Thread: How to remove 4BD1 spigot bearing housing

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.



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.



The two bolts were then simultaneously unscrewed, slowly forcing the washer & housing out. More gentle heat was applied



and a sharp tap on the edge of the washer helped as the bolts were being undone, eventually freeing the housing.


Fortunately this job rarely needs to be done and a complete new spigot bearing is only around $60.

Rob W

think i'll try this method tomorrow after drilling and tapping through the nose, then proceeding to brake the bolt off that was used to push against the crank, then proceeding to snap an easy out in said bolt