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    • Caterpillar/Towmotor GP25NM Parts

    Picture for manufacturer Caterpillar/Towmotor

    Aftermarket and replacement parts for the Caterpillar/Towmotor GP25NM, built to original equipment specifications. Browse compatible components to find the right part for your equipment.

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    We stock aftermarket Caterpillar/Towmotor GP25NM components manufactured to OEM-spec dimensions, so downtime stays short and you skip the OEM markup. Not sure which part fits your GP25NM? Contact us and we'll verify it before you order.

    Guides for this model

    Nissan K21 and K25 Engines Explained

    The K21 and K25 are four-cylinder industrial engines sharing an 89 mm bore and differing in stroke, at 2,065 cc and 2,488 cc. Both use an overhead-valve pushrod valvetrain with a rocker shaft and screw adjusters, a bathtub combustion chamber, a timing chain, five main bearings and a chain-driven side power take-off. Both run gasoline or LPG.

    Nissan K21 and K25 Maintenance and Troubleshooting

    Routine service on a K21 or K25 covers valve clearance set hot at 0.38 mm on every valve, a cold retighten of the head bolts and manifold nuts, belt deflection, oil and filter, plugs, air and fuel filters and coolant. Most running complaints trace back to compression, ignition or fuel, and a compression test separates them quickly.