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B21playa

Removing plenum e39 M5

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Hi all

 

Anyone got a guide to remove plenum fully, I’ve removed the upper bit and the tracts but don’t know where all the connections are and best way to do this.

 

pics of inside the plenum attachedimageproxy.php?img=&key=a752e9eef3625401imageproxy.php?img=&key=a752e9eef3625401

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CAB825DB-BC7E-4BE8-938C-BB8AF97149AB.jpeg

ED45B0F2-14FD-43A1-9705-FEF6E5ACE39E.jpeg

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You need to remove all the hex bolts surrounding the inlet pipes (velocity stacks or whatever people are calling them these days), undo the jubilee clamps off the air filter/inlet tubes and also remove the oil separators at the front. Should then just lift off from memory.

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Yep as JamesWSB says is correct.  It should lift off with no trouble once all the bolts are out and separators/air filter tubes removed, unless like mine it was silicone sealed down in the past :roll: 

 

The torque value on each of those bolts isn't much at all either when you reassemble.  Something like 10NM each.

Edited by DatV8

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Thanks both.

 

How are the oil seperators disconnected? I’ve got all bolts I can see off.

 

also any suggestions to cleaning throttle body

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Oil separators are just push fit on the bungs in the front,  once you've unbolted they'll pull out..  You can leave most of it connected up and it'll be enough to remove the plenum.

 

You can probably clean each inlet with a rag and carb cleaner, the throttle butterfly valves open from the throttle linkage in the middle V.  Of course make sure nothing falls inside as you're then removing the heads/using magnet tool to get anything out ;) You could remove the intake gaskets to fully clean these but they may be tricky getting back on again

 

 

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Has the car not been started in a while?  This can often be hydraulic lifter tick which goes away once warm and the oil pressure increases.  After a few weeks parked up I think most would exhibit that noise as oil drains out of the lifters.  It's pretty common.

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9 hours ago, DatV8 said:

Has the car not been started in a while?  This can often be hydraulic lifter tick which goes away once warm and the oil pressure increases.  After a few weeks parked up I think most would exhibit that noise as oil drains out of the lifters.  It's pretty common.

Correct it’s been sat for about a month now since getting the f10 and not getting around to stripping the plenum of e39 to check for broken vac pipes etc due to misfire. Also need to find this new coolant leak

Edited by B21playa

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Anything else I should do while I have plenum off? 

 

Noticed wetness around a few injectors, wondering whether to change seals or injectors seeing as car has 144k

Edited by B21playa

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1 hour ago, B21playa said:

Anything else I should do while I have plenum off? 

 

 

Could be a big list. A lot depends on how far you want to go 'while you're in there'. 

 

If I were to do just two things, as a bare minimum,  I'd replace:-

 

#16 here: http://www.realoem.com/bmw/enUS/showparts?id=DE92-EUR-09-2001-E39-BMW-M5&diagId=13_0819

 

 

#17 here: http://www.realoem.com/bmw/enUS/showparts?id=DE92-EUR-09-2001-E39-BMW-M5&diagId=13_0838

Followed by #14 and #16 on this same diagram. (#14 can give trouble sooner or later... but it's awkward to remove.)

 

I replaced most of the hoses I had access to under the plenum. The throttle position sensors (x2) also easier to access with the plenum off, ditto the cam position sensors (x4).

 

With the plenum off you will have very good access to the thermostat, so that might figure somewhere on your list too, if it's not already been done. With the thermostat out, replacing the narrow rubber pipes of the oil separator system is a cinch -  which are a bitch to change with the thermostat housing and plenum in place.

 

As I said, depends have far you want to get into it. At 144k miles there's quite a lot you'd be well advised to change if the car is a keeper.

 

M - the most expensive letter in the alphabet.

 

 

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Thanks

 

I’ve ordered vacuum hose, has a new brass elbow to replace the plastic one. Forgot I had TPS and CPS to install as well as lower oil seperator hoses. Thermostat has been done before I got it, but may need to be removed for the lower hoses, so need to get some o-rings but very expensive at the dealers. Any alternatives?

