| CYLINDER BLOCK IDENTIFICATION ON M60 ENGINE |
Cylinder Block Identification On
BMW 4.0L DOHC M60 Engines
The AERA Technical Committee offers the following information cylinder block identification on BMW 4.0L DOHC M60 Engines. BMW used two different cylinder wall-finishing processes during production, which are called Nikasil and Alusil. Each block is fit with pistons and piston rings especially for the cylinder bore finish and never should be interchanged.
Nikasil is an aluminum alloy block with nickel dispersion-coated cylinder bores and was used on the M60 engines and replacement blocks. Nikasil version incorporates crosshatch hone marks in the bore finish. Alusil is an aluminum silicon alloy used in M60 replacements and M62, M70 and M73 engines. Alusil version has smooth gray cylinder bore finish without cross hatch marks.
A quick way to know what type of cylinder block you have is by the casting number. Block casting numbers are located on the right side of the block next to the coolant drain bolt.
Casting Number Cylinder Block Version
1725970-1714212 M60 B30 Nikasil
1745871 M60 B30 Alusil
1725963-1742998 M60 B40 Nikasil
1745872 M60 B40 Alusil
1745873 M62 B44 Alusil
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## |
| OIL FILTER CAUTION FOR BMW EXTENDED OIL CHANGE ENGINES |
Oil Filter Caution For
BMW Extended Oil Change Interval Engines
The AERA Technical Committee offers the following information regarding an oil filter caution for extended oil change interval engines. These engines, the M52TU, M54, M62 and M73 may be affected if the proper oil filter element is not used when extended oil filter intervals are endured. BMW has offered this extended 15,000-mile interval service to certain high performance vehicles only if the service is implemented by a BMW dealer. This extended interval period also mandates the use of specifically formulated synthetic engine oil obtained from BMW.
A new oil filter element has been developed for all BMW models with extended service intervals (approximately 15,000 miles). This filter must be used whenever an oil service is performed on an extended oil change interval engine. The new oil filter element incorporates improved filter paper, which prevents filter deterioration caused by high engine oil temperatures over extended time. The new oil filter element was phased into production on M54 powered vehicles in September of 2000 and on all M62 and M73 powered vehicles in July 2000.
Using any other filter or engine oil in these engines may prove harmful to the engine if the filter paper deteriorates before filter replacement. At this time BMW approves no other filter or oils for use on these engines.
The AERA Technical Committee |
| REVISED CYL HEAD MOUNTING COMPONENTS & PROC |
Revised Cylinder Head Mounting Components and Procedures on
BMW 1983-86 325e and 528e (VIN M20B25 and M20B27) Engines
AERA has received many calls on leaks of the cylinder head to block joint and cylinder head bolt breakage on BMW M20 series engines (applicable to all displacements). The following revised components and procedures should eliminate these difficulties for AERA members and their customers.
A revised cylinder head gasket with improved sealing should eliminate oil seepage between cylinders No. 3 and 4 on the exhaust side of the engine. A .012 (.3mm) thicker head gasket should be used when cylinder block deck height or cylinder head minimum thickness specifications are exceeded.
Previous Head Gasket 11 12 1 278 305
Standard Head Gasket 11 12 1 708 891
Oversize Head Gasket 11 12 1 713 493
Revised cylinder head bolts of increased strength and hardness along with a new torque procedure should further reduce head gasket problems. The revised cylinder head bolts are easily identified by their Torx heads and black finish. BMW recommends installation of the revised bolt whenever the cylinder
head is serviced. Bolts should be replaced as a complete set available under the Part #11 12 1 726 478 (14 bolts).
Use the following torque procedure on the revised bolts:
1) Torque all bolts to 22 lbs.ft. (30 Nm)
2) Turn all bolts 90^
3) Turn all bolts an additional 90^
The waiting and running time requirements used with previous procedures no longer apply.
The AERA Technical Committee |
| COOLANT IN THE ENGINE OIL SUPPLY |
Coolant In The Engine Oil Supply On
1991-93 BMW 1.8L Engines
AERA members have reported coolant in the engine oil supply on 1991-93 BMW 1.8L engines. The cause of this condition may be the result of a deteriorated front cover gasket and/or the erosion of the timing cover mating surfaces. That leakage may allow engine coolant to pass around the gasket and enter the engines oil supply. This condition may also show evidence of external coolant leakage at the engine's front timing cover aera.
