Stuffing a Yanmar Diesel Boat Engine in an 80-Series Land Cruiser Doubles the HP

If you’re building a fast car, chances are your engine swap of choice will come from another car. But if you’re building a tough truck for work or off-roading, the wider vehicular world offers a lot of options. There are plenty of stout diesel engines designed for construction equipment or marine applications that will fit under the hood of a pickup truck or SUV and, as this build demonstrates, improve performance.

The 80-Series Toyota Land Cruiser has many fine qualities, but speed isn’t one of them—especially if you’re talking about one of the factory diesels offered outside the U.S. The wrench behind the Rare Vehicles in Action YouTube Channel found a non-automotive upgrade that makes this Toyota, if not genuinely fast, at least less slow. It’s a Yanmar marine engine, albeit one closely related to one offered in the Land Cruiser from the factory.

Yanmar is a Japanese heavy-equipment company specializing in diesel engines, as well as construction equipment. And it manufactures an engine called the 6LP, which is essentially a marine version of the 1HD-FT turbodiesel 4.2-liter inline-six that was briefly offered in the 80-Series Land Cruiser. Repurposing automotive engines for marine applications isn’t unusual; even Lamborghini did it at one time.

This Land Cruiser already had a turbodiesel 4.2-liter inline-six when it left the factory, but the OEM engine had 12 valves while this one has 24. And that helps it produce 320 horsepower, or about twice the output of the stock 12-valve engine. It lowers the zero-to-60 mph time from 16 seconds to 8.8 seconds, and that’s with the stock air intake, which is known to restrict power in these engines, according to the builder.

Toyota Landcruiser 80 Series With Yanmar Marine Engine

While this engine was originally designed for the 80-Series, some modifications were needed to make its modern-day marine descendant work. The seawater pump used for cooling in boats was removed, and a stock Toyota cooling system was plumbed in. The Yanmar oil sump and pickup were replaced with Toyota equivalents for clearance, and the same was done with the injector pump because the Yanmar version doesn’t have a threaded boss for connecting a tach.

The marine engine is connected to a Toyota H152 gearbox, a higher-ratio version of the five-speed manual transmission this Land Cruiser came with from the factory. That helps the engine maintain 60 mph at just 1,600 rpm. The rest of the car also received a thorough going-over, including a rebuilt front axle, repairs to address corrosion and electrical issues, and a new exhaust system. It reportedly covered 200,000 miles under the care of its original owner, and looks ready to cover at least 200,000 more.