sea Trial
Oil Analysis
Cooling System Review

Executive Survey Summary

As a result of my investigation, marine engine survey, visual inspection, operational testing, cooling-system pressure testing, laboratory oil analysis, and sea trial, my opinion is that the overall machinery rating is GOOD — WITH SIGNIFICANT REPAIRS RECOMMENDED.

The engine room and Detroit Diesel engines appear generally clean and well maintained. The primary repair concerns are centered around the four turbochargers, both Twin Disc MG-514C marine gears, propulsion shaft/cutlass-bearing condition, and seawater pumps.

Overall Engine Operation:
GOOD
Marine Gear Oil Analysis:
FAILED — Water in Both Gears
Primary Concerns:
Marine Gears, Turbos, Drivetrain & Seawater Pumps
Critical Marine Gear Finding: Laboratory oil analysis identified water contamination in both Twin Disc MG-514C marine gears. Both oil samples failed laboratory analysis. Both marine gears also produced a noticeable clunk during reverse engagement. Both should be professionally evaluated internally and the source of water contamination identified.
Important Turbocharger Finding: During WOT testing, significant black exhaust smoke was observed. Subsequent inspection identified oil leakage associated with turbocharger seal areas entering the exhaust system. Replacement of all four turbochargers is recommended.

Marine engine survey condition rating meter

System Condition Matrix

System Condition
Fuel System Excellent
Main Engine Lubrication System Excellent
Cooling System Operating satisfactorily; seawater pumps require replacement due to seal leakage
Turbocharger System Replacement Recommended
Port Twin Disc MG-514C Marine Gear FAILED OIL ANALYSIS — water contamination
Starboard Twin Disc MG-514C Marine Gear FAILED OIL ANALYSIS — water contamination
Marine Gear Reverse Engagement Abnormal clunk — internal inspection recommended
Shaft / Cutlass-Bearing Area Movement observed — further inspection required
Steering & Rudders Very Good
Northern Lights Generator Operational — seawater pump leaking at seal
Bow Thruster Operational — zinc and bearing service required

Vessel & Engine Identification

Vessel M/V LADY T
Builder Hatteras
Year 1986
Length Approximately 70 FT
Specification Port Engine Starboard Engine
Engine Make Detroit Diesel Detroit Diesel
Engine Model 12V71TI 12V71TI
Engine Type Inboard Inboard
Power 650 HP 650 HP
Fuel Type Diesel Diesel
Hours 4,670 4,040
Marine Gear Twin Disc MG-514C Twin Disc MG-514C
Gear Oil Analysis FAILED — Water Contamination FAILED — Water Contamination
Northern Lights Generator — 2015:
Model: PX-320K2
Serial Number: K64553
Hours: 287
Kilowatts: 20 kW

Detroit Diesel 12V71TI Operational Findings

Engine Synchronization: Engine synchronization appeared normal with no excessive load imbalance observed.
Cold Start: Both engines started promptly without excessive crank time or abnormal smoke.
Coolant Temperature: Engine coolant temperatures remained within normal operating range during cruise and WOT testing.
Oil Pressure Under Load: Approximately 60 PSI port and 60 PSI starboard during WOT testing.
Wide Open Throttle: Both engines reached approximately 2100 RPM.
Turbocharger / Exhaust Condition: Oil leakage was observed from turbocharger seal areas with evidence of oil entering the exhaust system. Significant black exhaust smoke was evident at WOT. Replacement of all four turbochargers is recommended.
Twin Disc MG-514C Marine Gears: Both gears operated smoothly in forward, but a noticeable clunk was heard and felt during reverse engagement. Both gears failed oil analysis due to water contamination. Internal inspection and determination of the water-entry source are recommended.

Visual Engine Inspection Findings

Fuel Filtration: Racor Twin Turbine Series 900 assemblies were inspected. No water was observed and the assemblies appeared serviceable.
Marine Gears: Both Twin Disc MG-514C gears exhibited reverse-engagement clunking and failed laboratory oil analysis due to water contamination.
Seawater Pumps: Leakage was observed at the seal/weep-hole areas on both Detroit Diesel seawater pumps and the Northern Lights generator seawater pump. Replacement of all three is recommended.
Heat Exchangers: Performance appeared satisfactory and coolant temperatures remained normal.
Engine Oil Coolers: Inlet and outlet temperatures appeared within expected operating parameters.
Cooling-System Pressure Testing: Both main engines and the generator were tested to approximately 25 PSI. All three systems passed.
Hoses & Clamps: Generally serviceable where visible, with double-clamped hose connections.
Propulsion Shaft / Cutlass Bearing: Movement was observed. Further inspection of bearing wear, shaft condition, couplings, and alignment is recommended.
Bow Thruster: Operated satisfactorily during docking; shaft play was observed during haul-out. Bearing replacement and zinc service are recommended.

