| CYLINDER BORING CAUTION |
Cylinder Boring Caution For
1986-99 Toyota 1.5, 2.0 & 2.2L 5E, 3S & 5S Engines
The AERA Technical Committee offers the following information regarding a cylinder boring caution for 1986-99 Toyota 1.5, 2.0 & 2.2L 5E, 3S & 5S engines. AERA originally published information regarding only the 1.5L engine. This publication includes additional engines with a similar concern. This caution has been reported on engines that have been bored to a .040 (1.000 mm) oversize diameter.
Apparently, depending on the amount of overbore the cylinder wall thickness may become insufficient to support compression. Reports of compression in the cooling system have resulted when the bore diameter has been increased by as little as .040 (1.000 mm) oversize.
These blocks have three angular coolant passages between the cylinders as shown below in Figure 1. The passages are drilled at approximately a 45° angle from the engine right side to the engine left side. These passages allow coolant flow between the cylinders and connect the right to left side water jackets.
The shadow of the drilled passage can be seen in Figure 2 as a dark shadow on a failed block that had been bored and honed .040 and placed back in service. Combustion pressure within the cylinder after start-up created the through hole into the water jacket, resulting in combustion in the cooling system. Engine overheating will result when this condition exists. To repair this condition, AERA members report installing cylinder sleeves and then boring back to a standard bore diameter for all cylinders.
The AERA Technical Committe |
| PISTON & ROD ASSEMBLY & ROD BOLT REUSE |
Piston & Rod Assembly & Rod Bolt Reuse for
1989-99 Toyota 1.6 & 1.8L 4A-FE & 7A-FE Engines
The AERA Technical Committee offers the following information on piston and rod assembly and rod bolt reuse for 1989-99 Toyota 1.6 & 1.8L 4A-FE & 7A-FE engines. This information should be used to correctly assemble the pistons to connecting rods and determine whether a connecting rod bolt should be considered for reuse.
Rod bolts considered for reuse should be free of nicks and burrs and allow easily threading the bolt or nut with one's fingers. To further consider the rod bolts for a 1.6L engine, measure the bolt diameter with a caliper at .590 (14.986 mm) from the bottom of the bolt. If the diameter measured at that location is .3386 (8.6000 mm) or greater the bolt may be reused.
To further consider the rod bolts for a 1.8L engine, measure the bolt diameter with a caliper at .787 (20.000 mm) down from the bottom of the connecting rod bolt head. If the diameter measured at that location is .270 (7.000 mm) or greater the bolt may be reused
To assemble the connecting rods for either engine to the pistons, align the protrusion or front mark on the rod with the front mark located on the piston as shown in the illustrations below.
The AERA Technical Committee |
| CONNECTING ROD NUT TIGHTENING CAUTION |
Connecting Rod Nut Tightening Caution On
Toyota 2.5 & 3.0L Engines
AERA machine shops should be particularly cautious when tightening the connecting rod nuts on Toyota 2.5 & 3.0L V-6 engines used in the 4 Runner and Pickup.
The connecting rod nuts for these engines use a combination torque, then turn method to achieve the proper clamping load. First the nut is torqued to 18 lbs.ft., then turned an additional 90°. It is possible for the rod bolt to slightly turn inside the connecting rod during this process, causing the final torque to be below specifications. The nut must be turned 90° relative to the bolt, not the connecting rod.
During assembly, instead of marking the nut and the connecting rod with a paint stick, mark the nut and the bolt to ensure that the proper final torque is achieved.
The AERA Technical Committee |
| COOLANT IN THE ENGINE OIL SUPPLY |
Coolant In The Oil On
Toyota 20R & 22R Engines
AERA members have reported instances of engine coolant mixing with the engine lubricating oil supply.
In some of these cases, pressure testing the cylinder block and head has not identified the source of the leak. However, close inspection of the aluminum front cover revealed an area where the timing chain wore through into a water passage.
In this engine the water pump is mounted to the front cover. When the timing chain stretches and the automatic tensioner is no longer able to take up the slack, the loose chain can slap against the front cover. Continuous contact will eventually wear a hole into the front cover, introducing engine coolant into the
crankcase.
