I changed the rear crankshaft main bearing last time the engine was out to look for leaks.
Gonna do the front crankshaft main bearing now as well for the sake of completeness. Then (along with the big-end bearings) all 4 bearings are new.
But its a bit like opening Pandora's box... While I've got the sump off I'm having a little look at the Oil pump....looks bad.
The strainer was all bunged up with little hard black crud lumps. The long shaft that goes through to the water pump and the cog-wheel that drives it is all worn. According to the Fiat manual you measure the thickness of the shaft in 3 places with a micrometer - done that and its worn below Fiat's allowable tolerance in each place.
Then inside the oil pump there is a sort of arrangement where a 4 pointed star rotates inside a 5 pointed star. Well the 4 points are all damaged, with deep grooves, wear, and chips of metal missing.
On the 5 point star: the top flat side has a huge circular groove cut in it by something and a groove of the same shape is cut into the strainer housing where it bolts to the "5-star".
If you lift out the 5-star ring, you find that a bad grooved rut has been cut into the sump by something getting trapped between the 5 star ring and the sump.
Turning the sump the upside down to the waterpump side, it looks as though the waterpump has exploded in the past and been replaced. A big hunk of "liquid metal" type stuff has been added to the outside of the sump to repair a big hole in it where presumably the old impellor made a bid for freedom.
Don't want to dismantle any more parts its too depressing!