Sea Trial Report

Sea Trial Item Observation
Cold Start Both engines started promptly without excessive cranking or abnormal smoke.
WOT Engine Speed Approximately 2100 RPM on both engines.
Exhaust Appearance Significant black smoke at WOT; turbocharger oil leakage observed.
Cooling Water Discharge Strong and consistent from both main engines and generator.
Coolant Temperature Within normal limits during cruise and WOT.
Oil Pressure Approximately 60 PSI on both engines under full load.
Marine Gear Forward Operation Both gears operated smoothly in forward.
Marine Gear Reverse Operation Noticeable clunk in both gears.
Marine Gear Oil Analysis Both gears FAILED due to water contamination.
Bow Thruster Operational during docking; shaft play observed during haul-out.
Sea Trial / Oil Analysis Concern: Reverse-engagement clunking combined with confirmed water contamination in both Twin Disc MG-514C gears warrants internal inspection of both units.

Oil Analysis Samples

The following laboratory samples are included in the survey record.

Component Finding Laboratory Report
Starboard Twin Disc MG-514C FAILED — WATER CONTAMINATION STARBOARD GEAR REPORT
Port Twin Disc MG-514C FAILED — WATER CONTAMINATION PORT GEAR REPORT
Detroit Diesel Starboard Engine Sample obtained STARBOARD ENGINE REPORT
Detroit Diesel Port Engine Sample obtained Sample Obtained
Northern Lights Generator Sample obtained GENERATOR REPORT
Marine Gear Oil Analysis: Water contamination was detected in both Twin Disc MG-514C marine gears. Inspection should include oil coolers, cooling-water interfaces, seals, breathers, bearings, clutch components, gears, shafts, and internal surfaces as appropriate during disassembly.

Detroit Diesel 12V71TI Marine Engine Survey Summary

As a result of my investigation, marine engine survey, laboratory oil analysis, operational testing, cooling-system pressure testing, and by virtue of my experience, my opinion is OVERALL MACHINERY RATING: GOOD — WITH SIGNIFICANT REPAIRS RECOMMENDED. The engine room and main engines appear generally clean and well maintained.

The Detroit Diesel 12V71TI engines showed favorable cold starting, strong oil pressure under load, normal coolant-temperature performance, acceptable synchronization, and the ability to reach approximately 2100 RPM during WOT testing.

The primary mechanical concerns are the four turbochargers and both Twin Disc MG-514C marine gears. Significant black exhaust smoke and turbocharger oil leakage were observed during WOT testing. Both marine gears produced a noticeable clunk during reverse engagement and subsequently failed laboratory oil analysis because water was detected in both gear-oil samples.

Additional service findings include propulsion shaft/cutlass-bearing movement, leaking seawater-pump seals on both Detroit Diesel engines and the Northern Lights generator, exhaust-manifold gasket service, sea-strainer maintenance, and bow-thruster bearing and zinc service.

Clean Detroit Diesel 12V71TI engine room aboard Hatteras Lady T during marine engine survey

Engine room clean and tidy, generally well maintained.

WOT Test — Both Engines Reached Approximately 2100 RPM

During the initial WOT test, significant black exhaust smoke raised concern regarding turbocharger and exhaust condition. Further observation from the engine room and subsequent inspection identified oil leakage associated with turbocharger seals entering the exhaust system.

Turbocharger Oil Leakage — Port & Starboard Engines

Oil was observed entering the exhaust-manifold area from a turbocharger on each engine. Based on the overall condition and WOT exhaust behavior, replacement of all four turbochargers is recommended.


Detroit Diesel 12V71TI seawater pump showing seal leakage during Hatteras Lady T survey

Seawater pump showing evidence of seal leakage. Both Detroit Diesel main-engine seawater pumps require replacement.
Hatteras Lady T propulsion shaft and cutlass bearing inspection

Movement observed between the propulsion shaft and cutlass-bearing area. Further drivetrain inspection is recommended.