In most instances, if the cover is leaking externally, it is also leaking internally. Ignoring a slight amount of external leakage, may lead to extensive engine damage if it is also leaking internally.
Vehicles built after approximately 10/1/93, have a revised optimized rubber material composition and reduce the possibility of this problem occurring.
To repair a metal erosion condition, BMW authorizes the use of a metal epoxy type repair to the gasket mating surfaces of either the cylinder head or timing cover. Many AERA shops have been successfully welding those areas.
The AERA Technical Committee |
| OIL SEEPAGE FROM THE CYLINDER HEAD |
Oil Seepage from Cylinder Head On BMW 1991-93 1.8L Engines
The AERA Technical Committee offers the following information regarding oil seepage from cylinder head on BMW 1991-93 1.8L engines. This engine is referred to as M42 and is used in 318 I vehicles.
Oil seepage may occur from the left side of the cylinder head at the lower mounting bolt. The cause of the oil seepage is due to a casting shrinkage
cavity. It is located between the M6 threaded hole for the timing chain tensioning rail mounting and the M8 threaded hole for the intake manifold support
bracket, as shown in Figure 1.
To correct this problem on M42 engines produced since April 1993, the lower bolt for the intake manifold support bracket has been installed with 3 Bond 1209.
It is also marked with a black paint spot.
This repair procedure applies if oil seepage is evident coming from the lower mounting bolt # 1 as shown below. To repair, remove the bolt and degrease
the bolt threads (#2) and bolt hole threads. Then, apply liquid sealing compound 3 Bond 1209, BMW Part # 07 58 9 062 376 on the bolt, reinstall bolt and torque to 12-13 ft/lbs.
The AERA Technical Committee |
| COOLANT LEAKS ON 1988-90 5.0L ENGINES |
Engine Coolant Leaks On
1988-90 BMW 5.0L Engines
AERA members have reported engine coolant leaks on 1988-90 BMW
5.0L engines. The coolant seems to be coming from the coolant
chamber cover on top of the engine block due to a distorted
cork gasket.
BMW now offers a new style gasket, Part # 11141736959, to
reduce the possibility of this problem. The new gasket is made
of a plastic-coated paper, which is colored green. Anytime a
repair or a replacement of a part is done, this new gasket
should be installed.
As of September 1989 production, the coolant chamber cover was
modified to improve the gasket contact surface by widening the
sealing lugs around the boltholes. When a new style cover is
installed on a vehicle prior to September 1989 production, make
sure that the wider bolt hole lugs on the cover do not contact
the engine block.
The old style cork gasket, Part #11141288979, is no longer
available individually. The old style cork gasket is included
in the engine block gasket set and must be replaced with the
new rubber gasket.
AERA is currently unaware of an aftermarket supplier for this
revised gasket.
The AERA Technical Committee
January 1999 - TB 1648
##END## |
| COOLANT LEAK FROM CYLINDER HEAD ON 2.8L M52 ENGINES |
Coolant Leak from Cylinder Head On
1995-2000 BMW 2.8L M52 TU Engines
The AERA Technical Committee offers the following information regarding a coolant leak on 1995-2000 BMW 2.8L M52 TU engines. This leakage has been located at the front right side of the cylinder head corner directly below the BMW insignia cast into the head.
Coolant Leak from Front Right Side of the Cylinder Head
APPLICABLE MODELS AFFECTED:
Z3 2.8L and 2.3 with M52 TU engines produced from 9/99 - 10/99.
E46 328 and 323 with M52 TU engines produced from 9/99 - 10/99E39 528 with M52TU engine produced from 9/99 - 10/99
Apparently some cylinder heads were cast with a machining flaw (hair line crack) and may have been installed on M52 TU engines in production on a limited number of vehicles. The leakage has been observed to be in the area indicated by the black arrow in Figure 1 below. The machining flaw (if present) is located in the front right side of the cylinder head and will cause a coolant leak in the area of cylinder head to block joint.
Figure 1.
Parts required to repair this condition are listed in the table below.
Figure 2.
The AERA Technical Committee |
