How to manage black exhaust smoke

Attention to load will improve power pack performance.

Power packs are the lifeblood of most reefer cargo operations. Keeping them in top shape through regular maintenance is a necessity.
Understanding load and how it affects power pack health is a critical part of this process.

Is your power pack underloaded?

It might seem obvious that overloading a power pack can have negative implications for a generator’s performance. Yet under-loading can be just as serious, if not more problematic to its long term health.

What does it mean to under-load a power pack?

An underloaded power pack is defined when the amount of load (Reefers) is far below the available power (Plugs) that the power pack is equipped to handle.

This situation may be unavoidable from time to time as there may only be limited numbers of refrigerated containers in your yard - as might be the case between shipments. Other times, it is a practice done intentionally under the misconception that this helps prevent the generator from having to work too hard.

The negative effects of under loading (wet-stacking).

Professionally built Power Packs are designed to precise specifications based upon the amount of load (or electricity) they are demanded to produce. Anything short of that, and the generator is not operating to its fullest potential. They will use more fuel, burn oil, and wet stack (produce black smoke) – issues that in time will lead to a shorter equipment life expectancy and sudden failure.

Wet-Stacking Power Pack Reefer Generator
Left: Black residue around the exhaust vent is a sign of an under-loaded power pack. Right: How an efficiently loaded power pack will look.

If you are experiencing black exhaust smoke issues, a rather common occurrence called wet-stacking is likely due to the power pack's lack of load.


To correct this situation, avoid running them on less than the optimal load for long periods of time. We understand that this may not always be practical given the number of reefers available. However, diesel-powered generators perform best when they are fully loaded up with reefer plugs. So be sure to manage them to full capacity periodically or consistently maintain them at an optimal load per generator.

What is the optimal load?

The number of actual reefers needed to obtain optimal load will vary from one size power pack to another. As a general rule of thumb, it is recommended to maintain a minimum of 70% capacity to reach the point at which the generator is working efficiently enough to burn cleanly and avoid maintenance concerns like wet-stacking (Black Exhaust Smoke).

As an example, the optimal load on a 40 plug power pack should be around 28 reefers. This is provided, of course, that the 40 plug power pack is built to proper specification.

* Care should be taken for hot boxes being brought down to temp not to overload the unit. Always follow the manufacturer's recommended operating instructions.


When possible, load up your Power Packs and let them run. Do this, and your black exhaust smoke issues will go away. But if problems persist, it could be signs of a bigger concern. Contact Power Pool Plus for further direction to help resolve.

Have other Power Pack performance questions? Contact us today.

Jose Alberto Castillo Joins Power Pool Plus

Power Pool Plus welcomes LATAM sales manager

Alberto Castillo Joins Power Pool Plus
Container Management LATAM Edition October 2019

Power Pool Plus Welcomes Jose Alberto Castillo Magaña as Sales Manager of LATAM
Alberto provides his experiences in customer support to port equipment sales

(Alpha, New Jersey USA) Power Pool Plus is proud to announce the addition of Alberto Castillo as our Regional Sales Manager of Latin America. Alberto joins Power Pool Plus with past experience in addressing the heavy lifting requirements of both port and construction equipment operators. Mr. Castillo will be responsible for developing new business relationships and promoting our reefer generator products and related services throughout Mexico, Central America, and South America. Mr. Castillo is trained in mechanical engineering and is an accomplished sales professional with experience in solving unique challenges that maximize customer efficiencies.

Ports throughout Latin America are ever expanding their footprint in the perishable goods trade. This new role with Power Pool Plus will be to provide unique power generation solutions for port operators that are actively engaged in the throughput of refrigerated container cargo. Alberto is no stranger to the requirements of port operations. Based out of Mexico City, Mr. Castillo has most recently represented Taylor Machine Works International as the Regional Sales Manager of Mexico and SITSA in Mexico City as Sales Representative for Kalmar equipment and terminal tractors. Both roles addressed the capital equipment needs of port facilities.

According to Adam Hulse, VP Sales, “Having a regional representative in Latin America has been a goal for Power Pool Plus for some time. Alberto’s valued experiences and innate appreciation for meeting customer expectations is a perfect fit to the character of Power Pool Plus that we believe our customers in this region will benefit from. Everyone on our team is very excited to have him on board with us.”

“Power Pool Plus has the right products to address port operators throughout Latin America,” says Mr. Castillo. “I am excited about this opportunity to apply my knowledge and creative imagination in helping our customers with their reefer power needs.”

From spikes in seasonal cargo throughput to the efficient use of power packs to mitigate challenges in dependable ground power, Power Pool Plus is committed to helping port operators throughout Latin America to be successful in managing the ever expanding volumes of refrigerated container cargo. Mr. Castillo’s experiences and professional acumen will be an asset not only to Power Pool Plus, but to the customers that he will effectively serve.

PMAC Silver Sponsor Award 2019

Power Pool Plus receives Silver Sponsor Awared at 2019 PMAC Conference

Power Pool Plus was an honored recipient of the Silver Sponsor Award at this year’s 2019 Annual General Meeting of the Port Management Association of the Caribbean (PMAC), held at the Westin Resort in Fort Lauderdale, Florida from June 26th – 28th, 2019.

The mission of PMAC is "To foster operational growth and financial efficiency, and to enhance the level of service to the mutual benefit of Caribbean Ports and their stakeholders through the sharing of experience, training, information and ideas." This, their 22nd annual event, featured a number of noteable stats; first time held in the USA, highest particiapation at 17 of 18 member ports, and one of the largest attended meetings to date.

Attendees and speakers from around the Caribbean Basin and points around the globe shared insight on the digitalization of the port environment, predictive analysis of port equipment to mitigate machinery downtime, the future of port modernization, and a topic critical to the needs of Caribbean port operators, discussing current regional initiatives in disaster relief and logistics. The latter topic remained of high importance due to the nature of island relief as island ports being the only conduit to receive such aid.

Presenting to the group, Ted Shelson, Marketing Director/Power Pool Plus, provided a general overview to the delegation of our Purpose Built Power Generation Solutions and how they can be uniquely configured to meet the individual needs of every port customer whether for reefer, ground power, or a specialized combination of the two.

Power Pool Plus
Purpose Built Power Generation Solutions
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