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93 525 Paul
03-09-2010, 10:08 PM
Found this in the archives about removing the M30 engine.
Same or diffierent with the M50? Bentley says remove tranny from under car first, then pull engine. Was tempted to pull just the engine and leave the tranny in place.
What convertor or pump issues are raised with separating and joining?


See my tranny problems post.

You absolutely want to remove the engine and tranny as a unit, still bolted together. I wish I had. Seemingly, it would be easier to just take out the engine, saving myself the trouble of disconnecting the propeller shaft and exhaust, etc.. That's the theory.

In truth, if you separate the two, then try and put them back together in the car, you will have trouble getting to the 11 perimeter bolts on the bellhousing, which in itself makes separating the engine from tranny off the car worthwhile. Access to such bolts turned out to be the least of my problems.

Sadly, there are other issues, such as potential damage to the torque converter and/or tranny pump, which can happen either/both during separation of the engine from tranny or upon rejoining them.

Far better, and less work in the long run, to remove them as a unit, then separate them once the TC is secured and you have access to the bellhousing bolts. You'll also have better access to properly retorque those bolts when out of the car.

Using a leveler is a wonderful idea, as is removing the radiator and hood, neither of which takes much effort.

Thanks in advance

yaofeng
03-10-2010, 01:19 AM
Pull the drive train as a unit. I always do.

http://i21.photobucket.com/albums/b274/yaofengchen/BMW_95_525i/DSC_6757.jpg

Dave M
03-10-2010, 02:52 PM
I've done it twice, both times separately. Next time (god forbid), I'll try takingthe whole thing out in one piece.

Dave

whiskychaser
03-10-2010, 05:18 PM
What convertor or pump issues are raised with separating and joining?
TC should stay in the tranny. Make sure you spin it and push it back in so it seats correctly. Otherwise you will do some damage when you bolt up.
Some very sound advice here:
http://www.europeantransmissions.com/Bulletin/important_torque_converter_insta.htm
If you are taking the engine out anyway, save yourself a lot of grief and take the tranny out with it.

93 525 Paul
03-16-2010, 11:44 PM
If you are taking the engine out anyway, save yourself a lot of grief and take the tranny out with it.

Thanks, did that. On my domestics I've always just pulled the motor, glad I asked, yanking it intact wasn't too bad. Did it as a one man job, the only part of the whole removal process that was a two man job was pulling the hood.
Have a look...
http://i123.photobucket.com/albums/o284/pmcdougal/BeemerEnginePull.jpg
Major oil leaking mother fletcher. The worst one seems to be at the back passenger side corner of the head to block and the front of the vc was terrible as well.

whiskychaser
03-17-2010, 11:56 AM
Great stuff! Have a look at the bell housing to motor bolts. And the bolts that hold the flex plate to the TC (you have fish for them through the peep hole). Imagine trying to undo them with the motor in place:D And then trying to line up the tranny and motor to mate them again while lying on your back.:D

93 525 Paul
03-17-2010, 01:55 PM
Great stuff! Have a look at the bell housing to motor bolts. And the bolts that hold the flex plate to the TC (you have fish for them through the peep hole). Imagine trying to undo them with the motor in place:D And then trying to line up the tranny and motor to mate them again while lying on your back.:D

Whisky you have been a big help all through this deal. Thanks for that. I read about that in the Royce/Bentley manual but haven't gone there yet. What are the 3 big bolts accessible through the starter hole? They look like flexplate to TC to me but, at this point my instincts are useless.

I'm still haunted by that $2k 99 M3 Motor on Craigslist...

whiskychaser
03-17-2010, 02:51 PM
Whisky you have been a big help all through this deal. Thanks for that. I read about that in the Royce/Bentley manual but haven't gone there yet. What are the 3 big bolts accessible through the starter hole? They look like flexplate to TC to me but, at this point my instincts are useless.

I'm still haunted by that $2k 99 M3 Motor on Craigslist...
You are very welcome! The bolts are not through the starter hole. Look for a rubber bung in the rear motor flange. Its about 2" diameter. If you are standing in front of the car looking towards the windscreen, it will be at about 25 mins to the hour. You remove the bung and if you turn the motor you will see the heads of the bolts line up with the hole. Imagine looking for them with the front subframe in the way:D If you are putting the auto back in, then I strongly recommend you use some loctite on those bolts. They dont need to be super tight but you dont want them cutting loose either

93 525 Paul
03-17-2010, 09:08 PM
You are very welcome! The bolts are not through the starter hole. Look for a rubber bung in the rear motor flange. Its about 2" diameter. If you are standing in front of the car looking towards the windscreen, it will be at about 25 mins to the hour. You remove the bung and if you turn the motor you will see the heads of the bolts line up with the hole. Imagine looking for them with the front subframe in the way:D If you are putting the auto back in, then I strongly recommend you use some loctite on those bolts. They dont need to be super tight but you dont want them cutting loose either

Will do. That part of the assy is caked with road grime from the leak directly above, so I haven't found a bung yet. Off to get the scraper...

paul p (chi-town)
03-17-2010, 11:21 PM
Imagine trying to undo them with the motor in place:D And then trying to line up the tranny and motor to mate them again while lying on your back.:D


Doing it on a 3er looked even worse. This is why i ended up farming out Rolf's clutch to a shop while the NX was DIY ...... solo.

Hang up & Drive!
94 BMW 530iT&A 155K, ‘Helga’ ( TRUSUV 5 & future kinder schleppen )
92 BMW 325i 179K, ‘Rolf’ ( On it's 3rd set of FCA bushings & still the cleanest )
93 Datsun NX2000 190K ‘Carla’ ( Flakey starter & rust gapes )
85 Toyo MR2 140K ‘Jerry’ ( Track toy & much more fun than a Prius )

“When the going gets weird, the weird turn pro."
- Hunter S. Thompson

93 525 Paul
03-18-2010, 12:45 AM
You are very welcome! The bolts are not through the starter hole. Look for a rubber bung in the rear motor flange.

Hey Whiskey, not to sound like an ungrateful tango whiskey alpha tango, but the convertor bolts are in fact accessible through the starter hole. Not that it matters much, few are dropping the tranny after you have all the top end bits removed, but thems is the facts.
I did find the bung, yes, with the crossmember right in the way and let's say a need to drop the tranny with the motor in the car, a real beast.


(Also, new photos of the carnage on the other thread.)

whiskychaser
03-18-2010, 07:15 AM
Hey Whiskey, not to sound like an ungrateful tango whiskey alpha tango, but the convertor bolts are in fact accessible through the starter hole. Not that it matters much, few are dropping the tranny after you have all the top end bits removed, but thems is the facts.
I did find the bung, yes, with the crossmember right in the way and let's say a need to drop the tranny with the motor in the car, a real beast.


(Also, new photos of the carnage on the other thread.)
If I have the inclination to change my tranny a third time I will check:D
I would say that if you drop a bolt using the 'peephole' you can retrieve it. If you drop it down the starter hole you might be parting the tranny again to get it out;)

93 525 Paul
03-29-2010, 04:12 PM
Great stuff! Have a look at the bell housing to motor bolts. And the bolts that hold the flex plate to the TC (you have fish for them through the peep hole). Imagine trying to undo them with the motor in place:D And then trying to line up the tranny and motor to mate them again while lying on your back.:D

The TC was so tight in the crankshaft it would have come out with the engine. Mating those 2 in the oddly large but still tight in spot confines of that engine bay would have been truly a bear.