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Discussion Starter #1 (Edited)
I had some funky shifts on my 2007 M5 with 107k miles and was getting consistent 4fa0 (clutch position deviation) and occasional 4f40 (pressure undershoot) codes. The SMG pump motor sounded fine but seemed to kick on too often when pressure shouldn't be dropping, like after sitting for a minute at a stop light. I bought the $100 lower block seal kit from mlreng.com and 2 liters of CHF11S:

http://e36-electronic.com/photos/M5/IMG_4333.jpg


Lots of loose carbon inside the motor:

http://e36-electronic.com/photos/M5/IMG_5229.jpg


One of the brushes sticking:

http://e36-electronic.com/photos/M5/IMG_8339.jpg


Motor after partial cleanup:

http://e36-electronic.com/photos/M5/IMG_2987.jpg


Clutch valve o-rings not looking so great:

http://e36-electronic.com/photos/M5/IMG_6875.jpg



I was able to do the work without dropping the exhaust or lowering the transmission. I did have to unbolt the lower hydraulic block from the transmission using a very short allen wrench and carefully pulling it down a tad with the lines still attached to the top. I cleaned up the motor, lightly filed the stamping on the side of the brushes to prevent sticking, and re-assembled.

The motor was due for maintenance but I don't think that was the cause of the codes and jerkiness. I'm pretty sure the clutch valve o-rings were not sealing well. The pump used to run for over 10 seconds every time I opened the door but this morning after the car sat for 36 hours it ran about 2 seconds and I don't hear it coming on so frequently while driving. Shifting has greatly improved as well.
 

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When I did this job late last year I promised I'd take pics and post a DIY on how to refurb the pump motor. Now that weather is slowly improving I was planning on finally doing so, but there's little to add to your great post here. Just make sure you mark (sharpie works great) the alignment between brushes cap and motor body (magnet). The brushes to magnet alignment is critical on electric motors.

That stuck brush pic is exactly what causes motors to fail. Brushes only need a little trimming to allow them to slide freely.
 

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Discussion Starter #3 (Edited)
When I did this job late last year I promised I'd take pics and post a DIY on how to refurb the pump motor. Now that weather is slowly improving I was planning on finally doing so, but there's little to add to your great post here. Just make sure you mark (sharpie works great) the alignment between brushes cap and motor body (magnet). The brushes to magnet alignment is critical on electric motors.

That stuck brush pic is exactly what causes motors to fail. Brushes only need a little trimming to allow them to slide freely.
Thanks, I believe you (or someone else) had previously mentioned marking the body & caps to preserve alignment, so I did.

Time will tell, but I'm guessing the SMG motor will be good for another 100k miles. I'm not convinced anyone needs to replace the motor unless it failed for some other reason, especially now that the o-rings, reservoir clamp, and motor coupler are available separately.
 

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Hi gpeterson,

So although currently my shifts are fine and my SMG motor doesn't spin for that long when opening the car, I do get the 4fa0 error code every now and then so i'd be keen to change my clutch valve o-rings as you have and I might as well buy the seal kit and look at the motor too.

I would be grateful if you could confirm a few steps:-

I don't have a lift so will be jacking the car up and getting underneath and as you stated you didn't have to drop the trans, just dropping the hydraulic unit a little with the lines still attached.

: Did you drain all the hydraulic fluid out or did you just remove the clutch valve and allowed the fluid to drain a little when the valve was removed?
: When you replaced the clutch valve did you top the hyd fluid up to the refil port?
: Did you use ISTA/INPA tocarry out any bleeding procedures?
: I can't find the $100 seal kit on the MLR site could you link the product as i can only find the kit with the electric motor?

Many thanks
Jamie
 

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Discussion Starter #5
Hi gpeterson,

So although currently my shifts are fine and my SMG motor doesn't spin for that long when opening the car, I do get the 4fa0 error code every now and then so i'd be keen to change my clutch valve o-rings as you have and I might as well buy the seal kit and look at the motor too.

I would be grateful if you could confirm a few steps:-

I don't have a lift so will be jacking the car up and getting underneath and as you stated you didn't have to drop the trans, just dropping the hydraulic unit a little with the lines still attached.

: Did you drain all the hydraulic fluid out or did you just remove the clutch valve and allowed the fluid to drain a little when the valve was removed?
: When you replaced the clutch valve did you top the hyd fluid up to the refil port?
: Did you use ISTA/INPA tocarry out any bleeding procedures?
: I can't find the $100 seal kit on the MLR site could you link the product as i can only find the kit with the electric motor?

Many thanks
Jamie
I drained all of the fluid. The reservoir and pump have to be removed to get to the motor bolts. After re-assembly you need to fill, bleed/adapt (INPA or ISTA), then top up fluid again.

