Tom's E60 550i Manual Project

[lellowcake]

Hi All,

New to the forum (never been on a forum before, so you might have to bear with me a bit!) and wanted to start a thread to show my current project - A 2006 E60 550i factory manual. A little bit about how I ended up with it:

In 2018 I bought a 2005 E60 535d in a bit of a hurry, it turned out to be the perfect car for me at the time, it was pretty cheap, pretty economical, pretty fast, comfortable and practical. I ended up driving it round Norway for 3 weeks (pic below - sorry, never been great with a camera, my pics won't do anything any justice) about a month after buying it, had a great time and the car worked great.

A couple of months later I ended up gong travelling and was away from home for a few years and the 535d was left un-used. During that time I spent a year in Australia, where I bought a 1995 Toyota Landcruiser FZJ80 - which was without question the best car with the most memories attached to it that I have ever owned and I wish I had the resources at the time to import it back home. I bought it for £2500, fixed it and fitted it with everything I needed to live out of it with a limited budget and it took me everywhere, never let me down and did things that a tired 400,000Km car in standard form, mostly on bald, dry rotted tyres with everything I owned at the time and needed to live shoved in the back of it had any business doing. The pic below is of it on Fraser Island, next to the SS Maheno wreck - I've got thousands of pics I still need to go through.

After coming home from Aus I was back living in London again only to find this thing called 'The ULEZ', which meant it was no longer viable for me to drive the 535d. Keen to do my bit to help the environment I decided to get rid of my 3.0 litre diesel and buy a 4.8 litre petrol which is complaint somehow (I don't make the rules 🫤), a 2006 E60 550i with a factory manual gearbox in late 2022. Long story short, I wanted an M3 or M5, but with my budget would have been looking at the lower end of the market and it would have just been a disaster, so the 550i was the best compromise between what I wanted and what I could practically have. It had 70,000 miles, and quite a rare spec (in the UK anyways) with a manual gearbox and looked to be pretty good car. Below are some quick pics I took with my phone after me and my brother gave it a quick mint up the other day. On closer inspection the car had such low miles because it had spent so much time written off, the previous owner (turns out the son of the car dealership I bought it from) had then done some of the worst bodge jobs I have ever seen and repaired it badly to get it sold - everything he has touched has 1 out of 4 bolts left in it, the radiator was cabled tied in, along with most of the front end and too many other bodge jobs to mention, the door and boot don't really fit except to look correct from the outside, all of the bodywork was fixed so badly that most of the paint over repairs started to fall off within about 2 months (although it does look ok in the pics). 'New clutch just fitted' apparently means that there's a clutch in the boot ready to go on - too many annoying problems to mention. AlI that said, I am not mechanic myself (as you will find out), but hope I can do a better job of it. I probably should have looked a bit closer before buying the car, but it really did look ok on the surface and I would not have found another car like it. During the time I have owned it I have spent time fixing some of the endless bodge jobs doing general maintenance and have taken it on some longer trips like surfing in Cornwall, climbing and mountain biking in Wales, a stag do in Liverpool and do really like the car. Some of the more interesting things I have done (shown in the bad phone pics below) include upgrading the brake pads, lines and fluid, fitting 'semi slick' tyres, wheel spacers and stud conversion, polybushing the subframe and diff mounts and the most recent job (I'll get into in a bit) was to fit a 'racing' thermostat. The pics also show the exhaust system that came fitted to the car, it's custom made by Longlife and sounds really good in my opinion, if a little loud, along with some insulation from a motorbike fairing I added the other month as it sits quite close to the battery tray and spare wheel well.

The cream/beige interior is in quite good condition and has grown on me a bit:

Dissapointing-looking engine bay:

EBC Yellowstuff pads and calipers re-furbed by myself and Darkside wheel spacers (15mm front and 20mm rear):

Yokohama Advan AD08RS tyres and stud conversion:

EBC braided brake lines and Hyperflex subframe polybushes:

Longlife cat-back exhaust system:

As I mentioned earlier, the most recent job I did the other day was to fit a Mishimoto 'racing' thermostat. The electric fan seemed to be running flat out all of the time the car was running, so read the fault codes to see a couple related to the engine coolant thermostat. I normally try to upgrade parts as I fix them and had seen mixed opinions about fitting lower temp thermostats (i.e. thermostats that open at a lower temp) to the N62B48 engine - some say that it won't run efficiently if it's too cold, some say that the standard one makes the car run far too hot and will damage it over time. I believe the standard thermostat opens at 105C, the one most people it opens at 95C, I realized after doing some digging that a thermostat from an F80 M3 would fit (there are basically no performance parts available for this car, it seems), that Mishimoto made one for that model and that it opened at 100C - in my eyes the best compromise as I do want to use the car for track use and more spirited driving, but mostly it is my daily driver. So I ordered up the parts and on one of the rare sunny days in during the UK winter fitted them, as mentioned I am not a mechanic and am learning as I go and am more than open to suggestions - this is not a how-to guide:

