[Code of Federal Regulations]
[Title 40, Volume 31]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR1068.120]

[Page 826-827]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 1068_GENERAL COMPLIANCE PROVISIONS FOR 
NONROAD PROGRAMS--Table of Contents
 
          Subpart B_Prohibited Actions and Related Requirements
 
Sec.  1068.120  What requirements must I follow to rebuild engines?

    (a) This section describes the steps to take when rebuilding engines 
to avoid violating the tampering prohibition in Sec.  1068.101(b)(1). 
These requirements apply to anyone rebuilding an engine subject to this 
part, but the recordkeeping requirements in paragraphs (j) and (k) of 
this section apply only to businesses.
    (b) The term ``rebuilding'' refers to a rebuild of an engine or 
engine system, including a major overhaul in which you replace the 
engine's pistons or power assemblies or make other changes that 
significantly increase the service life of the engine. It also includes 
replacing or rebuilding an engine's turbocharger or aftercooler or the 
engine's systems for fuel metering or electronic control so that it 
significantly increases the service life of the engine. For these 
provisions, rebuilding may or may not involve removing the engine from 
the equipment. Rebuilding does not normally include the following:
    (1) Scheduled emission-related maintenance that the standard-setting 
part allows during the useful life period (such as replacing fuel 
injectors).
    (2) Unscheduled maintenance that occurs commonly within the useful 
life period. For example, replacing a water pump is not rebuilding an 
engine.
    (c) For maintenance or service that is not rebuilding, you may not 
make changes that might increase emissions

[[Page 827]]

of any pollutant, but you do not need to keep any records.
    (d) If you rebuild an engine or engine system, you must have a 
reasonable technical basis for knowing that the rebuilt engine's 
emission-control system performs as well as, or better than, it performs 
in its certified configuration. Identify the model year of the resulting 
engine configuration. You have a reasonable basis if you meet two main 
conditions:
    (1) Install parts--new, used, or rebuilt--so a person familiar with 
engine design and function would reasonably believe that the engine with 
those parts will control emissions of all pollutants at least to the 
same degree as with the original parts. For example, it would be 
reasonable to believe that parts performing the same function as the 
original parts (and to the same degree) would control emissions to the 
same degree as the original parts.
    (2) Adjust parameters or change design elements only according to 
the original engine manufacturer's instructions. Or, if you differ from 
these instructions, you must have data or some other technical basis to 
show you should not expect in-use emissions to increase.
    (e) If the rebuilt engine remains installed or is reinstalled in the 
same piece of equipment, you must rebuild it to the original 
configuration or another certified configuration of the same or later 
model year.
    (f) If the rebuilt engine replaces another certified engine in a 
piece of equipment, you must rebuild it to a certified configuration of 
the same model year as, or a later model year than, the engine you are 
replacing.
    (g) Do not erase or reset emission-related codes or signals from 
onboard monitoring systems without diagnosing and responding 
appropriately to any diagnostic codes. This requirement applies 
regardless of the manufacturer's reason for installing the monitoring 
system and regardless of its form or interface. Clear any codes from 
diagnostic systems when you return the rebuilt engine to service. Do not 
disable a diagnostic signal without addressing its cause.
    (h) When you rebuild an engine, check, clean, adjust, repair, or 
replace all emission-related components (listed in Appendix I of this 
part) as needed according to the original manufacturer's recommended 
practice. In particular, replace oxygen sensors, replace the catalyst if 
there is evidence of malfunction, clean gaseous fuel system components, 
and replace fuel injectors (if applicable), unless you have a reasonable 
technical basis for believing any of these components do not need 
replacement.
    (i) If you are installing an engine that someone else has rebuilt, 
check all emission-related components listed in Appendix I of this part 
as needed according to the original manufacturer's recommended practice.
    (j) Keep at least the following records:
    (1) Identify the hours of operation (or mileage, as appropriate) at 
time of rebuild.
    (2) Identify the work done on the engine or any emission-related 
control components, including a listing of parts and components you 
used.
    (3) Describe any engine parameter adjustments.
    (4) Identify any emission-related codes or signals you responded to 
and reset.
    (k) You must show us or send us your records if we ask for them. 
Keep records for at least two years after rebuilding an engine. Keep 
them in any format that allows us to readily review them.
    (1) You do not need to keep information that is not reasonably 
available through normal business practices. We do not expect you to 
have information that you cannot reasonably access.
    (2) You do not need to keep records of what other companies do.
    (3) You may keep records based on engine families rather than 
individual engines if that is the way you normally do business.

[67 FR 68347, Nov. 8, 2002, as amended at 69 FR 39266, June 29, 2004]