MLR doesn't list the hardware motor kit on the website, you can contact him at https://mlreng.com/pages/contact-us
 

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Can you guys elaborate on what kind of 'trimming' you do on the brush? Maybe highlight it in the pic above?
Thx
 

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Discussion Starter #7
Can you guys elaborate on what kind of 'trimming' you do on the brush? Maybe highlight it in the pic above?
Thx
You can't see in the picture, but if you slide the brushes out you will see letters/numbers stamped into the side. The stamping makes the edges of the digits protrude slightly. If you gently file them down the brushes will slide smoothly.
 

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I drained all of the fluid. The reservoir and pump have to be removed to get to the motor bolts. After re-assembly you need to fill, bleed/adapt (INPA or ISTA), then top up fluid again.

MLR doesn't list the hardware motor kit on the website, you can contact him at https://mlreng.com/pages/contact-us
Thanks very much for your reply thats a great help.

Cheers
Jamie
 

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Thx, doesn't the adaptation have risk?

I drained all of the fluid. The reservoir and pump have to be removed to get to the motor bolts. After re-assembly you need to fill, bleed/adapt (INPA or ISTA), then top up fluid again.

MLR doesn't list the hardware motor kit on the website, you can contact him at https://mlreng.com/pages/contact-us
I thought the SMG adaptation in ISTA can fail due to to other parts having issues thus leaving the car inoperable. Is that not the case with this adaptation?
 

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Discussion Starter #10
I thought the SMG adaptation in ISTA can fail due to to other parts having issues thus leaving the car inoperable. Is that not the case with this adaptation?
That is the case. I installed a spare SMG module and (successfully) ran adaptation on it first so that I would have still have an operable car if adaptation failed.
 

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Discussion Starter #11
One week of driving and no SMG codes, this definitely fixed my persistent 4fa0 for about $150 and a few hours of work.
 

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Guys, Im hoping someone can help with some hopefully quick answers, I just finished i clutch change and in the process i replaced all the seals in all the SMG solenoids and the Pump and block. I just topped off the reservoir with Pentosin and am attempting to ventilate (Bleed) the hydraulic block using ISTA. The process will not run however and I get a SMG relay fault. I replaced the relay and I’m pretty sure its working correctly. One thing to note, the first time I tried the procedure the Pump was very hot to the touch and was not making any noise. I expected the pump to turn on during the venting process but since this is my first attempt at this i'm not sure what to expect. Any thoughts? Could my pump be bad or is this normal during the venting?

Thanks!
 

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Sounds like the pump or motor is stuck, hence why motor was hot but you didn't hear it running. Did you open the pump? If the pump bolts are too tight it will get stuck. Someone reported this if memory is right.

Also there are 2 SMG fuses along the pump relay back row. Blue 15A and a big red 40A if memory is right. Check both. If pump or motor is stuck you likely blew the 15A fuse. Got to figure out why it's stuck tho.
 

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Interesting, I did open the pump motor, (not the pump) to clean it and check the brushes and clean the commutator. The pump was turning when i resembled but ill go back in and check the motor. Maybe i over-tightened the two long assemble bolts? Ill also confirm the Fuses are good. Thanks, that definitely helps point me in the right direction!
 

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Check the coupler as well. Someone had trouble with it, can't remember specifics. Try hooking up 12V straight to the motor and see if it runs (motor out that is). Since you didn't mess with the pump I'd look at the coupler too. The long motor bolts are not an issue IMO. Maybe the motor to gearbox brackets are pushing the motor out of alignment?
 

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+1 for the coupler. I also remember this member on the board who installed it incorrect and pump was stuck.
Also myself, I experienced hard time to match the electric motor shaft - coupler - pump, and it took me some time and effort.
good luck
 

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Thanks Guys! Yep, I installed the coupler wrong and the slots were not lines up correctly. Surprised it is even able to be mounted that way but i guess the screws that mount it are long enough to engage the block. I wound up checking both fuses, they were good. Checked voltage to the pump motor with the relay installed, good. Then powered the motor from a spare 12 volt battery. worked perfectly. Very carefully lined up the slots on the pump with the coupler and re-installed. Its not obvious when its fully seated but it did feel more secure when i tightened down the screws. Ran the block vent, slave cylinder vent and measured the pressure which started at 65 bar before settling at 35 bar as the measured preload. Reinstalled the drive shaft and exhaust, Just need to do the clutch adaptation. One more good day and this car is back on the road!
 

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That was me, I really struggled with the coupling. I had to dress the edges and use some grease to hold it in place. If you don't hear the motor during the bleeding process check the coupling!
 

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Do any of you know what are the sizes of the o-rings for the clutch shift solenoid ?

i know the thickness should be around 1.6mm and 75 durometer

but no idea what the OD and ID measurements are. Are they the exact same sizes as Vanos o-rings ?
 

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I have a new set left over from my SMG reseal a couple months back. Not sure how i ended up with an extra set but in measuring the 4, each looks exactly 1 millimetre difference in diameter. ID of the smallest is 11mm, then 12mm, then 13mm and the last is 14mm. I believe you are correct on the thickness at 1.5/1.6. If you would like to measure for yourself i can send you this set as long as you return them.
 
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