When to replace an oil pump?

[Psychomofo]

Okay, I'm doing the M30 swap. I've got the motor, and I'm replacing some gaskets and things before it goes in. Should I go ahead and replace the oil pump, or not? The motor has about 150,000 miles on it. I could save myself 250.00 american dollars if I didn't replace it, but I'm just not sure of how long the existing pump will last. Any input on this?

[Jos]

Oil pump failures on the M30 are rare, in saying that both Toby_Unna and Andy335itouring have both had theirs fail..

You will probably find it is cheaper just to buy another M30 engine and have it sitting spare on the offchance that the pump does go. 150k is not a lot of miles on these engines provided they have been moderately well looked after.

I am changing my oilpump but only because I am also changing the sump, probably go dry sump tbh.

[Psychomofo]

Okay well that's reassuring. I'll probably check out the pump and make sure everything looks okay with it, but I'll probably just not buy one for right now. Although, it will be a pain to change later on.

[Toby_Unna]

not sure about that

andy's engine failed on one cylinder only so i think a blocked oilway rather than bad pump

on mine the nut securing the drive sprocket to the pump undid itself and the pump lost drive. not a pump failure, hadn't been put together properly at some point i guess

both euro e34 535i engines. i'd take it apart and look at the surfaces of pump lobes and inner housing, they won't be perfect but if look ok then maybe re-use it. pump is more expensive over in uk, about Ԛ£220.

what m30 are you using?

[Psychomofo]

I'm using a motor from an '89 735i.