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DerekJr.

Engine Replacement (M52TU)

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I think my engine has finally given up after +320k miles. I think I hear a rod knock but I will investigate it further over the weekend. My engine is the M52TUB25 found in the later pre-facelift 523i. A friend who breaks E39s has an M52TUB28 found in the later pre-facelift 528i. I know the engine will be a direct fit (replacing an M52TU with another M52TU).

 

However, is there anything else that I will need to know before swapping them over?

> I've heard of EWS delete etc and using keys from the donor car. Can I just remap my existing engine software to a 528i map?

> Would you recommend removing the transmission with the engine and then splitting it, or splitting before engine removal?

> What other items will I need from the 528i donor car?

 

I'll appreciate any other advice you can offer if I have missed something out

 

Thanks in advance

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That sounds like fun. Put my milage into the list. Seems to be the highest for now .

 

When I had my m54 engine out I left the gearbox and the exhaust line in the car. Enough space to pull the engine. I had the intake manifold off which made it easy to get to the transmission bolts on the back of the engine. Just make sure the torque converter stays in the tranny:

IMG-20200229-104838860.jpg

Edited by Johan

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Speak to Kyle at dts tuning, he can just delete the ews off the 528i ecu or could map it for you too! I’ve had one for my 530i great fella 

 

you can send him any m52tu/m54 ecu and he’ll tailer it to your needs 

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I thought I would post an update on this:

 

Firstly, thank you for your insight and ideas. Really appreciate it and it has helped me!

 

Secondly, progress is being made albeit slowly. I'm tackling the engine transplant after work on weekdays and on weekends, mainly on my own. Nevertheless, progress is progress! The engine was delivered 1-2 weeks ago and the car was moved from the street to the underground parking last Friday where I am tackling the job. I managed to limp it to the location with the engine ticking away. In my head, I thought:

 

Friday: Move the car to the underground parking after work, and get started removing items and loosening bolts in the evening.

Saturday: Remove the old engine and fit the replacement engine. 

Sunday: Tidy up and take the e39 to an E39 meet at Ace Cafe

 

However, this is the first time I'm tackling a job this large on the e39 so I'm taking it easy. So an engine transplant over a weekend didn't go as planned. Due to me removing the engine from the transmission while in the car, I had to remove the intake manifold, to gain access to the gearbox bolts on the top. This added more time to the process. However, the silver lining to this is that I can remove the starter motor which gives me access to remove the torque converter bolts. It is easier compared to using the access port by the exhaust side of the engine, especially if you are planning on leaving the gearbox on the car. Most people use this access port by the exhaust once they have the engine + gearbox combo out of the car. 

 

So, what is the progress so far?

- Engine hoist delivered and assembled 

- Remapped (claimed 207 bhp and EWS deleted) 528i DME delivered

- Separated the exhaust from the manifold (thankfully none of the bolts snapped or seized)

- Loosened all gearbox to engine bolts, ready for removal (thankfully none snapped or seized)

- Loosened engine mount bolts

- Intake manifold removed

- Starter motor removed

- Removed torque converter bolts

 

What's left to do?

- Drain coolant and oil

- Disconnect some coolant pipes

- Remove all relevant bolts and nuts

- Remove bonnet 

- Lift engine 

 

It's a learning curve but I am enjoying it so far. I can see the light at the end of the tunnel. I feel like my e39 knowledge is getting bigger and bigger! Hopefully, the old engine will be out by this weekend and the replacement engine will go in. I can't wait to have cold A/C again. My other car needs its A/C condenser replaced so these past few days have been a nightmare with this heat. The other issue is that its average MPG is currently sitting at around 12 lol.

 

Edited by DerekJr.

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Update:

 

The old engine has now been removed from the car tonight :) Hopefully, the new engine will be up and running by the weekend. 

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Update:

 

The replacement engine was put in the car on Saturday. On this day I also decided to do the hard jobs (gearbox to engine bolts, torque convertor to flex plate bolts, exhaust reattachment). Yesterday (Sunday) I reinstalled the radiator, intake manifold, and reconnect the wiring harness with the remapped ECU. I also decided to replace some of the clips for the power steering reservoir so that should fix my leak. The engine fired up and I drove the e39 around the block. All seems well although I'll need to renew the valve cover gasket as it's seeping oil onto the exhaust manifold judging by the smoke it's producing. Mentally and physically exhausting but a good exercise, nevertheless. 

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Get M54B30 intake manifold and throttle body adapter. +10BHP. M52TUB28 has a very restricted intake manifold (same as 2 litre engine). Also replace Vanos seals and add LM Ceratec. You can also do an engine tune to use all that extra breathing you will get. It has transformed mine (eMaps - Simon) 

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