MTU 12V 4000 M70 Charge-Air Cooler / Aftercooler Part Numbers & Guide
Looking for a charge-air cooler, intercooler or aftercooler for an MTU 12V 4000 M70 marine engine?
You may already have a cooler removed from the engine and need to identify its part number. Or perhaps you're investigating high intake-air temperature, reduced engine performance or a cooling-system problem.
The first thing to know is that MTU 12V 4000 M70 identifies the engine type, but it should not be used by itself to select a replacement charge-air cooler.
Documented charge-air-cooler references associated with the MTU 12V 4000 M70 include:
| EngineComponentPart Number | ||
| MTU 12V 4000 M70 | Charge-Air Cooler / Intercooler | X52611100021/31 |
| MTU 12V 4000 M70 | Charge-Air Cooler / Intercooler | X52611300033/31 |
These references should not automatically be treated as interchangeable.
Before ordering, verify:
Complete engine model + engine serial number + existing cooler part number + cooler position/configuration
Does the MTU 12V 4000 M70 Have an Intercooler?
Yes.
The MTU 12V 4000 M70 marine engine uses charge-air cooling as part of its combustion-air system.
MTU documentation describes the Series 4000 M70 combustion-air system as using an engine-coolant-temperature-controlled intercooler together with turbocharging.
The purpose of the cooler is straightforward:
Turbocharger compresses air → compressed air becomes hotter → intercooler removes heat → cooler charge air enters the engine
This cooling process helps maintain the charge-air conditions required for efficient engine operation.
MTU X52611100021/31 Charge-Air Cooler
One documented charge-air-cooler reference associated with the MTU 12V 4000 M70 is:
X52611100021/31
This component is also described in parts references as an:
Intercooler
or:
Charge-air cooler
If X52611100021/31 appears on your existing cooler or maintenance records, include the complete number when requesting a replacement.
Do not shorten the number unnecessarily.
For accurate identification, provide:
MTU 12V 4000 M70 + engine serial number + X52611100021/31 + photograph of existing cooler
MTU X52611300033/31 Charge-Air Cooler
Another documented charge-air-cooler reference associated with the MTU 12V 4000 M70 is:
X52611300033/31
Parts references also describe this component as an intercooler, including a right-hand intercooler description.
This is exactly why the engine designation alone isn't enough.
An engine may have different cooler positions or configurations, and similar-looking charge-air coolers should not automatically be treated as interchangeable.
If your existing cooler shows:
X52611300033/31
send that complete reference together with the engine serial number.
Are X52611100021/31 and X52611300033/31 the Same?
Do not assume so.
Both references are documented in connection with MTU 12V 4000 M70 charge-air cooling, but that does not mean one can automatically replace the other.
The cooler's:
Position
Connections
Configuration
Engine arrangement
and:
Existing identification
should be checked.
For parts identification, the safest approach is:
Match the existing cooler number first, then verify against the complete engine identification.
Why Is It Called an Intercooler, Charge-Air Cooler or Aftercooler?
Marine engineers, parts suppliers and vessel operators may use several terms when searching for this component.
Common searches include:
MTU 12V 4000 M70 intercooler
MTU 12V4000M70 charge-air cooler
MTU 4000 aftercooler
MTU M70 intercooler
MTU X52611100021/31
MTU X52611300033/31
Technically, charge-air cooler or intercooler is the terminology used in MTU documentation for this system.
However, aftercooler is also commonly used in marine parts searches, so it's useful when identifying what a customer is looking for.
What Does the Charge-Air Cooler Do?
The turbocharger compresses the intake air before it reaches the cylinders.
Compression increases the temperature of that air.
The intercooler removes part of this heat before the charge air reaches the engine.
A simplified airflow path is:
Air filter → turbocharger → charge-air cooler / intercooler → intake system → cylinders
The exact configuration depends on the engine installation.
Efficient charge-air cooling therefore forms an important part of the engine's overall air and cooling systems.
Can a Dirty Charge-Air Cooler Cause Power Problems?
A restricted or contaminated charge-air system can contribute to poor engine performance.
But reduced power should not automatically be blamed on the cooler.
Other areas may need to be investigated, including:
- Air filters
- Turbochargers
- Charge-air piping
- Hose and connection condition
- Air leaks
- Exhaust restriction
- Fuel supply
- Injectors
- Engine sensors and controls
- Vessel loading
A charge-air-cooler problem is therefore one possible cause within a larger system.
What Are Signs of an MTU 12V 4000 M70 Charge-Air Cooler Problem?
