isuzubob
23rd July 2009, 01:38 AM
The spigot bearing (AYG320) for the LT95/LT85 when behind the Isuzu 4BD1 sits inside a recess in the rear of the crankshaft & utilises a bronze bush instead of a deep groove ball bearing when the Isuzu gearbox is used as fitted to an Isuzu truck.
http://img210.imageshack.us/img210/1954/isuzu4bd1009.jpg
The bronze bush (R549911) is a wearing item & quite easily removed. Unless badly damaged whilst removing the bush there is generally no need to replace the spigot housing itself. In this case an LR-spec 4BD1 engine was being exchanged with an ex-Isuzu NPR59 4BD1T and therefore needed the LR type housing removed. Unlike other LR engine spigot bearings, such as V8 & 300Tdi, the rear end is solid & the usual removal methods using toilet paper or grease would not work.
The housing is a very tight press fit into the rear of the crankshaft. After applying gentle heat with an oxy heating tip and stopping the crank from turning at the front using a socket and breaker bar a plumber's Stillson (pipe wrench) was used to rotate the bearing housing & "crack" the seal. Two flywheel bolts were then inserted into the crank, avoiding the flywheel locating dowel, all the way. A suitable heavy duty washer was sourced, pressed flush against the bolt heads and welded onto the housing.
http://img520.imageshack.us/img520/8784/isuzu4bd1010.jpg
The two bolts were then simultaneously unscrewed, slowly forcing the washer & housing out. More gentle heat was applied
http://img9.imageshack.us/img9/5250/isuzu4bd1013.jpg
and a sharp tap on the edge of the washer helped as the bolts were being undone, eventually freeing the housing.
http://img9.imageshack.us/img9/504/isuzu4bd1015.jpg
Fortunately this job rarely needs to be done and a complete new spigot bearing is only around $60.
Rob W
http://img210.imageshack.us/img210/1954/isuzu4bd1009.jpg
The bronze bush (R549911) is a wearing item & quite easily removed. Unless badly damaged whilst removing the bush there is generally no need to replace the spigot housing itself. In this case an LR-spec 4BD1 engine was being exchanged with an ex-Isuzu NPR59 4BD1T and therefore needed the LR type housing removed. Unlike other LR engine spigot bearings, such as V8 & 300Tdi, the rear end is solid & the usual removal methods using toilet paper or grease would not work.
The housing is a very tight press fit into the rear of the crankshaft. After applying gentle heat with an oxy heating tip and stopping the crank from turning at the front using a socket and breaker bar a plumber's Stillson (pipe wrench) was used to rotate the bearing housing & "crack" the seal. Two flywheel bolts were then inserted into the crank, avoiding the flywheel locating dowel, all the way. A suitable heavy duty washer was sourced, pressed flush against the bolt heads and welded onto the housing.
http://img520.imageshack.us/img520/8784/isuzu4bd1010.jpg
The two bolts were then simultaneously unscrewed, slowly forcing the washer & housing out. More gentle heat was applied
http://img9.imageshack.us/img9/5250/isuzu4bd1013.jpg
and a sharp tap on the edge of the washer helped as the bolts were being undone, eventually freeing the housing.
http://img9.imageshack.us/img9/504/isuzu4bd1015.jpg
Fortunately this job rarely needs to be done and a complete new spigot bearing is only around $60.
Rob W