SMG Pump Rebuild DIY

[jayjaya29]

The accumulator is also gas charged. If you remove the accumulator, the rest of the pump body would be okay.

[ryanmkincaid]

Great write up on the SMG pump rebuild. Had I come across your post I may have kept my SMG pump instead of converting my M3 to a full manual. I have a question regarding the part; am I allowed to carry an SMG pump on an aircraft? I know you can't carry shocks on a flight cause they have gas compression. Is the same with the SMG pump?

Stupid question maybe.

[AvusBlueAus]

Has anyone done a rebuild with a mlr eng seal kit. I've pulled apart my unit and will reassemble it over the next few days but I can't figure out what the two circled orings are for.

I'm assuming the larger black one is for the pressure accumulator based on the size?

[eacmen]

It is actually 80 Bar 1160.3 psi.
That is max pressure and yes, it uses that kind of presure to perform shifting

Correct.

From the SMG technical concepts of operation doc:

[rossurf23]

It is actually 80 Bar 1160.3 psi.
That is max pressure and yes, it uses that kind of presure to perform shifting

[sapote]

To Oceansize:

I’ve read a BMW SMG 2 training course which states that the system max pressure is 80 bar and that once it reaches that pressure, the pressure relief valve/non return valve will bleed off pressure to preserve the system from over pressure and damage. So 80 bar is not the intended normal running pressure.

80bar is over 1000 psi, so I think you meant 80 psi.

[trigtm]

One thing this rebuild doesn't cover are two small aluminum washers that are between the inner pump housing (the gear casing) and the larger aluminum block. I had two and trying to trace exactly where they were as I wasn't expecting them when removing the gear casing. I believe they go between the gear casing and the larger alum block on the bolts that hold the gear casing down however they appear to be crush washers and had quite a bit of distortion when removed.

[rossurf23]

The new temp sensor is in the block. The original sensor is plugged into the harness and hanging in the engine bay. It’s been working perfectly since. Keep in mind I did all the other repairs. But as I did them in stages (first the Salmon Relay and temp sensor, then pump electric motor rebuild, then accumulator, then hydraulic pump seals and pressure relief/ non return valve), I can say that none improved the system or fixed the issue. The thing that convinced me it’s heat from the engine affecting the SMG oil temp was that it would act up after extended idle, in neutral with no shifting. Eventually, it would turn on the cog light and flag code P1717.
Have driven some 200 plus miles, no cog light or shifting issues. If anything the SMG oil temp is running at a higher level than designed but I don’t see any symptoms.
I guess the “correct” solution would be to relocate this unit to “drug compartment” , or to build some kind of SMG oil cooling system with stand alone cooler, pump and lines.
I am currently working on a design.

[jayjaya29]

I did replace the Salmon relay. I mentioned that in my post. Lol.
No biggie.
I like to report that I got my SMG working correctly .
I plugged my original temperature sensor into the harness and tie strapped so that the probe end is in the air.
Noticed at extended idle, the “oil temp” is 70C.
The pump cycles on every minute and a half or so and builds up to 75 bar in 5 tp 6 seconds.
After driving the car hard in Sport mode, DSC off and Shift setting to level 6, the car shifted hard and quick on every attempt.
After driving hard for and hour and idling for an hour, the SMG kept performing flawlessly, with no Cog light or or MIL light on.
Drove again this evening, performed some launches and shifting at 8k rpm, with DSC on and off and in Sport, normal, automatic and manual modes. Again, no issues!!

Since the Smg Oil temp was climbing so high at idle and in Neutral before, and consequently running the pump every 35-40 seconds, my conclusion is that the sensor was picking up engine heat as it is very close to the block and not actually reporting smg oil temp, but rather a combination of engine and smg oil temp. The SMG module is then making the pump run often to try and cool the oil, but upon failing to drop the temp, it defaults to N and flashes cog light and Mil.

So your solution was to take the temperature sensor out of the pump block and just let it hang out in the engine bay?

[rossurf23]

To Oceansize:

About SMG Pump Rebuild DIY
I have read other SMG Owners with good SmG systems report their systems build 72 to 75 psi in 5-7 seconds when hot. I’ve read a BMW SMG 2 training course which states that the system max pressure is 80 bar and that once it reaches that pressure, the pressure relief valve/non return valve will bleed off pressure to preserve the system from over pressure and damage. So 80 bar is not the intended normal running pressure.
You seem to have relocated your system which may cause the oil to run cooler.
I ended up installing my original temp sensor to the harness, secured it so that the probe is in the air and my system is flawless. Pump runs every minute and a half and builds to 78 bar in 5-6 seconds. Shifts great in all modes and driving styles and launches correctly.

[rossurf23]

I did replace the Salmon relay. I mentioned that in my post. Lol.
No biggie.
I like to report that I got my SMG working correctly .
I plugged my original temperature sensor into the harness and tie strapped so that the probe end is in the air.
Noticed at extended idle, the “oil temp” is 70C.
The pump cycles on every minute and a half or so and builds up to 75 bar in 5 tp 6 seconds.
After driving the car hard in Sport mode, DSC off and Shift setting to level 6, the car shifted hard and quick on every attempt.
After driving hard for and hour and idling for an hour, the SMG kept performing flawlessly, with no Cog light or or MIL light on.
Drove again this evening, performed some launches and shifting at 8k rpm, with DSC on and off and in Sport, normal, automatic and manual modes. Again, no issues!!

