Caterpillar G3516C
1,555 ekW continuous, and the one Caterpillar gas model with enough resale data to price, at 273.31 to 599.93 dollars per kW
Caterpillar G3516C is one of 23 gas engines tracked in the SecondWatt catalogue, each with specifications, lead times and indicative secondary-market pricing.
Caterpillar G3516C: 1,555 ekW continuous, with verified resale pricing of 273 to 600 dollars per kW. Specs, lead times and inspection points.
The Cat G3516C is the C generation of the 3500-block G3516, published by Caterpillar at 1,555 ekW continuous with rating classes of 801 to 1,250, 1,251 to 1,500 and 1,501 to 2,000 kW. It is the model with the deepest priced inventory in the North American Caterpillar gas resale channel, and the one current Caterpillar gas model with enough public listings to support a published price range. One designation trap needs care. Caterpillar's current G3516C product page describes a low-energy coal mine methane set at 37.70 percent maximum electrical efficiency on 50 Hz. The G3516C units actually transacting in North America are natural gas machines at 60 Hz. The designation covers both, so never read the 37.70 percent coal mine methane figure as the natural gas efficiency. Caterpillar publishes no C-generation block geometry. The bore, stroke and displacement quoted here come from the G3516 TA engine specification and are labelled with that provenance: a V-16 four-stroke of 170 mm bore, 190 mm stroke and 69 L, turbocharged with two-stage aftercooling. Those are the same three figures Caterpillar publishes for the 3516B diesel.
Why it matters
This is the only current Caterpillar gas model where the resale market is deep enough to publish a number. Everything else in the Caterpillar gas range is a quote market, so the G3516C is the reference point a buyer can actually anchor a negotiation against.
Who buys it
Secondary-market buyers who want megawatt-class gas capacity now rather than on a new-build lead time. Landfill gas, coal mine methane and low-energy-gas operators, which is the duty Caterpillar markets the current C variant into. Data center and industrial developers bridging a gap while new units are on order, often through the containerised XQ1475G package.
Role in the data center
Bridging and interim behind-the-meter capacity at roughly 1.5 MW per set, bought used or new-surplus when a new-build lead time will not meet a date. The containerised XQ1475G package is the version most likely to suit a data center site, because it arrives as a deployable block rather than a skid needing a building. For permanent prime power a buyer should cross-shop the current G3516 FAST RESPONSE and G3516H, which Caterpillar still sells new and supports with a complete published specification.
Key specifications
| Continuous rating | 1,555 ekW |
|---|---|
| Maximum electrical efficiency, coal mine methane variant | 37.70 percent |
| Fuel on the current Caterpillar page | Coal mine methane fuel type |
| Published rating classes | 801 to 1,250; 1,251 to 1,500; 1,501 to 2,000 kW |
| Cylinder configuration (G3516 TA sheet) | V-16, four-stroke layout |
| Bore (G3516 TA sheet) | 170 mm (6.7 in) |
| Stroke (G3516 TA sheet) | 190 mm (7.5 in) |
| Displacement (G3516 TA sheet) | 69 L (4,211 cu in) |
| Aspiration (G3516 TA sheet) | Turbocharged, two-stage aftercooled aspiration |
| Comparison: Cat 3516B diesel bore and stroke | 170 x 190 mm, same block geometry |
| New-surplus observation | 1,555 kW prime, 346/600 V, 60 Hz, 2014, 0 hours, 425,000 USD priced observation |
| Subpart JJJJ NOx ceiling for this class | 1.0 g/HP-hr or 82 ppmvd at 15 percent O2 regulatory limit |
Technical summary
Continuous rating: 1,555 ekW (Caterpillar product page, coal mine methane variant). Published rating classes: 801 to 1,250 kW, 1,251 to 1,500 kW, 1,501 to 2,000 kW. Maximum electrical efficiency: 37.70 percent on the coal mine methane variant at 50 Hz. Fuel on the current Caterpillar page: coal mine methane; resale units are natural gas at 60 Hz. Engine block, from the G3516 TA sheet: V-16 four-stroke, bore 170 mm, stroke 190 mm, 69 L. Aspiration, from the G3516 TA sheet: turbocharged, two-stage aftercooled. Containerised variant: XQ1475G, 1,475 kW, identified by Surplus Record as carrying a G3516C engine. Observed resale ratings: 1,475 kW, 1,500 kW and 1,555 kW at 277/480 V and 346/600 V, 60 Hz.