Recommendations & Ballpark Estimate to Repair Mechanical Issues

Recommended Scope: Repair the major marine-gear, drivetrain, turbocharger, cooling-system, exhaust, and seawater-system deficiencies identified during this survey. The following figures are preliminary budgetary allowances and are not fixed-price quotations.
Recommended Repair / Service Ballpark Estimate
Twin Disc MG-514C Marine Gears
Remove, professionally rebuild, and reinstall both existing marine gears; determine the source of water contamination; inspect marine-gear oil coolers and associated cooling-water interfaces; reconnect associated systems; check alignment; dock test and sea trial.
$53,000–$67,000
Replace Four Detroit Diesel Turbochargers
Replace all four turbochargers, including removal, installation, associated gaskets, seals, hoses, clamps, and operational testing.
$22,000
Port Detroit Diesel Seawater Pump
Replacement pump $1,465 plus approximately 3 hours labor.
Included Below
Starboard Detroit Diesel Seawater Pump
Replacement pump $1,465 plus approximately 3 hours labor.
Included Below
Northern Lights Generator Seawater Pump
Replacement pump $720 plus approximately 2 hours labor.
Included Below
Four Exhaust Manifold Gaskets
Replace all four gaskets and inspect sealing surfaces and associated hardware.
$558 Parts + 8 Hours Labor
Sea Strainer Maintenance
Disassemble, clean, inspect, service, and reassemble applicable main-engine and generator seawater strainers.
6 Hours Labor + Materials

Additional Parts & Labor Breakdown

Additional Parts / Labor Item Cost
Detroit Diesel seawater pumps — $1,465 x 2 $2,930
Northern Lights generator seawater pump $720
Four exhaust manifold gaskets $558
Labor — 22 hours x $175/hr $3,850
Sea-strainer seals, O-rings, gaskets, hoses, clamps, and miscellaneous materials As Required
Known Additional Parts & Labor Subtotal $8,058 + Materials

OPTION 1 — Marine Gear Rebuild & Turbocharger Replacement

Rebuild Both Twin Disc MG-514C Marine Gears:
$53,000–$67,000

Replace All Four Turbochargers:
$22,000

Additional Identified Maintenance:
$8,058 + materials


ESTIMATED TOTAL: $83,058–$97,058

Plus additional materials and excluded repairs.

Marine Gear Replacement Alternative

As an alternative to rebuilding the existing Twin Disc MG-514C marine gears, replacement with rebuilt/remanufactured units may be considered.

A budgeting reference of approximately $32,224.50 per marine gear represents approximately $64,449 for two units, before removal, installation, freight, core handling, fluids, alignment, associated repairs, and testing.

Estimated complete two-marine-gear replacement project: $85,000–$105,000.

Four Turbocharger Replacement Allowance

Replacement of all four Detroit Diesel marine turbochargers is budgeted at a straight $22,000.

This allowance is used consistently in both repair options and includes the specified replacement work. The previous turbocharger rebuild and replacement price ranges have been removed from the combined budgets.

Total Turbocharger Replacement Allowance: $22,000.

OPTION 2 — Marine Gear Replacement & Turbocharger Replacement

Replace Both Twin Disc MG-514C Marine Gears:
$85,000–$105,000

Replace All Four Turbochargers:
$22,000

Additional Identified Maintenance:
$8,058 + materials


ESTIMATED TOTAL: $115,058–$135,058

Plus additional materials and excluded repairs.

Estimate Note: These repair-cost figures are preliminary survey budgeting allowances. The extent of internal water-related marine-gear damage cannot be established until the gears are removed and inspected. Major hard-part damage, marine-gear cooler failure, shaft or coupling repairs, alignment corrections, yard charges, freight, core issues, structural access requirements, or additional deficiencies may increase final repair costs.

Priority Recommendations

1. Both Twin Disc MG-514C Marine Gears — HIGH PRIORITY:
Both gears failed laboratory oil analysis due to water contamination and both exhibited abnormal reverse engagement. Determine the water-entry source and internally inspect both marine gears.
2. Replace Four Detroit Diesel Turbochargers — HIGH PRIORITY:
Replace all four turbochargers due to oil leakage and significant black exhaust smoke during WOT operation. Estimated replacement allowance: $22,000.
3. Replace Three Seawater Pumps:
Replace both Detroit Diesel main-engine seawater pumps and the Northern Lights generator seawater pump.
4. Propulsion Shaft / Cutlass-Bearing Inspection:
Determine actual bearing wear, shaft condition, coupling condition, and driveline alignment.
5. Exhaust Manifold Gasket Service:
Replace the four identified exhaust-manifold gaskets and inspect sealing surfaces and hardware.
6. Sea-Strainer Maintenance:
Disassemble, clean, inspect, service, and reassemble applicable main-engine and generator seawater strainers.
7. Bow Thruster:
Inspect and replace bearing components as required and replace the zinc anode.