The AERA Technical Committee |
| FLYWHEEL SPECIFICATIONS |
Flywheel Specifications
The following flywheel specifications may be used as reference
when surfacing flywheels.
Type of
Manufacturer flywh. Specs. Comments
BMW Step .013 - .015
Datsun Step .003 - .005 No groove
Flat With groove
Datsun 240Z Step .010 With groove
Fiat Spider 1600 Step .018
Ford Falcon Cup .018 6 Cylinder engines
Ford Courier Cup .285
Cup .310
Ford Ranger Cup .003 V6 Cylinder engines
GM Cup .125
GM - Buick Cup .125 V6 Cylinder engines
GM - Spirit Cup .195
Honda Cup .030 Small cup
Cup .100 - .104
Cup .785 Long alignment pins
Cup .900 Short alignment pins
Honda Accord Cup .615
Mazda Cup .062 Rotary engines
Subaru Cup .785
Toyota Step .018 - .022 Large alignment pins
Cup .055 Small cup
Cup .965 - .970 Tercel, large cup
Step .040 Tercel, step
Step .020 Land Cruiser
VW Cup .945 Air cooled, 6 Volt
Cup .830 Scirocco
Cup .835 Rabbit/Golf
Cup .982 Air cooled bus engine
Cup .830 Air cooled engine
Cup .885 Air cooled engine
Specifications listed for Step type flywheels refer to the
height of the wear surface above the pressure plate mounting
surface. Specifications for Cup type flywheels refer to the
height of the pressure plate mounting surface above the wear
surface.
The AERA Technical Committee
February 1988 - SB 153
##END## |
| VALVE LASH ADJUSTMENT ON 1998-2003 TOYOTA 1.8L ENGINES |
Valve Lash Adjustment For
1998-2003 Toyota 1.8L Engines
The AERA Technical Committee offers the following information regarding valve lash adjustment for 1998-2003 Toyota 1.8L engines. Beginning in the year 2000 Toyota offered two engines with the 1.8L designation. They can be identified first by a 1ZZ-FE (1762 CC) engine, and then a 2ZZ-GE (1794 CC) engine.
The valve lash specification for exhaust locations is different for the two engines. Refer to the chart below while adjusting valves for these engines.
Years Engine Location Specification
1998-2003 1ZZ-FE Exhaust .010-.014 (.25-.35 MM)
1ZZ-FE Intake .006-.010 (.15-.25 MM)
2000-2003 2ZZ-GE Exhaust .014-.018 (.35-.45 MM)
2ZZ-GE Intake .006-.010 (.15-.25 MM)
These engines use different methods of adjusting the clearance; the 1ZZ-FE uses one of thirty-five different thickness lifters, while the 2ZZ-GE uses one of forty-one different lash caps. The 1ZZ-FE also requires camshaft removal to facilitate lifter replacement (lash adjustment), whereas the 2ZZ-GE lash cap replacement to perform valve lash adjustment.
The AERA Technical Committee |
| VALVE SEAL IDENTIFICATION FOR TOYOTA 1.8L ENGINES |
Valve Seal Identification For
2000-2002 Toyota 1.8L Engines
The AERA Technical Committee offers the following information on valve seal identification for 2000-2002 Toyota 1.8L engines. Starting with the 2000-year model Toyota offered two 1.8L engines with similar displacement, a 1ZZ-FE and a 2ZZ-GE designation.
Determining which engine you're working on may be confusing, as many components are similar. Valve stem seals fall into the confusing category, as they physically appear the same at first glance. Original equipment and some aftermarket seals are color coded to ease in seal identification. Refer to the chart and Figure 1 below to help identify the seals once they?re out of their original packaging.
