Engine - Performance Improvements
83toyota3REFERENCE: ENGINE
NUMBER: 005
DATE: 2-25-83
MODEL: LN44
TITLE L DIESEL ENGINE PERFORMANCE IMPROVEMENTS
To improve performance the following modifications have been made on the L engine.
1. Piston
The top ring carrier and land is reinforced with ceramic fiber.
Due to this new technology, the wear resistance of the top ring and ring groove has been increased greatly.
2. Valve Rocker Arm, Camshaft and Camshaft Bearing Cap
To increase wear resistance, a new roller-type valve rocker arm has been adopted. Along with this, the camshaft profile has been modified.
Consequently, the camshaft bearing cap has also been modified as shown below.
3. Fuel Injection Pump
3-1. A new ACTA (Altitude Compensating Timing Advancer) has been adopted.
This ACTA controls the fuel injection timing according to atmospheric pressure, and provides excellent driveability at all altitudes. Because of ACTA, it is no longer necessary to change the initial injection timing for high altitude use. *Initial Injection Timing is 1.12 mm for all engines after L-0603464 (JT4LN44**1111497).
3-2. Load Sensing Timer
To meet NOX emission standards, a load sensing timer has been added.
4. Injection Nozzle
The opening pressure has been changed from 130 kg/sq. cm. (1848 psi) to 160 kg/sq. cm. (2275 psi). The fuel flow characteristics have also been changed.
5. Preheating Timer
To reduce smoke emission when engine is cold, the after-glow time has been extended.
Coolant Temperature (~ C) -20 0 + 20 +40 +70
Prev. After-Glow Time (sec) 132 80 44 25 11
New After-Glow Time (sec) 240 180 103 53 15
PRODUCTION EFFECTIVE:
From Production Date
L-0603465 October 1982
From Frame Number
JT4LN44**D1111498 October 1982
PART NUMBER INFORMATION:
Previous New
Part Number Part Number Part Name
13101-54021 13101-54040 Piston sub-assy, w/pin (STD)
13801-54012 13801-54020 Arm sub-assy, valve rocker No. 1
13802-54011 13802-54020 Arm sub-assy, valve rocker No. 2
13501-54030 13501-54020 Camshaft sub-assy
11101-54024 11101-54040 Head sub-assy, cylinder
22100-54250 22100-54290 Pump assy, injection (w/tachometer)
22100-54300 Pump assy, injection (w/o tachometer)
23600-54030 23600-59025 Holder and nozzle set, nozzle
28521-54131 28521-54200 Timer, preheating
NOTE: These parts are interchangeable as a set.