Table of Contents
Advertisement
Plus d'informations sur : www.dbmoteurs.fr
Main Bearing
Bearing surfaces
Inspect each bearing shell for abnormal contact such
as scratching, corrosion, flaking, etc. Also check for
signs of poor seating in the bore of the crankcase or
bearing cap.
Bearing thickness
Use a ball point micrometer to measure the center of
each hearing shell. If the service limit is exceeded on
any of the shells, replace the upper and lower shells
as a set.
Main bearing thickness (center) STD, mm [in]
Nominal value ........... 4.500
Assembly standard ... 4.467–4.480
Service limit .............. 4.425
Main bearing thickness (center) –0.25 [0.0098],
mm [in]
Nominal value ........... 4.625
Assembly standard ... 4.592–4.605
Service limit .............. 4.550
Main bearing thickness (center) –0.50 [0.0197],
mm [in]
Nominal value ........... 4.750
Assembly standard ... 4.717–4.730
Service limit .............. 4.675
Main bearing thickness (center) –0.75 [0.0295],
mm [in]
Nominal value ........... 4.875
Assembly standard ... 4.842–4.855
Service limit .............. 4.800
Main bearing thickness (center) –1.00 [0.0394],
mm [in]
Nominal value ........... 5.000
Assembly standard ... 4.967–4.980
Service limit .............. 4.925
NOTE! Four undersizes are available for the main
bearings; -0.25 mm [-0.0098 in], -0.50 mm [-0.0197
in], -0.75 mm [-0.0295 in] and –1.00 mm [-0.0394].
Replace main bearings.
If the thickness exceeds the service limit, either re-
place the main bearings as above, or refinish the
crankshaft and use undersize bearings.
Group 21 Engine Body
[0.17717]
[0.17587–0.17638]
[0.17421]
[0.18209]
[0.18079–0.18130]
[0.17913]
[0.18701]
[0.18571–0.18622]
[0.18405]
[0.19193]
[0.19063–0.19114]
[0.18898]
[0.19685]
[0.19555–0.19606]
[0.19390]
135
Advertisement
Table of Contents