I started by removing the tray under the engine to find the drain on the driver's side of the radiator and drained it, jacking the car up at an angle to help get us much coolant out as possible. I realize that there is another drain on the engine block, however from what I have read and after a quick look, these are a nightmare to get to, will have been through countless heat cycles and despite this not being the technically correct way to do it, decided that this was hassle I could do without:

The coolant that came out:

I then went about removing the engine covers and induction pipe from the airbox to the throttle body to reveal the thermostat. I'm thinking of permanently removing the engine covers as the inlet manifold looks better than loads of plastic in my opinion, if anyone has any reason why I shouldn't, please let me know:

The big throttle body and engine not looking as low-mileage as I would like:

This allowed me to undo the 3 bolts holding the therostat on. Below is the therostat I removed - it appears to be original and in good condition, I'm not sure if it has a mechanical fault or a fault with the temp sensor:

The old and new thermostats side by side:

The new Mishimoto thermostat:

Which I then fitted with the supplied gasket after cleaning up all the bolts, mating surfaces, hoses and electrical connectors:

I wanted to use coolant system flush, but because I believed that the thermostat was not opening and would not allow it to properly circulate round the engine, I decided to do it after I had fitted the new thermostat, I used de-ionised water and some flush from Wynns. Basically just followed the instructions, filling the cooling system and then driving the car to get the car up to temp and then draining as much coolant as possible using only the radiator drain plug:

Coolant after the first flush and drain:

Because I had loads of de-ionised water, I repeated the process with just water to get rid of any remaining flush:

After a third flush using only de-ionised water the fluid looked like this:

I had noticed that the coolant capacity is just shy of 14 litres and each time had to top up around 7 litres, meaning that I was removing around half the coolant each time I drained it. As the new coolant required a 50/50 mix with de-ionised water and the coolant above to my eye was pretty pristine and basically just de-ionised water now, that I would just add neat coolant to what was left in the engine and call it a day - please tell me if I'm wrong, like I say, I am not a mechanic. I also added some Mishimoto Liquid Chill coolant additive. Again, I've seen mixed opinions, my understanding is that it is supposed to get rid of microbubbles in the coolant meaning better heat transfer as coolant is far more efficient at transferring heat? Either way I added it, thinking that every little helps. Coolant used was Motul Autocool Expert Ultra:

The Liquid Chill is weird looking - orange in the bottle, but appears blue/purple when poured:

I put all the covers/ducts back on, made sure there was no air in the system, checked the levels later when the car had cooled to make sure there where no leaks. There weren't, the fan was no longer permanently on and the fault codes where gone.

If you made it this far through me rambling and all the boring pics of various dilutes of coolant in a bucket, cheers for reading! The overall plan with the car is to keep it maintained, fix the remaining annoying bodge jobs, make sure the car can safely handle more power in terms of cooling itself, drivetrain, reliability, handling and stopping. Eventually I would like to find some sort of up-rated clutch, single mass flywheel and LSD solution that doesn't cost a fortune and to get the car to 400bhp, which might be difficult given the lack of aftermarket parts available for the 550i. The main plan however, is to use the car - I bought it to be a fun, fast daily driver that I could happily do the occasional track day in, drive across europe for mountain biking, climbing and trips to the Nurburgring etc. Like I say suggestions welcome and I'll do my best to keep this updated with my progress.

Cheers, Tom. 🙂

 

 

 

[DJ Syxx]

Welcome to the forum Tom and nice to see another N62 owner and project.

There is a handful of manual 550i and are very rare with that gearbox.

That is an interesting find with the F80 M3 thermostat and then I realised that the thermostats for the N62 also fit them as they are the same! This also means that the F80 and other models run hot too. Be interesting to see in time when they get older what happens to the oil seals and cooling system.

You mentioned about the 90c ones being not efficient from what you read. I've not seen much info on that but have seen some hit and miss posts depending which 90c thermostat you get. The ones from Turner Motorsport and ECS tuning are mixed. I bought mine from Electrorefit which is spot on and doesn't trigger any error codes.

I still think running a lower 90c is beneficial for the engine and from what I've read on this and with Streten from M539 restorations fitting a 90c one in project Alpina, it just makes sense.

Be good to see more progress on this. Have you got a sound clip of the exhaust?

PS As a hobby mechanic myself, you done well mate. Keep it up.

Edited January 10 by DJ Syxx

[lellowcake]

Thanks Mate 🙋‍♀️

I haven't seen another manual 550i yet - to be fair it would be quite an odd choice to make at the dealership.

I read your project thread right after I posted my own and if I'd have known about the thermostat you fitted, I probably would have fitted the same, being that they are basically genuine BMW ones - I can definitely see the logic in running a cooler thermostat.

There's a long list of stuff to do on the car and I enjoyed recording it, so expect more! I'll defo get some exhaust clips and some better pics as soon as i figure out a way to record them properly - it's quite loud...

Cheers for the kind words!

[olliecampbell]

Lovely looking machine. If only it was a touring then I'd be in love!

 

 

Looking forward to more updates