NOAA Standard Specification AMC-233-1A Overhaul of Diesel Engines.pdf

AMC-233-1A

AUGUST 1995

SUPERSEDING

AMC-233-1

NOVEMBER 1988

NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION (NOAA)

ATLANTIC MARINE CENTER

STANDARD SPECIFICATION AMC-233-1A

OVERHAUL OF DIESEL ENGINES

1. SCOPE. This specification contains the general requirements and procedures to be used in overhauling diesel engines on and for NOAA ships and boats.

2. REFERENCES.

None

3. REQUIREMENTS.

3.1 General. The following requirements apply to all work.

3.1.1 Except as otherwise specified, the contractor shall

provide all labor, material, services, tools, supervision, and technical expertise needed to accomplish the work required by this specification.

3.1.2 All work shall be performed by an authorized repair

facility of the engine manufacturer or under the direct on-site supervision of a factory-trained mechanic currently certified by the engine manufacturer, and shall be performed in such a manner that the manufacturer's warranty on parts and labor is not voided.

3.1.3 Provide and install "mandatory-renewal" parts and

components during the overhaul as required by this specification, the Detail Specification, and other procurement documents.

Renewal of other parts and components determined to be needed may be provided by the government and shall be installed by the contractor. Additional needed parts and components which are not provided by the government will be negotiated by the Contracting Officer as an additional cost to the purchase order or contract.

3.1.4 Except where rebuilt components are authorized or

specified, all components and parts used in the engines shall be new original equipment manufacturer (OEM) non-surplus components and parts. Prior to installing new and rebuilt components and parts, perform visual and dimensional inspections to verify that the components and parts are acceptable for use.

3.1.5 Where rebuilt components are provided (as authorized

or specified), existing components shall be replaced on an exchange basis with components which have been remanufactured at the engine manufacturer’s factory, and the existing components become the property of the contractor in their as-found condition. When factory-remanufactured components are not available, the existing components shall be disassembled, cleaned, inspected, repaired (including renewal of all parts needed), reassembled, and calibrated by the manufacturer's factory or a manufacturer-authorized repair facility. Rebuilt components shall meet the manufacturer's rebuild specifications and shall be restored to a condition of reliability equivalent to new components and parts. The only parts renewal for which additional costs will be negotiated are component bodies and casings.

3.1.6 All work shall be in accordance with the

manufacturer's service, maintenance, and overhaul technical manuals, including all current and applicable amendments and service bulletins. Unless otherwise specified, the contractor shall provide a copy of the applicable manuals, amendments, and service manuals at the job site. All repairs shall be made according to the manufacturer's engine specifications, clearances, tolerances, and procedures.

3.1.7 Disassemble the engine(s), components, and parts to

the extent specified herein and in other procurement documents.

Whenever the extent of disassembly is not specified, disassembly shall be to the extent required to perform the required inspections, repairs and parts renewal.

3.1.8 Thoroughly clean and conduct a thorough visual

inspection of all disassembled parts for cracks, scoring, chipping, pitting, signs of overheating, excessive wear, signs of distress, and other defects which could affect serviceability of the engine.

3.1.9 After inspections and tests have been completed and

prior to reassembling the components, submit a typed report of all inspection findings and test results, including a record of all measurements and readings taken, to the Contracting Officer's Technical Representative (COTR) or other NOAA representative named in the procurement document. Include in the report recommendations for all additional repairs, inspections, tests, and part renewals needed to insure continued reliable service of the engine. Do not proceed with any additional (not covered by scope of previously required work) repairs, inspections, tests, part renewal, or reassembly until authorized by the Contracting Officer or purchasing agent who issued the procurement document.

3.1.10 After the report has been accepted and all

additional work has been completed, reassemble and reinstall all components that were previously disassembled or removed.

3.1.11 Remove and reinstall interferences as required to

accomplish the required work.

3.1.12 Daily clean up all debris incidental to the

performance of the required work. Upon completion of all work, clean all work sites to their as-found condition.

3.2 Major Overhaul. Whenever a major overhaul is required by

the Detail Specifications or other procurement document, the following requirements apply:

3.2.1 Drain and properly dispose of all liquids in the

engines.

3.2.2 Renew all of the following "mandatory-renewal" parts

and components. Where "rebuilt" is added in parenthesis after a component, a rebuilt component may be provided in lieu of a new component:

a. Seals, "o"-rings, and gaskets

b. Bearings and bushings

c. Piston rings (may be part of a cylinder kit)

d. Valve springs and guides

e. Lube oil

f. Hoses

g. Thermostats and water temperature regulators

h. Coolant and non-chromate corrosion inhibitor

i. Filter elements

j. Cylinder heads (rebuilt) (may be part of cylinder kit)

k. Air starters (rebuilt)

l. Fuel injectors (rebuilt)

m. Fuel pumps (rebuilt)

n. Fresh water pumps (rebuilt)

o. Sea water pumps (rebuilt)

p. Lube oil pumps (rebuilt)

q. Turbochargers and blowers (rebuilt)

r. Governors (rebuilt)

3.2.3 Completely disassemble, clean, inspect, test, reassemble, and calibrate the following components, parts, and subassemblies:

a. (moved to section 3.2.2)

b. Cylinder block, except removal of crankshaft is required only if otherwise specified, if necessary to perform specified inspections, or if necessary to renew crankshaft bearings.

c. Piston assemblies and connecting rods

d. Camshafts

e. Manifolds

f. Other components to the extent required to perform the required inspections, tests, and repairs, and to the extent required to renew parts and components.

