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Correct!
This is a quote from JColley on another post concerning priming the smg hydraulic pump:

"Did you prime the pump after reassembly before trying to bleed it? If not, your block is air-bound. There is a check valve internal, on the discharge of the pump. If you haven't purged the air between the pump discharge and the check valve, the pump can't create enough pressure to open the check valve and commence flowing fluid.

There is an aluminum drain plug on the bottom of the hydraulic block underneath the pressure and temp sensors. Unscrew and remove that plug. Activate the pump in DIS/INPA/ISTA/Whatever until fluid issues from the bottom of the block. Turn the pump off, replace the drain plug. Now the pump is primed and you can run the bleeding process."

Hope this helps you.
 

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Discussion Starter #22
Correct Jcoley word's!
Even with this nothing at all......
No pressure!!
Open everything again and check the orings!!
2 of them is wrong.....pffff
I put again the original and put it back....
Still the same
Now I'm trying the clutch slave cylinder ventilation with the screw under the block few turns open!
Probably after some times fluid comes out???
According ista yes... any suggestions??
 

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In order to prime the pump you have to remove the bottom plug completely, then activate the pump via ISTA until you get fluid pouring out the plug hole. Then only you re-install the plug. If you only unscrewed it a bit this won't work. I suggest you check the level of the pentosin again after you have primed the pump, if there is not enough in the tank after the system is primed, there is no chance the pressure will build up in the accumulator.

Lack of pressure is:
Lack of fluid
Unoperative/weak pump. How were the collectors on your pump motor?
Deffective accumulator, seems very rare.
Deffective seal, oring or whatever, you checked it.
Deffective solenoid piston, that is internal leak, needs replacement of the solenoid unless you have the facilities to rebuild a cartridge.
Deffective solenoid coil.
Clutch cylinder leak,
Deffective sensor or harness
You name it
As you say, dismanteling every thing for no result is waste of time and money. Plus it is frustrating...




Silly question maybe, what about your pressure sensor? once you have primed the pump, even if the pressure does not build at full working pressure you should read something on ISTA, not zero! When you depressurize the system, ISTA reads 1bar, which is atmospheric pressure, not zero.
 

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Discussion Starter #27 (Edited)
Hello!!!

Sorry for the delay of reply but i start working again and my time is limited.

YEEESSS i fix it!!!

My big mistake ..... when i reassembly the electric motor , accidentally rotate the body with the magnets to find the "way" for the bolts.....
When you have a DC motor like this one , when you rotate the body also rotate the polarity!!!!! So the motor turn from the opposite direction :eek:eek:eek:eek:eek

I figure my mistake when i take out all the unit from the car and put it to my bench and just give 12v to the motor! When i connect it opposite , immediately the pump charge the accumulator !!!!
So i rotate the body and everything work perfect !!
Put everything back to the car start ISTA and pressure is back!!! Bleeding start normal and finish with 64 psi from 27psi that i have before!!!!!!!!
I big smile at my face :grin:grin:grin:grin

Now the pump need only 5 seconds to build the pressure when i open my door! The gears is faster and smoother , without delays .
Electric motor is stronger with total different sound.

My only disappointing is the clutch issue that is still there !! 99% i need PLCD sensor.

Information to all.....

O-Rings dimensions FOR THE SOLENOID ( Viton high temp and oil resistance )

11.5 X 1.5

12.5 X 1.5

13.5 X 1.5

14.5 X 1.5


all the others is easy to find so i dont keep the numbers
 

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Great to read you solved the priming problem. Sure it is better if the motor is turning on the right way! It is an interresting feedback though on what could go wrong when reassembling this DC motor.

Thank you very much for the dimensions I assume the diameters are outside diameters.
 

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Discussion Starter #29
All the job is pretty easy if you have tools , instructions/torque , otherwise you need a lot of hours!!

The diameters is inside always!! The external diameter is determined by the thickness
 
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