Major variations
The XQ1475G is the containerised package built on a G3516C engine at 1,475 kW, identified as such by Surplus Record. Sister XQ designations XQ1250G and XQ1900 also circulate in the North American used market. The wider G3516 designation spans plain, B, C, K, H and LE generations. The H generation is a different 215 mm-stroke block and is not interchangeable with this one despite the shared root number. MWM is Caterpillar. Caterpillar Energy Solutions GmbH of Mannheim was renamed from MWM GmbH on 1 November 2013 and the MWM brand continues. The Cat CG-series is the MWM TCG engine under a Cat badge, and the published numbers prove it rather than merely suggesting it. The CG260 and the MWM TCG 2032 both publish 260/320 mm bore and stroke and match on output and efficiency to the decimal, at 3,333, 4,300 and 4,500 kWe and 43.9, 44.1 and 44.6 percent electrical.
Configurations and options
Caterpillar's current page positions the G3516C as a low-energy gas machine for coal mine methane, at 37.70 percent maximum electrical efficiency on 50 Hz. Landfill gas variants of the same generation also circulate. The North American resale fleet is natural gas at 60 Hz, at 277/480 V and 346/600 V. Confirm which configuration a listing describes, because the fuel train, derate and efficiency all differ between pipeline gas and waste gas.
Compatibility and dependencies
The G3516 and the 3516B diesel share the Cat 3500 block. Caterpillar publishes 170 mm bore, 190 mm stroke, 69 L and a V16 layout on both. They are not the same engine: the diesel is a 14.0:1 compression-ignition unit with electronic unit injection, while the gas set is spark-ignited with a gas fuel train and a different emissions package. What carries across is parts overlap, shared service tooling and a Cat technician base already fluent in the 3500 platform. What does not carry across is ratings, duty, overhaul intervals or the emissions rule. Diesel sets fall under 40 CFR 60 Subpart IIII for compression ignition; this one falls under Subpart JJJJ for spark ignition.
Pricing and availability
Published price range: $273 to $600 per kW. Comparable secondary-market band: 125–627.03 $ per kW. Trend: rising Condition here is dominated by hours to overhaul rather than by model year, and the resale boards rarely publish hours at all. That is the main reason the observed spread runs from 273.31 to 599.93 dollars per kW on three units of similar rating. A structural quirk sits underneath the wider family data. Used G3516 pricing has a median of 418.36 dollars per kW while used G3520 pricing sits at 208.84, even though the G3520 is the larger machine. Both medians rest on high-hour units and the listings do not publish hours consistently enough to explain it, so treat the observation as real and the explanation as unproven. A buyer shopping on dollars per kW alone will misread this market. Lead time, new: The current Caterpillar G3516C page describes a coal mine methane variant and publishes no lead time. Global Power Supply publishes no natural gas genset lead time above 500 kW for 2026, which is the entire range this model occupies. New-surplus stock is the practical route at this rating.. Lead time, used or refurbished: Immediate where inventory exists.. Warranty, used: Individual resellers advertise their own coverage, which is a reseller claim rather than a Caterpillar-published warranty..
