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Discussion Starter · #1 ·
Hi, im new in the forum and im from Mexico, I will try to explain in better way my situation, I recently replace the motor pump from my e63 m6 due to stuck motor and no gain more pressure, yellow trans indicator came on, after opened all the unit, replaced the motor, orings etc, I assembled everything again put new chf11 to the top and I did the bleed block procedure with some air into the reservoir and activate the pump loosening the bottom check valve bolt as jcolley mentiones. Now insta register 58 bar and stays. My problem is when I run the slave bleeding procedure the pressure drops instantly and the bleeding process is cancelled. What is causing the pressure drops too fast into the system if my pump pressure reading is good enough to bleed the entire unit? Fluid level is at maximum, no leaks in all components. Am I missing somethig? Thanks for your help
 

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I did the bleed block procedure with some air into the reservoir and activate the pump loosening the bottom check valve bolt as jcolley mentiones.
The above procedure is not the Block bleeding, it is just a procedure to help the pump build up initial positive pressure. The block bleeding is a shift block procedure to vent the shift pistons block and shifting solenoids, you suppose to perform shift block bleeding after the slave bleeding.

Assuming the installation is fine or the check valve disturbance didn't cause an issue, raise the rear of the car then perform the slave bleeding and see what happens.

If you run the pump manually by the software, does the pressure goes up to 85-90 bar?.
What software are you using?.
 

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Discussion Starter · #3 ·
The above procedure is not the Block bleeding, it is just a procedure to help the pump build up initial positive pressure. The block bleeding is a shift block procedure to vent the shift pistons block and shifting solenoids, you suppose to perform shift block bleeding after the slave bleeding.

Assuming the installation is fine or the check valve disturbance didn't cause an issue, raise the rear of the car then perform the slave bleeding and see what happens.

If you run the pump manually by the software, does the pressure goes up to 85-90 bar?.
What software are you using?.
When I run the pump with ISTA the pressure value is 57-58 bar, finally the car start up and the clutch bleed procedure was concluded, but when I try to bleed the solenoids, the program cancel at the moment. I dont know if I have to try bleeding many more times or am I missing something.
 

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finally the car start up and the clutch bleed procedure was concluded
Good.
when I try to bleed the solenoids, the program cancel at the moment
Venting the shift block always PITA, just keep trying, there is much entrapped air in the system. You can help that by shifting gears manually by the software, drive the car around with frequent shifting and re vent the system.
When I run the pump with ISTA the pressure value is 57-58 bar
This is an issue. Manual pressure build up by ISTA should go to 90 bar, not reaching that pressure could indicate a leak in the pump internally, pump outlet seal, reservoir installation (pump inlet or seal), or check valve (where bleed screw is) not seated properly. Start the car and push the SMG sitting button to 5 bars and monitor the maximum pressure the system build, the SMG control unit should command the pump
motor to build pressure to 75+ bar.
Did you disturb the pump replacing the internal seal?
Perform accumulator manual test by disconnecting the SMG relay or the orange big fuse and monitor the pressure drop, the pressure figure when it suddenly drop to 0 is your preload pressure, record that.
 

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Discussion Starter · #5 ·
Good.

Venting the shift block always PITA, just keep trying, there is much entrapped air in the system. You can help that by shifting gears manually by the software, drive the car around with frequent shifting and re vent the system.

This is an issue. Manual pressure build up by ISTA should go to 90 bar, not reaching that pressure could indicate a leak in the pump internally, pump outlet seal, reservoir installation (pump inlet or seal), or check valve (where bleed screw is) not seated properly. Start the car and push the SMG sitting button to 5 bars and monitor the maximum pressure the system build, the SMG control unit should command the pump
motor to build pressure to 75+ bar.
Did you disturb the pump replacing the internal seal?
Perform accumulator manual test by disconnecting the SMG relay or the orange big fuse and monitor the pressure drop, the pressure figure when it suddenly drop to 0 is your preload pressure, record that.
Thanks for your reply!, but i dont understand exactly what are you refering to "Start the car and push the SMG sitting button to 5 bars" where is that button? In addition, my gear pump was damaged because of rest of metal sediments in fluid, then I replace a used block with the gear pump atached to it and both are in working conditions according to the seller. The only thing I did, was screw the new electric motor to the used block and to the gear pump, the gear pump was never opened like a sandwich. After screw everything i run the pump with a battery to suction a little of chf11 and preload the accumulator then i put the reservoir and fill 3/4 of capacity and continue running the pump till the fluid came out of the check valve bolt at the lower side of the block and tight it, after that I mounted all the hydraulic block, screw the slave cylinder line and solenoids line. Now this is the part that i dont know if i did well, I put some air into the vent valve of the reservoir, while I was putting the air at the same time I run the pump and unscrew a little the lower bolt of the block and the fluid starts coming out again but with so much force, stop the pump, the air and I screw all the lower bolt and tight it. I check the pressure and the maximum reading was 58 bar, accumulator is warm, the block is warm and run the slave bleed procedure which was ok. What I notice is when the car start and shift the gear, the pressure sometimes stay in 50 bar, then build instantly to 71bar then shift again to 2nd gear drops to 34 bar, stays there then I select all the shifts manually with insta and the read drops to 20 and 10 bar but the motor pump doesnt start, then the car dies beecause of low pressure and the clutch engage, I remove the key, put the switch potition on and the pump runs again by itself but no more gain of 54 bar.

Pd. The car never had problems with solenoids, the car show the red gear indicator on dash and insta says low pressure, the pump never activate even with the ista. Manually I remove it and see that the rotor of the electric motor was stuck due to carbon build up. Thats the reason why I replace only the electric motor and the gear pump due the metallic evidence in fluid.

I hope you to understand i tried to be the most clear , thanks a lot.
 

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i dont understand exactly what are you refering to "Start the car and push the SMG sitting button to 5 bars" where is that button?
Gear shift Automotive design Vehicle Audio equipment Car


Now this is the part that i dont know if i did well, I put some air into the vent valve of the reservoir
Put air from the fill screw. Once you have pressure no need to manually pressurize the reservoir.
You can try again to loosen the lower screw and start the pump, once the pressure comes out stop the pump and tighten the screw to reseat the check valve.
hen build instantly to 71bar
I can rule out the gear pump, this is the reason I asked to press the SMG sitting button to 5bar on dash which is S5 sitting so the SMG control unit command for more pressure build up and it seems the gear pump is doing its job.
then build instantly to 71bar then shift again to 2nd gear drops to 34 bar
Now this is the main issue.
I asked you to test the accumulator to rule it out, do it manually as I instructed in my previous post.
The other possibility is you have a leaking solenoid, you may damaged one of the O'rings while replacing them. Other possibility is leaking/damaged regulating shifting solenoid in the top block. You may need to inspect these next.
Did you swap the lower and the top block when you found metal sediment?.
 

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Discussion Starter · #7 ·
View attachment 959720


Put air from the fill screw. Once you have pressure no need to manually pressurize the reservoir.
You can try again to loosen the lower screw and start the pump, once the pressure comes out stop the pump and tighten the screw to reseat the check valve.

I can rule out the gear pump, this is the reason I asked to press the SMG sitting button to 5bar on dash which is S5 sitting so the SMG control unit command for more pressure build up and it seems the gear pump is doing its job.

Now this is the main issue.
I asked you to test the accumulator to rule it out, do it manually as I instructed in my previous post.
The other possibility is you have a leaking solenoid, you may damaged one of the O'rings while replacing them. Other possibility is leaking/damaged regulating shifting solenoid in the top block. You may need to inspect these next.
Did you swap the lower and the top block when you found metal sediment?.
Ok, i will try to loose the lower aluminum bolt and start again the pump. Next I will try to put the 5 bars selection and see how is the pump pressure. And about the swap I only change the lower block not the top one. Maybe the solenoid from the lower block could damage an oring I will inspect aswell. And i couldnt find the test of the accumulator you wrote in the forum how is that process? Thanks platii!
 

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And i couldnt find the test of the accumulator you wrote in the forum how is that process?
There is a test for the accumulator built in the software but the result will not be reliable when I am suspecting a major leak and in that case the software will not perform the test properly, instead I have given instructions to test accumulator manually without software input, you only use the software to read and monitor pressure drop, all you have to do is pull the SMG relay so the SMG motor doesn't come on when pressure reach below 50 bar, monitor the pressure drop, the pressure will keep dropping gradually until at some point it will drop instantly to zero, the point that pressure dropped to zero is the figure we need to determine the accumulator preload pressure. This monitoring process may take around 20 minutes. So be patient and don't wink lol.
 

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Discussion Starter · #9 ·
That test how many bar should the accumulator reach on the initial pump start? I guess i have done that test but with launch software. And as you say the pressure only reach to 55-57 bar and drops by itself to 33 never goes to zero.
 

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That test how many bar should the accumulator reach on the initial pump start?
I am not sure if I understood what you have asked but let me answer, on a low SMG sitting i would expect to see pressure at 65 bar.
drops by itself to 33 never goes to zero.
Hmm, doesn't leak beyond 33 bar, let's see, I really don't want to do that because I don't want inference from possible clutch valve or slave leak, ok when it stops at 33 give it 10 or 15 minutes if it didn't drop press the brake pedal once if it didn't drop to zero press again, do that until it suddenly drop to zero or explain what happens until the pressure get depleted. Record the pressure every time before you press the brake pedal so we can estimate the preload pressure. Ignition must on during this trial so the slave could actuate when you press the brake pedal.
 

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Discussion Starter · #11 ·
I am not sure if I understood what you have asked but let me answer, on a low SMG sitting i would expect to see pressure at 65 bar.

Hmm, doesn't leak beyond 33 bar, let's see, I really don't want to do that because I don't want inference from possible clutch valve or slave leak, ok when it stops at 33 give it 10 or 15 minutes if it didn't drop press the brake pedal once if it didn't drop to zero press again, do that until it suddenly drop to zero or explain what happens until the pressure get depleted. Record the pressure every time before you press the brake pedal so we can estimate the preload pressure. Ignition must on during this trial so the slave could actuate when you press the brake pedal.
Ok, ill do that and record the pressure. I will tell you what happened thanks a lot!
 

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Discussion Starter · #12 ·
Ok, ill do that and record the pressure. I will tell you what happened thanks a lot!
And about the initial pump start, i mean when you open the door and listen the pump activation for 6 seconds , how many bar pressure should the scanner read before start the car? Because in the morning I register 58 bar and sometimes 61, this before start the car. And after starting the car let the engine warm, make some shifts to D, N, R, D, M, 1, 2nd gears. The pressure start to drop a little to 40's bar then if the car is in D when the pressure drops to 30 bar and constantly to 25 bar the car dies due the clutch engagement. I dont know what happen but is like the motor pump doenst activate when the pressure continues droping. In addition when the car dies in gear I remove the key wait for a few minutes, and put the key again and switch on, the pump activates again the pressure build up to 55 bar and put in Neutral again but the pressure stay in 50's.
 

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And about the initial pump start, i mean when you open the door and listen the pump activation for 6 seconds , how many bar pressure should the scanner read before start the car
Normally 65 bar.
The pressure start to drop a little to 40's bar then if the car is in D when the pressure drops to 30 bar and constantly to 25 bar the car dies due the clutch engagement
There is a leak or still lots of entrapped air in the system, car shut down is normal to happen because the clutch no longer able to be open when the speed decreases.
When pressure drops below 50 the SMG control unit senses that and log a faults 4F40 and possible 4FA0 and no longer activates the pump unless you reset the system. Post the fault detail, if you using ISTA scan for fault and double click on each fault and choose details.
the pressure build up to 55 bar and put in Neutral again but the pressure stay in 50's.
This is low even for the lower SMG sitting. Do the manual accumulator test and post the faults details then we can decide.
 

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Discussion Starter · #14 ·
I am not sure if I understood what you have asked but let me answer, on a low SMG sitting i would expect to see pressure at 65 bar.

Hmm, doesn't leak beyond 33 bar, let's see, I really don't want to do that because I don't want inference from possible clutch valve or slave leak, ok when it stops at 33 give it 10 or 15 minutes if it didn't drop press the brake pedal once if it didn't drop to zero press again, do that until it suddenly drop to zero or explain what happens until the pressure get depleted. Record the pressure every time before you press the brake pedal so we can estimate the preload pressure. Ignition must on during this trial so the slave could actuate when you press the brake pedal.
Ihave change the orings from the slave cylinder solenoid and after that I activated the pump and reach 56 bar pressure, I waited 15 min as you indicate and doesnt drop, then i press the brake pedal and drops to 50 bar and stay there. Then about another 5 min again I press the brake pedal and drops to 46 bar and wait for another 5 minutes and doesnt drops, after I press again the brake pedal and drops to 43 bar and stays, the next sequence is exactly the same as above and then reading values were everytime I press the brake pedal 41 bar, 39,37,36, 36, 34, 33, 30, 8, 4, 3 and finally the pressure drops to zero. It doesnt appear like there a leak or what you think?
 

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So the accumulator is working just fine when pressure dropped from 30 to 8.

Another indication of hydraulic leak is you mentioned that the pressure drops rapidly when shifting gears, a good manual test to see if the shift solenoids are leaking is to manually shift to each gear and after the gear engage reach down and listen for any fluid flowing or hissing noise, if there is hissing noise then the solenoids are leaking, this leak could be causing the issue if the motor and pump are ok. Normally when the system has a light leak in the shift solenoid the pump will run more frequently to compensate but if the solenoids leak badly the leak will not be recovered and the system will drop to below 50 bar and more and the system will be locked and will not allow the pump to pressurize the system again until next reset.
 

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Discussion Starter · #16 ·
So the accumulator is working just fine when pressure dropped from 30 to 8.

Another indication of hydraulic leak is you mentioned that the pressure drops rapidly when shifting gears, a good manual test to see if the shift solenoids are leaking is to manually shift to each gear and after the gear engage reach down and listen for any fluid flowing or hissing noise, if there is hissing noise then the solenoids are leaking, this leak could be causing the issue if the motor and pump are ok. Normally when the system has a light leak in the shift solenoid the pump will run more frequently to compensate but if the solenoids leak badly the leak will not be recovered and the system will drop to below 50 bar and more and the system will be locked and will not allow the pump to pressurize the system again until next reset.
Exactly, I think theres a solenoids leak because theres is a fluid noise after the clunck noise when shift up gears and is engaged, in fact the reverse is more noisy. I will shift manually and see the drop bar pressure and report here. So, the next step is change all the solenoids orings of every gear? Or should I replace the entire solenoids unit which is on the upper side of the transmission?
 

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the next step is change all the solenoids orings
Do this. Just the O'rings, when you remove the solenoids inspect their tip for damage/cracks. I would suggest you replace the slave or at least switch its studs so the nuts are on the outside just in case you need to replace it later so you don't need to drop the transmission again. It is also worth to have a look at the gear position sensor wiring harness for insulation degradation while you are in there. You would need electrical wiring shrink tubes to repair it.
 

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Discussion Starter · #19 ·
Do this. Just the O'rings, when you remove the solenoids inspect their tip for damage/cracks. I would suggest you replace the slave or at least switch its studs so the nuts are on the outside just in case you need to replace it later so you don't need to drop the transmission again. It is also worth to have a look at the gear position sensor wiring harness for insulation degradation while you are in there. You would need electrical wiring shrink tubes to repair it.
Okay ill check that after I remove the transmission, do you have a link where i can buy those orings or slave? Because my only option is ebay and world of seals store but never they offer exacly the size of the oring.
 
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