3.2.4 Perform a hydrostatic test of the block, liners, and

water-cooled manifolds at pressures recommended by manufacturer.

3.2.5 Perform magnetic particle inspections of all liners

and connecting rods.

3.2.6 (deleted)

3.2.7 (relocated to section 3.1)

3.2.8 Conduct a complete dimensional inspection of all

parts which have surfaces subject to wear.

3.2.9 Conduct a complete dimensional inspection of all

pistons and cylinder liners.

3.2.10 Inspect all connecting rods for straightness and

length.

3.2.11 Conduct visual and dimensional inspections of the

crankshaft journals.

3.2.12 Take a complete set of backlash readings on the

camshaft and accessory drive gears. Inspect gears for galling, scoring, pitting, excessive wear, and other defects which could affect serviceability.

3.2.13 Refill the coolant and lube oil systems. The

coolant system shall be refilled with fresh water and the same type of non-chromate corrosion inhibitor as existing and the lube oil crankcase shall be filled with the same type lube oil as existing.

3.3 Top-End Overhaul. Whenever a top end overhaul is required by the Detail Specifications or other procurement document, the following requirements apply:

3.3.1 Drain and properly dispose of all liquids in the

engines.

3.3.2 Renew all of the following "mandatory-renewal" parts

and components. Where "rebuilt" is added in parenthesis after a component, a rebuilt component may be provided in lieu of a new component.

a. Seals, "o"-rings, and gaskets of all removed and disassembled components and parts

b. Bearings and bushings in disassembled components

c. Lube oil

d. Coolant and non-chromate corrosion inhibitor

e. Filter elements

f. Fuel injector nozzles (rebuilt)

g. Thermostats and water temperature regulators

h. Cylinder heads (rebuilt)

i. Sea water pumps (rebuilt)

3.3.3 Disassemble, clean, inspect, test, reassemble, and

calibrate the following components, parts, and subassemblies:

a. Fresh water pumps

b. Aftercooler cores

c. Air starters

3.3.4 Refill the coolant and lube oil systems. The coolant

system shall be refilled with fresh water and the same type of non-chromate corrosion inhibitor as existing and the lube oil crankcase shall be filled with the same type lube oil as existing.

3.4 Tests. Regardless of the type of overhaul performed, conduct the following tests of the engine after all components have been reassembled.

3.4.1 Test all alarm and shutdown systems prior to starting

the engine. Conduct a preliminary tune-up of the engine.

3.4.2 Monitor engine operations as the ship's engineers

start the engine. Check all joints for leaks.

3.4.3 Perform operational tests of the engine as follows:

a. Operate engines at no-load for one hour and until normal no-load operating temperatures are reached.

b. Increase the load on the engine to 25-percent of its normal operating full load and operate for one-half hour.

c. Increase the load on the engine to 50-percent of its normal operating full load and operate for one-half hour.

d. Increase the load on the engine to 75-percent of its normal operating full load and operate for one hour.

e. Increase the load on the engine to 100-percent of its normal operating full load and operate for two hours.

3.4.4 For main propulsion diesel engines, the ship will

have to get underway for sea trials in order to achieve the specified loads. Provide qualified technicians to ride the ship, observe the operations, make adjustments, and record data.

3.4.5 For electrical generators prime movers, provide

reactive load banks to generate the test loads. Test loads shall be based on the full load capacity of the generator.

3.4.6 During and following each operational test period, make adjustments, correct leaks, and monitor performance of the engine.

3.4.7 Near the end of each operational test period, take

and record the following information:

a. crankcase pressure

b. cylinder exhaust temperatures

c. lube oil temperatures

d. water temperatures

e. fuel oil pressures

f. lube oil pressures

g. water pressures

h. electrical load on generator prime movers

i. exhaust back pressures

j. air box pressure

k. other operating parameters as permitted by installed instrumentation.

3.4.8 Prepare and submit to the COTR or other NOAA

representative named in the procurement document a report of all data taken in conjunction with the test periods. Include in the report the manufacturer's recommended limits for the applicable parameter.

3.4.9 During the performance of the tests, continually

monitor the temperatures and pressures and compare them to the manufacturer's recommended limits. If at any time a temperature or pressure exceeds or falls below the manufacturer's recommended upper or lower limits, the tests shall be stopped and the cause is to be determined. After the cause has been corrected, the tests shall be restarted from the beginning.

3.5 Final Adjustments and Tune-up. After satisfactory

completion of the operational tests, perform the following:

3.5.1 Change the lube oil and lube oil filters on the

engine.

3.5.2 Retorque head bolts and rocker shaft bolts while the

engine is still hot.

3.5.3 Reset valves, reset injectors, and set governor

speed.

3.5.4 Whenever the design of the engine permits, conduct a

compression test on each cylinder. Record readings and submit to the COTR or other NOAA representative named in the procurement.

3.5.5 Conduct final adjustments and tune-ups as required to

provide smooth, efficient, and reliable operation of the engine.

END OF SPECIFICATION