Avoid Wet Stacking in Your Diesel Generator
The Importance of Load Bank Testing Your Generator
Your diesel generator provides reliable backup power, but it isn’t immune to issues. One common problem, especially for lightly loaded generators, is wet stacking. Left unaddressed, wet stacking can lead to reduced performance, costly repairs, or even a full generator replacement.
Fortunately, there’s a solution: load bank testing. Generator Services, Inc. offers professional load bank testing services for customers throughout South Carolina to keep your generator operating efficiently and avoid preventable damage.
What Is Wet Stacking in Diesel Generators?
Wet stacking is a common issue in diesel generators that occurs when the generator isn’t working hard enough — or, as we say in the industry, “running on too light a load.” Generators are designed to support a certain load, and when a diesel generator consistently runs at less than 30-40% of its capacity (for example, powering only a few lights or small appliances), the engine just doesn’t get hot enough to fully burn the diesel fuel being injected into it.
As a result, unburnt fuel begins to build up in the exhaust system, which consists of “stacks” (a term for the exhaust pipes where fumes exit the generator). This accumulation is what gives the problem its name — wet stacking — because the unburnt fuel creates a “wet” residue inside the exhaust stacks. Over time, this residue can harden into carbon deposits, clogging vital components and leading to reduced performance, higher fuel consumption, and eventual breakdowns and repairs.
Be on the lookout for these signs of wet stacking:
- Black exhaust smoke
- Hard carbon deposits or soot forming
- Thick, unburnt fuel leaking from the exhaust system
If you notice these signs, your generator may already be experiencing the effects of wet stacking. Acting quickly can prevent further damage.
How Load Bank Testing Can Prevent Wet Stacking
Since the primary cause of wet stacking is operating a generator on too light a load, load bank testing addresses this by running your generator at a controlled, higher load — typically 75-100% of its capacity — for several hours. This process burns off any unburnt fuel in the exhaust system, clearing carbon and soot buildup to restore the generator’s performance and efficiency.
By regularly performing load bank testing, you can protect your diesel generator from damage, prolong its lifespan, and make sure that it’s ready when you need it during power outages.
When Load Bank Testing Isn’t Enough
In severe cases of wet stacking, load bank testing alone may not be sufficient to reverse the damage. Extensive buildup or prolonged neglect can require an engine overhaul or even a complete replacement. The best way to prevent this is by addressing wet stacking early through routine maintenance and testing.
Contact Generator Services, Inc. for Load Bank Testing & Generator Repair in South Carolina
If your diesel generator is experiencing issues such as wet stacking or engine blow-by, contact Generator Services, Inc. for expert generator maintenance, repair, and replacement. We’ve been keeping South Carolina’s generators running for over 30 years. Our licensed and insured technicians are experienced in handling all types of generators, from residential standby units to large industrial systems.
With upfront pricing, 24/7 emergency services, and financing options, we ensure reliable power when you need it most. Whether you’re in Columbia or anywhere in the Midlands region, GSI is your partner in keeping your generator running at peak performance.
Contact our team today to schedule professional load bank testing, repair, or replacement services throughout Columbia and the Midlands.