Lifecycle and maintenance
Caterpillar publishes no MTBF and no overhaul interval in hours for the G3516C. The only Cat-published maintenance interval in the gas line is up to 4,000 operating hours on the CG170 series. This model carries the best field evidence in the Caterpillar gas range instead. A 2010 unit and a 2014 zero-hour new-surplus unit both transacted in 2026, and the wider Caterpillar gas fleet changes hands at 37,000 to 62,000 hours while still holding value. MWM publishes 48,000 to 80,000 hours to major overhaul on the CG-series engines Caterpillar also owns, which are different engines under a different brand, so those hours are context rather than this model's figure.
Thermal and emissions profile
Caterpillar publishes no NOx, carbon monoxide or formaldehyde figure for the G3516C. The governing rule is 40 CFR 60 Subpart JJJJ, which caps lean-burn natural gas non-emergency spark-ignition engines at or above 500 HP at 1.0 g/HP-hr NOx, or 82 ppmvd at 15 percent O2. Caterpillar publishes 0.50 and 1.00 g/bhp-hr tunes on other models in its range, and the 1.00 figure sits exactly on that ceiling with no margin. Waste-gas duty adds a second layer, because landfill and coal mine methane streams carry contaminants that federal NOx limits do not address. Selective catalytic reduction is a capital line item where a local permit rather than the federal rule governs.
Common failure points
- Detonation from low methane number gas — Knock under load, rising exhaust temperature, controller retarding timing
- Spark plugs and ignition coils — Misfire, rough running, rising carbon monoxide, output derate
- Siloxane and contaminant fouling on waste gas — Deposits on valves, pistons and heads, accelerating wear on landfill or digester gas
- Exhaust valve and seat recession — Compression falling on one cylinder, exhaust spread widening, hard starting
- Emissions drift past Subpart JJJJ — Annual stack test returns NOx above 1.0 g/HP-hr or 82 ppmvd at 15 percent O2
- Turbocharger bearing failure — Oil in the charge air, surge, sudden loss of boost and output
- Controls obsolescence — EMCP2+ era panel with no path to plant-level dispatch or modern supervisory control
Inspection checklist
Hours since major overhaul: a 40,000-hour engine near a major prices well below a fresher unit. Hours since top-end: sibling CG-series engines call head work at 16,000 to 40,000 hours. Fuel the unit was actually configured for: coal mine methane, landfill gas and pipeline gas differ. Nameplate duty: resale listings mix prime and continuous; a 1,555 kW prime rating is not continuous. Frequency and voltage: observed units run 277/480 V and 346/600 V at 60 Hz, plus 400 V exports. Stroke on the data plate: 190 mm confirms the 3500 block, not the 215 mm H-series. Confirm package type: an XQ1475G is a containerised 1,475 kW package on a G3516C engine. Year against price: observed units span 2010 to 2014 at 273.31 to 599.93 dollars per kW. NOx tune and certification paperwork: no figure is published for the natural gas variant.
Procurement channels
New units go through Cat dealers and Cat dealer pages price as Request a Quote. Named dealers holding gas stock include Quinn, Hawthorne, Empire, Western States, Cleveland Brothers, Carter, Stowers, Foley, Holt, Milton, Mustang, Ring Power, Toromont, Wheeler and Boyd CAT. The used channel is quote-driven and deep in Texas and western Canada. DEPCO Power Systems publishes more numbers than anyone else; Industrial Motor Power, Power Generation Enterprises, McKain, Powersafe, Collicutt, Lenmark, NineX, Aaron Equipment and Worldwide Power Products carry inventory but mostly withhold price. Price opacity is the defining feature here.
Regional notes
The observed North American fleet is 60 Hz at 277/480 V and 346/600 V, concentrated in Texas and western Canada. The resale channel also carries 400 V and 3,300 V export machines that are not North American spec, so confirm the nameplate. Caterpillar's own claim for the Cat dealer network is 24/7 service, 99 percent parts availability and a 24-hour response guarantee. That is a Caterpillar claim rather than a measured figure. It is still the commercial argument that matters most in this category, because every large competitor is European or thinner on the ground in North America.