Engine Swap - Questions, tips & advice

[westoz3.0csa]

G'Day All,

I have come into possession of a complete (from Flywheel to fan) M30B30 from a '94 Euro E32 730i (60K miles).

I was able to hear the motor running and do compression test (180-185 PSI on all cylinders)

I was just going to use it as a parts motor and swap out the FI to my
carbed motor .. but .. I have decided the better confused option is to just do a complete swap and store the original motor.

I would like to avoid any problems or surprises .. so .. my queries are ...

1) Will this motor bolt straight in, as is ? If not what do I need ?
2) Anybody that may have done this or similar swap (M30B35? from
similar era) got any tips or advice ?
3) Is there anything you would recommend I should do to the motor
before I swap it in ? ie: seals, bearing etc
4) What fuel pump could I use or is recommended ? ie, whats fits my
tank ?

As always any advice is greatly appreciated

Carl

'74 3.0CSA

 

[x_atlas0]

These questions have been answered many, many times on the forum and in the tech section in great detail, but here's the short version:

1. Mostly. There will be some motor mount plate bolt pattern differences on one side. (I suppose the driver's side over there) There are conversion plates available from several sources or you can make your own. It is pretty straight-foreward. You would also lose the mechanical fuel pump, since the head has no provision for it.

2. It is a fairly common swap, but as you mentioned, most just go for the M30B35 instead. The M30B30 of that era will be exactly the same aside from the displacement, so any previous threads, notes, FAQs and the like will apply. Firstfives has an excellent swap FAQ and there are many threads detailing the process here and in the tech archives.

3. Replace the water pump, rear coolant junction gasket, rear main seal, oil pump, and oil pan gasket. Also spring for new ignition components. (rotor, cap, wires, coil) Pretty much look for leaks with the engine out and fix it then, it is much easier to deal with.

4. You will need to fab a fuel return line that goes from the engine bay to the tank. For the pump, I just use the external pump/filter combo pack used on all M30s from the late 80s on. Works like a champ and no monkeying with the fuel tank or finding expensive OEM in-tank pumps.

The biggest difference for you compared to the vast majority of other swaps is that you are RHD. This means you will have interesting exhaust routing and may or may not have to deal with the Motronic/stock brake booster problem.