Engine Model Location Coloring Part Number Stem Diameter
1ZZ-FE Exhaust Gray 9008031046 .2152-.2157
1ZZ-FE Intake Light Brown 9091302101 .2154-.2159
2ZZ-GE Exhaust Green 9091302115 .2144-.2154
2ZZ-GE Intake Black 9091302114 .2150-.2156
Valve guides are also slightly different between the two engines, which offers additional means of engine identification. The installed guide height and the guide outside diameter are different as the 2ZZ-GE engine protrudes higher than the 1ZZ-FE. The 2ZZ-GE guides should be .602-.618 above the spring seat while the 1ZZ-FE guides should be .342-.358 above the spring seat.
The AERA Technical Committee |
| REVISED TIMING BELT & TENSIONER SPRING |
Revised Timing Belt &Tensioner Spring For
1992-96 Toyota 2.2L 5S-FE Engines
The AERA Technical Committee offers the following information on a revised timing belt tensioner spring for 1992-96 Toyota 2.2L 5S-FE engines. This information should be considered anytime the timing belt is removed from the engine.
The timing belt and tensioner spring for 5S-FE engines has been revised beginning with the 1997-year model. The timing belt and spring are designed for use, as a set and one should not be replaced without replacing the other. All 1992-96 engines should be updated with the revised spring and belt as a set for improved durability. Intermixing prior and revised components should not be attempted as improper tension and alignment may occur.
Prior Part Number Current Part Number Description
90507-18030 90507-17003 Tension Spring
13568-09040 3568-09041 Timing Belt
Its 4mm shorter length and additional 3 coils can identify the revised spring.
The AERA Technical Committee |
| Flywheel Assembly Revisions |
Flywheel Assembly Revisions On
1988-92 Toyota 4.0L Landcruiser Engines
Toyota has changed the flywheel assembly and crankshaft on 4.0L engines installed in the Landcruiser starting with the model produced in October of 1989. The revised engines carry an engine number of 3F-250226 or later.
The obvious difference between the former and the revised design is the flywheel bolts. Formerly these were 10x1.25mm bolts that were 32mm long. The revised bolts are 11x1.25mm and only 26mm long.
All of the components, including the crankshaft, are only interchangeable as a set. Be sure to verify the type of flywheel assembly and crankshaft that is being used when remanufacturing and installing Toyota 4.0L Landcruiser engines.
1988 through Oct. of 1989
Part Sep. of 1989 through 1992
Description Part Number Part Number
Flywheel Bolt 90105-10115 90105-11030
Crankshaft 13401-61021 13401-61023
Flywheel 32101-60010 32101-60011
w/gear
Spacer, Front 32116-60010 32116-60011
Spacer, Rear 32117-60010 32117-60011
The AERA Technical Committee |
| |
FEBRUARY TECHNICAL MAILING CONTENTS
To be completed by January 30, 2002
(Revised January 15, 2003)
1.Shop Talk (11 X 17 folded & punched) 12 Sides
2. EXPO 2003 Convention Brochure Pickup
3. EREF ? 2 Brochures Pickup
4. EREF ? Enrollment Form Pickup
5. Machine Shop of the Year Preprint 2 Sides
6. ES 287 Subaru 2.5L, DOHC, 1996-99 (11 X 17 folded & punched) 2 Sides
7. ES 288 Subaru 2.5L, SOHC, 2000-2003 (11 X 17 folded & punched) 2 Sides
8. TB 1937R GM, 6.5L Diesel, Engine Balance 1 Side
9. TB 2046 Mack MIDR, Improved Valve lifter 1 Side
10. TB 2047 Toyota 2.2L, Revised Timing Belt & Tensioner Spring 1 Side
11. TB 2048 Navistar 7.6 & 8.7L, Revised Con Rod Bolt Torque 1 Side
12. TB 2049 Navistar 7.6 & 8.7L, Revised Oil Seal Carrier & Gasket 1 Side
13. TB 2050 Ford 4.6L, Crankshaft Caution 1 Side
14. TB 2051 GM 6.5L, Alternative Piston 1 Side
15. TB 2052 Ford 3.8L, Crankshaft Caution 1 Side
16. Vanguard ShopKinks Flyer 2 Sides
H:\techsvcmonthlyTMC2_03.doc
Additional printing for January |
