25A Boost for Deeply Discharged Batteries
When a battery needs more than routine charging but doesn’t immediately require Engine Start assistance, the 25A Boost mode provides a higher charging rate.
Boost mode is designed to quickly add charge to a deeply discharged compatible 12V battery before attempting to start the vehicle.
This provides three distinct levels of capability:
175A Engine Start – High-current starting assistance
25A Boost – Rapid charging for deeply discharged batteries
6A Charge – Steady routine battery charging
That flexibility makes the CMXCESM274 useful for more than emergency starts. It can move from recovering a discharged battery to routine charging without requiring separate equipment.
6A Standard Battery Charging
For everyday battery charging, the CRAFTSMAN provides a 6A charging mode.
The lower output is appropriate when rapid Boost charging isn’t necessary and provides a more conventional charging rate for compatible 12V batteries.
If a battery repeatedly becomes discharged, however, simply charging it again may only temporarily hide the problem.
Our guide explaining why a car battery keeps dying covers common causes such as battery deterioration, parasitic electrical loads and charging-system problems.
Manual 135-Minute Charging Timer
Unlike fully automatic smart chargers, the CMXCESM274 puts charging control directly in the user’s hands.
Its 135-minute timer lets you determine how long the charger operates based on the battery’s condition and selected charging mode.
Once the selected time expires, the charging cycle shuts off.
This manual approach is particularly appealing to experienced DIYers and technicians who prefer to monitor battery charging rather than relying entirely on automatic charging algorithms.
The tradeoff is responsibility: battery condition and charging progress should be monitored during use.
Old-school control means you get to make the decisions. Unfortunately, that also means the charger has someone to blame.
Analog Ammeter
Charging status is displayed through a traditional analog ammeter.
The gauge provides a straightforward visual indication of charging current without requiring menus, digital displays or mode screens.
For technicians accustomed to traditional garage chargers, an analog meter can make it easy to monitor how the battery responds during the charging cycle.
Changes in charging current can also provide useful information about battery behavior as charging progresses.
Standard, AGM, Gel and Deep-Cycle Battery Support
The CRAFTSMAN CMXCESM274 is compatible with several common 12V battery types, including:
- Standard lead-acid batteries
- AGM batteries
- Gel batteries
- Deep-cycle batteries
This makes the charger useful across a broad range of automotive and recreational equipment.
Always verify battery voltage, chemistry and recommended charging rate before selecting a charging mode.
The CMXCESM274 is specified for compatible 12V batteries and should not be assumed compatible with lithium-ion or LiFePO4 batteries unless explicitly approved by the manufacturer.
Built for Cars, Trucks, SUVs and More
The combination of 6A charging, 25A Boost and 175A starting assistance makes the CMXCESM274 suitable for a variety of vehicle types.
Typical applications include:
- Passenger cars
- Pickup trucks
- SUVs
- Motorcycles
- ATVs
- RVs
- Boats and marine equipment
- Farm and utility equipment with compatible 12V batteries
Its wheeled construction is particularly convenient when working on several vehicles because the charger can be rolled around the garage rather than carried from battery to battery.
Heavy-Duty Steel Construction
The CMXCESM274 is designed more like a traditional shop charger than a compact electronic maintainer.
Heavy-duty features include:
- Rugged steel case
- Heavy-duty battery clamps
- 8-gauge battery cable
- Solid compact wheels
- Retractable handle
- Garage-oriented wheeled design
The retractable handle and compact wheels make the charger easier to move while also allowing the handle to be lowered for more compact storage.
This is the sort of charger intended to live against the garage wall for years rather than disappear into the glove box.
Six-Foot Power and Booster Cables
The charger includes an approximately 6-foot AC power cord and 6-foot booster cables, providing useful working reach around vehicles.
Because the CMXCESM274 requires external AC power, consider outlet location when positioning the charger.
Always route power and charging cables where they won’t be pinched, driven over or exposed to moving engine components.
Battery Charging Can Help Diagnose Starting Problems
A properly charged battery is an important starting point for diagnosing a vehicle that cranks slowly or refuses to start.
If the vehicle produces rapid clicking when you turn the key, insufficient battery voltage is a common possibility.
But charging the battery isn’t proof that the battery caused the original problem.
Corroded terminals, damaged cables and poor grounds can restrict starter current even when the battery itself is adequately charged.
Check Voltage Drop Before Replacing Parts
Starter motors require considerably more current than most other electrical components.
That means a cable or connection can operate headlights and accessories normally while still creating enough resistance to prevent proper starter operation.
Our guide to automotive voltage-drop testing explains how to measure voltage loss through battery cables, starter circuits and ground connections while the circuit is carrying current.
If a fully charged battery still produces slow cranking, voltage-drop testing is one of the most useful next diagnostic steps.
When the Car Has Power but Won’t Start
Seeing dashboard lights doesn’t automatically mean the battery and starting circuit are healthy.
The starter requires dramatically more current than most vehicle accessories.
If the car has electrical power but still won’t start, potential causes can include battery connections, cables, starter components, relays and other starting-system faults.
The CMXCESM274’s 175A Engine Start mode can provide starting assistance, but recurring no-start conditions should still be properly diagnosed.
Charging Problems Can Point to the Alternator
If the battery accepts a charge but becomes discharged again after normal driving, inspect the charging system.
Alternator output, belt condition, battery cables, grounds and associated wiring all influence whether the battery receives adequate charging while the engine runs.
Our guide explaining why the battery warning light comes on covers several common charging-system problems worth checking before replacing another battery.
A 175A starter function can get the engine turning. It cannot convince a failed alternator to start doing its job again.
Manual Charger vs. Automatic Maintainer
The CRAFTSMAN CMXCESM274 is best suited to users who specifically want manual charging control and substantial starting assistance.
A small automatic maintainer may be better for leaving a motorcycle or collector car connected throughout months of storage.
The CRAFTSMAN’s strengths are different:
- Higher-current Boost charging
- 175A starting assistance
- Manual charging-time control
- Analog current monitoring
- Heavy-duty wheeled construction
For garage work involving discharged automotive batteries and larger vehicles, those capabilities make it a much different tool than a compact trickle charger.
Key Features
- CRAFTSMAN model CMXCESM274
- 2-in-1 battery charger and engine starter
- Compatible with 12V batteries
- 175A Engine Start
- 25A Boost charging
- 6A standard charging
- Manual operation
- 135-minute charging timer
- Automatic shutoff when timer expires
- Analog ammeter
- Standard lead-acid battery compatibility
- AGM battery compatibility
- Gel battery compatibility
- Deep-cycle battery compatibility
- Suitable for gasoline and compatible diesel vehicles
- Heavy-duty steel housing
- Heavy-duty clamps
- 8-gauge battery cable
- Retractable handle
- Solid compact wheels
- Approximately 6-foot power cord
- Approximately 6-foot booster cables
- AC-powered operation
Traditional Garage Charger with Serious Starting Power
The CRAFTSMAN CMXCESM274 175A 12V Wheeled Battery Charger and Engine Starter is designed for users who want more control and starting capability than a small automatic maintainer provides.
Its 6A setting handles routine charging, the 25A Boost mode helps replenish deeply discharged batteries more quickly, and the 175A Engine Start function provides substantial starting assistance when a vehicle needs help getting cranked.
The manual 135-minute timer and analog ammeter provide direct control over the charging process, while the steel housing, wheels and retractable handle make the charger well suited to a working garage.
No app. No Bluetooth. No touchscreen asking you to create an account before charging your battery. Sometimes progress means a timer, an analog gauge and 175 amps.
There are no reviews yet.