Questions and Answers

Frequently Asked Questions from 

Marine Engine Owners and Rebuilders 

about EPA’s Marine Remanufacture 

Program 

The U.S. Environmental Protection Agency (EPA) has adopted a 

new emission control program for marine diesel engines that, for 

the first time, includes emission standards for certain engines already 

in operation. This information sheet answers questions about the 

Marine Remanufacture Program from owners and rebuilders. 

Why did EPA adopt the Marine Remanufacture Program? 

Marine diesel engines are significant contributors to ambient levels of ozone and 

particulate matter (PM) pollution in our nation’s ports and along our rivers and 

coastal waterways. When fully phased-in, EPA’s latest emission standards for new 

engines will result in substantial reductions of nitrogen oxides (NOX) and PM 

emissions from marine vessels. 

Engines built before the new-engine standards take effect, however, will continue 

operating with higher emissions for a long time. Like locomotives, the service life of 

many of these engines can be 30 years or more. The Marine Remanufacture Program 

will provide early air quality benefits by reducing PM emissions from this legacy fleet 

sooner than would be the case through the normal turnover of the fleet to vessels 

with new engines. 

Who should read this fact sheet? 

You should read this fact sheet if you own a propulsion or auxiliary commercial 

marine diesel engine with power at or above 600 kW, manufactured in 1973 or later. 

Office of Transportation and Air Quality 

EPA-420-F-09-003 

February 2009 
You should also read this fact sheet if you are in the business of rebuilding or maintaining such 

marine diesel engines. 

What engines are covered by the Marine Remanufacture Program? 

Your marine diesel engine is covered by the Marine Remanufacture Program if it meets all of the 

following criteria: 

1. It is a commercial marine diesel engine 

2. It was manufactured between 1973 and the last Tier 2 model year. 1 (footnotes) 

3. It has power at or above 600 kilowatts (kW). 2 (footnotes) 

4. It has a displacement of less than 30 liters per cylinder. 3

 (footnotes) 

5. It is installed on a vessel that is flagged or registered in the United States. 

If your engine meets all of the above criteria, it is covered by the Marine Remanufacture 

Program. 

I have a covered engine, what must I do? 

Essentially, if your commercial marine diesel engine is covered by the Marine Remanufacture 

Program, you are required to use a certified remanufacture system when you remanufacture your 

engine, if one is available. These terms and criteria are described in more detail below. 

The decision tree set out in Figure 1 will help you determine if you have to do something under 

the Marine Remanufacture Program. Further information about each of the steps in the decision 

tree, as well as other related information, is provided in the remainder of this information sheet.

Questions and Answers

2 
Figure 1: Marine Remanufacture Program Decision Tree 

NO 

Is my commercial diesel 

engine > 600 kW, 

disp. < 30 L/cylinder and 

on a U.S. flagged vessel? 

Am I replacing or requalifying all 

cylinder liners (either during a 

single maintenance event or over a 

period less than 5 years)? 

NO 

YES 

YES 

If there is no certified kit for 

your engine, you may 

remanufacture without a kit 

for this maintenance event. 

Continue to comply with Part 

94, as applicable, regarding 

engine rebuilds. Review this 

step again at your next 

maintenance event. 

NO 

Is there a certified remanufacturing 

system (“kit”) for my engine? 

Visit EPA’s web site at 

www.epa.gov/otaq/certdata.htm. 

YES 

Stop. Your 

engine is not 

covered by 

this program. 

You are not remanufacturing. 

Keep maintenance records 

and review this step again at 

your next maintenance event. 

Continue to comply with Part 

94, as applicable regarding 

engine rebuilds. 

Questions and Answers

You must remanufacture your 

engine using a certified kit, unless 

one is not “available” or you have 

obtained an exemption as explained 

in this information sheet. 

3 
Questions and Answers

Which scheduled maintenance activities does EPA consider to be 

remanufacturing? 

Remanufacturing, for the purposes of this program, is the removal and replacement - including 

requalifying - of all cylinder liners, either all in a single maintenance event or over a period of 

five (5) years or less. If your cylinder replacement/requalifying schedule takes longer than five 

years, EPA does not consider this to be remanufacturing under this rule. 

As used here, “requalifying” means to inspect a cylinder that may have been recently replaced 

due to a failure, to make sure it qualified for continued use. 

Even though an engine may be “remanufactured” during a rebuild event, not all rebuild events 

and not all maintenance events are considered to be remanufacturing. A rebuild may include 

extensive maintenance that increases the service life of the engine, however it will not be considered to be remanufacturing unless all of the cylinder liners are replaced, either at once or over 

a period of 5 years. 

What is a remanufacture system and how do I know if one has been 

certified for my engine? 

A remanufacture system, commonly referred to as a “remanufacture kit,” is a process for making 

an engine meet certain emission criteria – in this case, a 25 percent reduction in PM emissions. 

The kit may consist of instructions, specifications, limitations and/or engine components. In 

most cases, a kit is expected to consist of “better” versions of parts normally replaced at rebuild 

and should not adversely affect engine reliability, durability, or power. For example, a kit could 

include different fuel injectors or different piston rings to reduce oil consumption. However, in 

some cases it may consist of only instructions for tuning the engine or calibrating adjustable features. If there are several remanufacture systems certified for your engine, you may choose among 

them. 

In addition to engine-based kits, EPA will allow certification of fuel-based kits. These would 

consist of a process of reducing the PM emissions by changing fuel or using a fuel additive. However, owners of engines covered by fuel-based kits will not be required to use them. Instead, they 

may be used as an alternative to the use of certified engine-based kits. 

EPA maintains a list of certified remanufacture systems for marine diesel engines. Visit EPA’s 

web site at www.epa.gov/otaq/certdata.htm to see if a kit has been certified for your engine. 

When is a certified remanufacture kit considered available? 

A remanufacture kit is generally considered to be available 120 days after it is certified. When 

you visit EPA’s web site at www.epa.gov/otaq/certdata.htm, you will see both the certificate issuance date and the date of availability. 

There are two other important criteria that determine if a kit is available for your engine. First, 

you must be able to obtain the kit in a timely manner according to normal remanufacturing 

4 
Questions and Answers

practices. For example, a kit would not generally be considered to be available if you would need 

to remove the engine from your vessel and send it to a factory to be remanufactured. 

Second, the kit must not be too costly, in terms of dollars spent for each ton of PM reduced. 

EPA considers a kit to be too costly if it exceeds a marginal cost threshold of $45,000 per ton of 

PM reduction. The marginal cost of a kit is the added cost of using the kit over and above the 

cost of remanufacturing the engine conventionally, divided by the total amount of PM reductions expected over the useful life of the remanufactured engine. 

We expect that kits will not be certified if they cannot be obtained in a timely manner or if they 

exceed the cost limit. However, your conditions may be unique. For example, a vessel with external keel cooling may not be able to achieve specified cooling levels required by the kit without extensive modifications to the vessel hull. If you think a kit is not available for your engine 

for either of these reasons, you should contact EPA. 

When must I use a kit if I’m doing a rolling rebuild? 

A rolling rebuild typically refers to the practice of replacing and upgrading parts incrementally 

over many years. If you are doing a rolling rebuild and your schedule includes replacing/requalifying all your cylinder liners over five years or less, you are remanufacturing your engine according to this program. In the case of a rolling rebuild, the clock that determines your deadline for 

complying with the rule starts on the date when the first set of cylinder liners is replaced, after a 

kit is available. This compliance clock stops on the date of replacement of the last set of cylinder liners that completes the remanufacturing, even if this is less than five years from when the 

clock started. If the components of your kit are compatible with your engine’s current configuration, you may install them incrementally at your discretion. However, the latest a certified remanufacture kit must be applied to your engine is when the last set of cylinder liners is replaced, 

as determined from the clock start date described above. 

What are my obligations if a kit is not available today? 

If a certified remanufacture kit is not available for your engine, you must continue to comply 

with the otherwise applicable engine rebuilding requirements in 40 CFR Part 94 when you 

rebuild your Category 1 or Category 2 marine engine. 

Also, before you schedule your next cylinder liner replacements, you should check EPA’s web 

site at www.epa.gov/otaq/certdata.htm to see if a kit has become available for your engine. 



Questions and Answers

I want to certify a marine remanufacture kit. How can I do this? 

Anyone can certify a marine remanufacture kit, by applying to EPA for certification. You must 

submit test results showing that the kit will reduce PM emissions as required by the rule. Your 

application must also show whether owners may obtain and install the remanufacturing kit in 

a timely manner for a total cost that is less than $45,000 per ton of PM reduced. The details 

on submitting an application can be found at 40 CFR Part 1042, Subparts C and I. You should 

contact EPA with any questions on your application. 

Due to similarities between the Marine Remanufacture Program and the Locomotive Engine 

Remanufacture Program, we have a streamlined process to allow locomotive kits to be certified for use with marine engines. You should contact EPA if you think your kit qualifies for this 

process. 

What exemptions apply for special situations? 

Revenue-Based Deferral: 

You do not have to use a certified kit when you remanufacture your engine, if you can show that 

your gross annual sales revenue (including all revenues from any parent company and its subsidiaries) was less than $5 million in 2008 dollars 4

 (footnotes), during the calendar year prior to 

the remanufacture event (or the compliance date in the case of a rolling rebuild). Although you 

do not need to apply to EPA to receive this deferral, you should keep records of your calculations for each year that you qualify. 

State Program Exemption: 

You may qualify for an exemption if you install emission controls before January 1, 2017 on your 

covered marine engine as part of a retrofit program through your state or local government. You 

must apply to EPA for this exemption before you remanufacture your engine. 

Hardship Exemptions: 

There are two ways to qualify for a hardship exemption under this program. You must apply to 

EPA for either of them. 

•	 EPA may approve an exemption if you demonstrate that circumstances out of your 

control prevent you from meeting all the requirements of this rule. You must submit a 

compliance plan, explaining how much more time you need to comply. 

•	 EPA may approve an exemption if you can show that a remanufacture kit is not “available” for your vessel (see “When is a certified remanufacture kit considered available?,” 

above). 



--------------------------------------------------------------------------------

Questions and Answers

Where can I get more information? 

You can review the regulation online by going to the electronic Code of Federal Regulations 

at: http://ecfr.gpoaccess.gov and then browsing for Title 40, Part 1042. Remanufactured engines 

are discussed in Subpart I of the rule, from sections 1042.801 to 1042.850. Section 1042.801 

describes who is subject to this rule, as well as requirements for fuel kits and the state program 

exemption. Section 1042.850 describes the other exemptions. 

You can review the preamble to this rule as well as other related documents at EPA’s Marine 

Diesel web site at www.epa.gov/otaq/marine.htm. 

You can also contact us at: 

U.S. Environmental Protection Agency 


Office of Transportation and Air Quality 


Assessment and Standards Division


2000 Traverwood Dr.


Ann Arbor, MI 48105 


E-mail: asdinfo@epa.gov


(footnote:) 

1

 Depending on engine size, this could be 2008, 2011, 2012, or 2013. Information about the 

standards to which an engine is certified is located on the engine label. For help identifying your 

engine’s tier, contact the engine manufacturer or EPA. 

2

 This is roughly equivalent to 800 horsepower (hp). This information is also on the engine 

label. 

3 This program does not apply to Category 3 marine engines. There is a separate existing program for Category 3 marine diesel engines; you may contact EPA for more information about 

that program. 

4

 Visit www.bls.gov for the Producer Price Index to calculate the equivalent 2008 dollars for 

another year.