Isuzu 3LA, Manual

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VIII. Isuzu Technology: L-Series Direct Injection
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L-Series Diesel 48
Re-engineering equipment for a new engine model is typically an expensive proposition and stepping up to EPA's Tier
2 regulations in 2004 for off-highway engines in the 25 to 100 hp range will mean just that, but not if the envelope of
the replacement engine is identical with the present engine. Current and prospective users of Isuzu's L-Series engines
will be pleased to learn that the new direct-injection (DI) versions have the same physical footprint as the current IDI
models.
The industrial engines are developed from the technology of well-proven automotive engines. It is certainly the
automotive sector that represents the leading edge in gaseous emissions, but that is also true of customer expectations
with respect to noise, vibration and ease of use. Isuzu produces more than 800,000 diesel engines per year and plans to
produce 1.8 million by 2005.
The L-Series diesels will still be in the picture at that time and that was always the plan from the time they were
introduced by American Isuzu to the U.S. market back in 1993, replacing the well-known K-Series. The three cylinder
L-Series engines were joined by four cylinder versions in 1995. These engines were conceived to be among the
quietest, most compact, lightweight, water-cooled engines in their class and the plan was that this basic platform would
meet CARB, EPA and other applicable emission standards well into the future.
If one looks at the global automotive picture, it is estimated that fully 90 percent of the vehicular diesel engines will be
direct injected after 2000 and the percentage would be even higher were it not for Third World production. The main
motivations are the reduction of CO, and particulate matter emissions and the improvement of fuel economy.
So this is the battleground and direct injection appears to be the weapon of choice. And from this massive automotive
capital base flows the technology base that will then be applied to other engine applications. Virtually all automotive
diesel engines above 3.5 L displacement already use DI technology and many smaller automotive engines are also DI.
Many of Isuzu's engines were developed for automotive as well as industrial use. Included would be the J-Series and
the B-Series in the under 100 hp range. The L-Series, however, was developed strictly for industrial use, yet it too
makes use of the tools of automotive engine design.
With the new DI three cylinder model 3LD2 displacing 1499 cc and the four cylinder 4LE2 displacing 2179 cc, the L-
Series is the smallest series that Isuzu manufactures today. The 3LD2 has a bore and stroke of 83.1 x 92 mm and a
maximum output of 34.8 hp at 3000 rpm, with peak torque of 73.5 lb.ft. at 1800 rpm. The 4LE2 has a bore and stroke
of 85 x 96 mm and a maximum output of 54.4 hp at 3000 rpm, with peak torque of 113.4 lb.ft. at 1800 rpm. All ratings
are SAE J1995 gross hp. Dry weight of the 3LD2 and 4LE2 is given at 290 and 396 lb. respectively.