Items Requiring Additional Inspection

Internal Marine Gear Condition:
The failed laboratory samples establish water contamination in both marine gears but do not establish the complete extent of internal damage. Bearings, gears, clutch components, shafts, seals, oil coolers, lubricant passages, and internal surfaces should be inspected during removal/disassembly.
Propulsion Shaft / Cutlass Bearing:
Movement was observed in the propulsion shaft/cutlass-bearing area. Bearing wear, shaft condition, coupling condition, and driveline alignment should be determined during further inspection.
Bow Thruster Bearings:
The bow thruster operated during docking; however, shaft play was identified during haul-out inspection. Bearing replacement is recommended.
Bow Thruster Zinc:
Zinc-anode service is recommended while the bow thruster is being serviced.
Budget Exclusion:
Shaft, cutlass-bearing, coupling, propeller, bow-thruster bearing, unforeseen marine-gear hard-part damage, marine-gear cooler repairs, and other unidentified repairs are not included in the combined estimates because the complete repair scope has not yet been established.

Final Surveyor Conclusion

Based on visual inspection findings, operational testing, cooling-system pressure testing, laboratory oil analysis, machinery observations, and sea-trial performance, the twin Detroit Diesel 12V71TI engines aboard M/V Lady T demonstrated several favorable basic operating characteristics.

Both engines started promptly from cold, maintained approximately 60 PSI oil pressure during WOT operation, maintained coolant temperatures within normal operating limits, and reached approximately 2100 RPM during wide-open-throttle testing.

The engine room and main engines were generally clean and appeared well maintained.

The principal mechanical concerns are the condition of the four turbochargers, the failed oil-analysis results for both Twin Disc MG-514C marine gears due to water contamination, the reverse-engagement clunk observed in both gears, propulsion shaft/cutlass-bearing movement, seawater-pump leakage on both Detroit Diesel engines and the Northern Lights generator, exhaust-manifold gasket service, sea-strainer maintenance, and bow-thruster bearing wear.

Primary Marine-Gear Concern:
Both Twin Disc MG-514C marine gears failed laboratory oil analysis because water was detected in the lubricant. Combined with the abnormal reverse-engagement clunk, this represents a significant drivetrain concern. Both marine gears should be internally evaluated before they can be considered acceptable for continued service.
Primary Turbocharger Concern:
Turbocharger oil leakage and significant black exhaust smoke observed during WOT testing indicate that all four turbochargers require replacement. The estimated replacement allowance for all four units is $22,000.
Primary Drivetrain Concern:
The clunking condition heard and felt when both Twin Disc MG-514C marine gears were shifted into reverse, together with movement observed in the shaft/cutlass-bearing area and the failed marine-gear oil-analysis results, requires additional investigation before the drivetrain can be considered fully serviceable.

Final Machinery Assessment

Overall Machinery Condition:
GOOD — WITH SIGNIFICANT REPAIRS RECOMMENDED


OPTION 1 — Marine Gear Rebuilds + Four Turbocharger Replacements:

$83,058–$97,058

OPTION 2 — Marine Gear Replacements + Four Turbocharger Replacements:

$115,058–$135,058

Both options exclude additional materials and repairs not yet fully defined.

Professional Survey Notes

NOTICE:

The following statements limit the liability of the undersigned and set ethical standards associated with this report. Use of this report for any purpose constitutes acceptance of the following:

NOTE A: This report is issued without prejudice and is the property of the Requestor as listed above. Any use or distribution by another party is prohibited and shall render this report invalid.

NOTE B: This report is issued subject to the understanding that the undersigned surveyor is not responsible for error, omission, negligence, or misstatement. This report is a statement of my opinion based on the conditions as I found them. It is not a warranty, express or implied.

NOTE C: This survey represents conditions observed during inspection and sea trial. Components that were concealed, inaccessible, internally damaged, or not reasonably inspectable without disassembly may contain conditions that were not visible at the time of inspection.

NOTE D: Repair estimates contained in this report are provided for general budgeting purposes and may change following component disassembly, additional inspection, parts research, laboratory findings, or discovery of additional deficiencies.

Survey Conducted By

Owner / Surveyor: Jeff Lendall

Jeff Lendall & Sons
805 Marine Diesel Mechanic