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The dimensions for the thermostat housing 'O' rings are revealed by Realoem, #9 & #18 here: http://www.realoem.com/bmw/enUS/showparts?id=DE92-EUR-09-2001-E39-BMW-M5&diagId=11_2667

 

What isn't revealed by Realoem is the material specification for the 'O' rings. I bit the bullet and coughed up at a dealer (Cotswold BMW), where a small discount was available. If you do decide to replace the thermostat then buy extra 'O'rings since most people screw up their first attempt. There's definitely a learning curve:-

 

https://forum.bmw5.co.uk/topic/134093-cool-runnings-e39-m5-thermostat-o-rings-learning-curve/

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On 27/05/2019 at 10:01, DepthHoar said:

The dimensions for the thermostat housing 'O' rings are revealed by Realoem, #9 & #18 here: http://www.realoem.com/bmw/enUS/showparts?id=DE92-EUR-09-2001-E39-BMW-M5&diagId=11_2667

 

What isn't revealed by Realoem is the material specification for the 'O' rings. I bit the bullet and coughed up at a dealer (Cotswold BMW), where a small discount was available. If you do decide to replace the thermostat then buy extra 'O'rings since most people screw up their first attempt. There's definitely a learning curve:-

 

https://forum.bmw5.co.uk/topic/134093-cool-runnings-e39-m5-thermostat-o-rings-learning-curve/

Thanks for that, thread is an interesting read. 

 

I've ordered some viton o-rings in the correct size, hopefully all with be ok. Got 8 of each due to minimum order quantity. Refurbished injectors also on order.

 

Still can not located coolant leak. Looking at the engine, the undertray is wet on the right hand side front

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Double check your hose clamps.  I had a leak down the front/right side of the engine, bought a coolant pressure tester (good purchase) and it turned out it was leaking at one of the hose clamps when putting 1 bar of pressure into the system.  Reseat the hose and all good now.  Coolant pressure testers are only around 40 quid on the bay so probably a worthy addition to the tool kit

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1 minute ago, DatV8 said:

Double check your hose clamps.  I had a leak down the front/right side of the engine, bought a coolant pressure tester (good purchase) and it turned out it was leaking at one of the hose clamps when putting 1 bar of pressure into the system.  Reseat the hose and all good now.  Coolant pressure testers are only around 40 quid on the bay so probably a worthy addition to the tool kit

I thought the hoses on the right were quick lock type

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They are at the radiator side but at the thermostat housing mine were replaced with standard screw clamps.  If yours are too then double check the hose is seated on the housing outlets correctly and the clamp is OK.  That was definitely were mine was leaking.  On the side under the oil filter housing also make sure you've not knocked the small coolant pump next to the chassis rail.  Should be hard lines there though but another possibilty.  It's used for the rest function to pump warm coolant in to the cabin when the engine is off I think

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Thanks, the thermostat housing side is screw clamp but it’s not leaking from there. Also checked the aux pump pipes under oil housing :cry:

 

Currently working through cam sensors, all done apart from bank2 exhaust and then bank1 tps. Refurbished injectors are due soon, just need to work out how to remove old one as well as throttle body gasket......the list continues with oil separator hoses after removing thermostat 

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Just noticed this pipe under passenger airbox that has a broken blue plastic connector. Can’t see where it should go or what it’s for. You can just about make out where coolant is pooling on undertray

2B474634-B860-45CD-8C82-3F8C004D9D7C.jpeg

Edited by B21playa

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Can't seem to find what that is on RealOEM either, wasn't aware of that.  Is it an overflow from the radiator that's broken off and has been placed there?  It also may not be a coolant pipe unless you can visibly see it dripping from that pipe?  Could be a vent for something.  You're probably best getting a coolant pressure tester to see exactly where it's leaking.

 

Where in the country are you?

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4 hours ago, DatV8 said:

Can't seem to find what that is on RealOEM either, wasn't aware of that.  Is it an overflow from the radiator that's broken off and has been placed there?  It also may not be a coolant pipe unless you can visibly see it dripping from that pipe?  Could be a vent for something.  You're probably best getting a coolant pressure tester to see exactly where it's leaking.

 

Where in the country are you?

 In Birmingham

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I'll have a look on mine as soon as I can and see what that pipe might be.  How much does the coolant reservoir level drop when left? (presume it's not running at the moment)

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Drops about a quarter, maybe less. First noticed it from a puddle under the car when I took it to work. Not running at the moment due to taking it apart to replace parts. Hoping to get it jobs done by end of weekend, enough to get it started again with plenum off

 

Appreciate if you could look.

 

Edit: just ordered a pressure tested off the bay, let’s hope it can track the source of the leak 

Edited by B21playa

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Had a look on mine earlier and I definitely don't have that hose under the passenger side airbox.  Only place I can think that's come from is the corner of the radiator where there's an overflow for the reservoir, maybe in a past life it's been broken off and just left.  Couldn't imagine that would leak much though

 

That'll do the job, will show up immediately then, keep us posted! B)

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