Depending on the failure or contamination involved, possible warning signs can include:
Higher charge-air temperatures
Reduced engine performance
Cooling-fluid leakage
Visible corrosion
Contamination
Abnormal temperature differences
Air-system leakage
Reduced cooling efficiency
However, these symptoms are not enough by themselves to prove that the cooler needs replacement.
The complete charge-air and cooling systems should be inspected.
Can I Clean an MTU 4000 Charge-Air Cooler Instead of Replacing It?
That depends on its condition.
A cooler affected mainly by serviceable contamination may be a candidate for inspection and cleaning using an appropriate approved procedure.
Replacement may become necessary when there is significant:
Core damage
Corrosion
Leakage
Connection damage
Structural deterioration
or another defect that prevents reliable continued service.
Don't decide from external appearance alone.
Should I Pressure-Test the Cooler?
When leakage or internal integrity is suspected, appropriate inspection and testing can help determine the cooler's condition.
The procedure and permissible test limits should follow the applicable MTU service information for the exact component.
Avoid applying an arbitrary pressure simply because another marine cooler was tested at that pressure.
Different cooler designs can have different limits.
Why Does the Engine Serial Number Matter?
Because MTU Series 4000 covers many different engine models and configurations.
Even 12V 4000 M70 should not be treated as enough information to select every component.
Compare:
“Need MTU 4000 aftercooler.”
with:
Engine: MTU 12V 4000 M70
Component: Charge-air cooler / intercooler
Existing P/N: X52611100021/31
Engine serial number: provided
Position: provided
Quantity: 1
The second request provides far stronger information for parts identification.
What Information Should I Send When Ordering?
For an MTU 12V 4000 M70 charge-air cooler, provide:
Complete engine designation
Engine serial number
Existing charge-air-cooler part number
Cooler position if known
Quantity required
Vessel/application
If possible, also provide:
Engine data-plate photograph
Existing cooler photograph
Close-up photograph of the cooler identification
This can help distinguish between similar components before ordering.
Need an MTU 12V 4000 M70 Charge-Air Cooler?
Alfa Marine Spare Parts supplies and sources MTU Series 4000 marine engine components for yacht, commercial marine and other vessel applications.
Requirements can include:
- Charge-air coolers / intercoolers
- Aftercoolers
- Turbochargers
- Seawater pumps
- Coolant pumps
- Heat exchangers
- Injectors
- Fuel-system components
- Gaskets and seals
- Sensors and controls
- Other MTU Series 4000 marine engine parts
Already have:
X52611100021/31
or:
X52611300033/31?
Send the complete part number together with your engine serial number.
Request Your MTU Series 4000 Parts Quote
📧 request@alfamarinespareparts.com
➡️ Request A Quote | Alfa Marine Spare Parts
Not sure which cooler you have?
Send us photographs of the engine data plate + existing cooler + cooler identification.
Frequently Asked Questions
Does the MTU 12V 4000 M70 have an intercooler?
Yes. The MTU 12V 4000 M70 marine combustion-air system uses charge-air cooling. MTU describes an engine-coolant-temperature-controlled intercooler in its Series 4000 M70 marine specification.
What is the MTU 12V 4000 M70 charge-air cooler part number?
Documented references associated with the MTU 12V 4000 M70 include:
X52611100021/31
and:
X52611300033/31
The exact requirement should be verified against the engine serial number and existing cooler.
Is X52611100021/31 an MTU intercooler?
Yes. X52611100021/31 is documented as an MTU intercooler / charge-air-cooler reference and is listed for the 12V 4000 M70.
Is X52611300033/31 an MTU intercooler?
Yes. X52611300033/31 is documented as an MTU intercooler / charge-air-cooler reference associated with the 12V 4000 M70.
Are X52611100021/31 and X52611300033/31 interchangeable?
Do not assume they are interchangeable.
Verify the existing cooler identification, position/configuration and complete engine information before selecting a replacement.
Is an intercooler the same as an aftercooler?
Terminology varies in the marine industry. MTU documentation uses intercooler, while charge-air cooler accurately describes the component's function. Buyers may also search for it as an aftercooler.
Can a bad intercooler cause an MTU 12V 4000 M70 to lose power?
A charge-air-cooling problem can contribute to poor engine performance, but it is not the only possible cause.
Turbocharger condition, intake restriction, charge-air leakage, fuel supply, exhaust restriction, engine controls and vessel loading may also need investigation.
What information do I need when ordering an MTU 4000 intercooler?
Provide:
Complete engine model + engine serial number + existing cooler part number + cooler position/configuration + quantity required
For a quotation: