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SMG Experts: Issue with Clutch Bleed

23K views 241 replies 7 participants last post by  Boise567 
#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
 
#2 ·
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?.
 
#3 ·
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.
 
#10 ·
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.
 
#15 ·
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.
 
#16 ·
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?
 
#21 ·
That kit should fit.

Look at post #15

Lots of good SMG info here:

Place to find O'rings
 
#22 ·
That kit should fit. Thanks! The orings arrive in 15 days, ill report you how goes the repair.

Look at post #15

Lots of good SMG info here:

Place to find O'rings
 
#25 ·
I will do that tomorrow, what i notice is when I run the car and drive around the neighborhood the car drives in D and shift so slowly also the clutch engage is slow but if I try to drive in Manual mode with full 5 bar button, drive logic 1 shows the pressure drop to zero instantly and the pump doesnt start by itself even if the pressure drops slowly when the car is still driving. The relay can be doing any problem related to the pump activation?
 
#26 ·
When the pressure drop instantly the SMG will block pump motor activation so I don't think it is the relay. The leak rate increases with pressure and shift speed increase., something is leaking or air in the system. keep driving around and wait an pressure hold improvement, if no help then there is a leak somewhere.
Show Analog 3 with ignition ON and then brake depressed.
 
#27 ·
When the pressure drop instantly the SMG will block pump motor activation so I don't think it is the relay. The leak rate increases with pressure and shift speed increase., something is leaking or air in the system. keep driving around and wait an pressure hold improvement, if no help then there is a leak somewhere.
Show Analog 3 with ignition ON and then brake depressed.
Before I replace the orings the car shown reads of 56-65 bar pressure in every gear 1st to 7th when driving and never drops to zero, after i replaced the orings the initial pump pressure is no more of 48 bar in cold and 46 in hot weather, start the car and drive in 1st and 2nd gear around only in DRIVE mode and the pressure shows read of 39- 38 - 36 bar pressure then drops to zero again. What could be causing that droping pressure?? It supouse to increase pressure after replacing the orings and now the car is worst 😵 I put them carefully with petroleum grease and all the solenoids got in to the block smoothly without any problem.
 
#33 ·
Exactly, the system never reach more than 65 bar in the initial pump when open the door or if I try to activate manually that was the max pressure. But curiously when i druve the car in D or Manual all the shift engage perfecly and the car never got engaged in gear at a stop light.

And yes, the orings were from ebay especially for smg solenoids. Finally as you say I felt a little resistance when i was pushing inside all the 6 solenoids carefully.

I will keep trying bleeding more times and report if theres good news. Thanks
 
#35 ·
To be honest this test is not conclusive if the pressure drop to 0 suddenly. Will try later when the pressure improve.
Did you replace the pump internal seal on the replaced mechanical pump or opened it open?. If extensive bleeding didn't solve it you need to re inspect the pump and the pump inlet and outlet O'rings, have these O'rings been replaced?. Since the leak worsen after the O'rings replacement this could be because of weak pressure source, the source couldn't push the air out and bleed the system.
 
#36 ·
To be honest this test is not conclusive if the pressure drop to 0 suddenly. Will try later when the pressure improve.
Did you replace the pump internal seal on the replaced mechanical pump or opened it open?. If extensive bleeding didn't solve it you need to re inspect the pump and the pump inlet and outlet O'rings, have these O'rings been replaced?. Since the leak worsen after the O'rings replacement this could be because of weak pressure source, the source couldn't push the air out and bleed the system.
The gear pump was replaced due to metal sediments on the reservoir, and the new pump which is used but in working conditions i didt opened and inspect the internal seal with heart shape. Because once is opened to close it i dont know exacly the 2 bolts torque. The inlet seal is already replaced but the internal heart seal not.
 
#37 · (Edited)
Do you refer to inlet seal is the seal between the reservoir and the pump?.

Torque the pump to 5 Nm.

Pump outlet O'ring.
Font Circle Automotive lighting Auto part Metal


Desperately and if necessary I would remove the check valve and have a look at it. I would remove it slowly the last threads if there is a spring that would push down to keep track of parts sequence if it constructed of more than one part. Look for anything suspicious or O'rings and then put back. Give the clutch valve solenoid a second look, no O'rings torn during replacement.

Did you perform Clutch slave bleeding separately as mentioned before.
 
#38 ·
Do you refer to inlet seal is the seal between the reservoir and the pump?.

Torque the pump to 5 Nm.

Pump Inlet O'ring.
View attachment 961713

Desperately and if necessary I would remove the check valve and have a look at it. I would remove it slowly the last threads if there is a spring that would push down to keep track of parts sequence if it constructed of more than one part. Look for anything suspicious or O'rings and then put back. Give the clutch valve solenoid a second look, no O'rings torn during replacement.

Did you perform Clutch slave bleeding separately as mentioned before.
The inlet seal I ment to the little oring you put in red square in the photo, it is the oring between the gear pump and the block. And also i replaced all the orings from the reservoir.

Do you have any picture of the removal process of check valve from the block?
 
#42 ·
hello I'm going to get in here because I have exactly the same problem. platti brought me here :) . As I said in the other post, I have a new pump motor, renewed the seal from the gear pump, renewed the seals on the solenoid valves, and refilled the pressure accumulator with gas. the accumulator test is now a good 44 bar. but I only get 60 bar with the hydraulic pump and can't learn on the actuator block. now the question is the problem with venting?? because the error on the controller block says pressure build-up was not done in time. because air in the system? or is there something wrong that he doesn't build up enough pressure? does the error point to the 60 bar? that it's not enough? because for me the pressure drops immediately to 0.7 after 2 switching processes, that can't be normal
 
#44 ·
I'll try it again on the car with inpa and rheingold in the next few days. I recently replaced the seal on the solenoid valves and didn't test it again. I have to wait for a friend who has this program inpa. but the seals looked good before i change it, I'm curious what the test will do this time, I'll tell you about it then. i hope you understand me well with my english i come from germany :)
 
#46 ·
You can use ISTA no problem to bleed the clutch separately 5 times, then bleed the block several times. You can manually activate the gear shifts with ISTA or INPA to help bleed the system then you can bleed again the block.

If you use INPA follow the direction in the above thread to bleed the clutch first individually several times then bleed the block.

platti this seal i don't know 100 percent but i think the mechanic just put it in and not in the groove like in the picture
That seal has nothing to do with pressure, you can call it dust seal.
 
#51 ·
i also charge my late original bmw battery which has 900a and the new battery has 850a don't know if it could be the problem that it mostly only has 60 bar. but with the new battery the contact cannot be screwed on properly i don't think the car gets all the power. I'm now loading the old original BMW battery and will test it, what do you say about that platti
 
#53 ·
So today I bled very often comes to 60 bar -61 bar but not always, it pumps for so long and you think you have 1000 bar but it stays at 60. bleed the clutch it works but bleed the actuator block when I start it, start pumping immediately should it not bleed first? So he immediately starts to pump when venting the actuator block and then always the message pressure not reached in the specified time. it seems to me as if he doesn't you bleed the actuator block he always talks about the pressure build-up. and the pressure memory test is good
Personal computer Computer Font Gadget Output device
 
#54 ·
Still the block has air, the way to help the block bleed is to manually shift gear with software for sometime and try again, or drive the car around with frequent gear shift, bring INPA with you in case pressure drop too low and have a gear stuck so tou need software to put gear to N and start the car and continue or drive back.
 
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