Since the Smg Oil temp was climbing so high at idle and in Neutral before, and consequently running the pump every 35-40 seconds, my conclusion is that the sensor was picking up engine heat as it is very close to the block and not actually reporting smg oil temp, but rather a combination of engine and smg oil temp. The SMG module is then making the pump run often to try and cool the oil, but upon failing to drop the temp, it defaults to N and flashes cog light and Mil.

[snaponbob]

Hello. Thanks for the most comprehensive SMG rebuild guide. The best I've seen. I have an ongoing issue with my 2003 E46 M3 SMG.
To give you a little background on myself, I am a Ford and ASE Senior master tech with 38 years' experience. Have worked at BMW dealer back when the E46 M3s were new between 2002 and 2006.
Back then under warranty, we would replace complete SMG pump units if we had any issues with SMG P1717 code.
I Keep getting code P1717 for on period. When hot Drops into N
Live data shows when cold, SMG relay and pump runs 5-6 seconds and builds up to 75 bar and holds for 2 minutes 30 seconds, when pressure drops to 52 bar, the pump runs again for 5 seconds and so on.
Once hot, with oil temp at 80 C, the pump runs for 7 seconds, builds up to 75 bar, but only holds pressure for 36 to 40 seconds, and when pressure drops to 56 bar, the pump comes back on. Accumulator checks ok, dropping off pressure at 39 bar.
All this after having replaced Salmon relay, temp sensor, sending out electric motor to Eurton and having it rewound and had new bearings and brushes installed. Also, I replaced
the accumulator, and lastly replaced pump seals and pressure relief/ non return valve.
The recommended Viton o ring kit did not have the correct solenoid o rings. But after having a hard time pulling off one solenoid and inspecting the o rings, I concluded that they may be ok and not my issue. I ordered a set from eBay and will retest.

So, the last bit of work was the SMG pump seal replacement. And there has been no improvement after any of the repairs attempted.
I am thinking my issue is due to engine bay temp causing internal leakage somewhere in the pump, solenoid seal area or even in a solenoid?

Other than replacing the solenoid seals, which I will do once I get them, can you think of what I could do to further diagnose this issue?
Is the pump run time for 7 seconds, every 30 to 40 seconds when hot normal? Seems to me it that is too often?

I have been tempted to plug my original oil temp sensor to the harness and tie strap to harness to see if that will make any difference.

Anyway, any ideas on what to do will be greatly appreciated. I am determined to fix this!

Have you replaced the salmon relay?

Another thing ---- you really should use a BMW capable scan tool to pull BMS specific codes. Generic OBD2 codes are NOT specific enough. (Ask me how I know !!)

[jayjaya29]

Been battling this issue myself, I'm gonna try the Burkhart fluid but according to this thread, changing out the pump itself solved the issue:

https://www.m5board.com/threads/smg-pressure-building-issue-when-hot-2009-m5-e60-smg.614981/page-2

[oceansize]

Hello. Thanks for the most comprehensive SMG rebuild guide. The best I've seen. I have an ongoing issue with my 2003 E46 M3 SMG.
To give you a little background on myself, I am a Ford and ASE Senior master tech with 38 years' experience. Have worked at BMW dealer back when the E46 M3s were new between 2002 and 2006.
Back then under warranty, we would replace complete SMG pump units if we had any issues with SMG P1717 code.
I Keep getting code P1717 for on period. When hot Drops into N
Live data shows when cold, SMG relay and pump runs 5-6 seconds and builds up to 75 bar and holds for 2 minutes 30 seconds, when pressure drops to 52 bar, the pump runs again for 5 seconds and so on.
Once hot, with oil temp at 80 C, the pump runs for 7 seconds, builds up to 75 bar, but only holds pressure for 36 to 40 seconds, and when pressure drops to 56 bar, the pump comes back on. Accumulator checks ok, dropping off pressure at 39 bar.
All this after having replaced Salmon relay, temp sensor, sending out electric motor to Eurton and having it rewound and had new bearings and brushes installed. Also, I replaced
the accumulator, and lastly replaced pump seals and pressure relief/ non return valve.
The recommended Viton o ring kit did not have the correct solenoid o rings. But after having a hard time pulling off one solenoid and inspecting the o rings, I concluded that they may be ok and not my issue. I ordered a set from eBay and will retest.

So, the last bit of work was the SMG pump seal replacement. And there has been no improvement after any of the repairs attempted.
I am thinking my issue is due to engine bay temp causing internal leakage somewhere in the pump, solenoid seal area or even in a solenoid?

Other than replacing the solenoid seals, which I will do once I get them, can you think of what I could do to further diagnose this issue?
Is the pump run time for 7 seconds, every 30 to 40 seconds when hot normal? Seems to me it that is too often?

I have been tempted to plug my original oil temp sensor to the harness and tie strap to harness to see if that will make any difference.

Anyway, any ideas on what to do will be greatly appreciated. I am determined to fix this!

Pump should build to 80 bar, not 75. Running for seven seconds is too long, mine has bursts of just a few seconds. Looks as though seals are bad or the accumulator but you said you tested the accumulator. Could also be your motor, while rebuilt, is not functioning properly and therefore won't build pressure fast enough which results in overheating. My system will hold pressure for four to five minutes at idle before it needs to build pressure again.

[rossurf23]

Hello. Thanks for the most comprehensive SMG rebuild guide. The best I've seen. I have an ongoing issue with my 2003 E46 M3 SMG.
To give you a little background on myself, I am a Ford and ASE Senior master tech with 38 years' experience. Have worked at BMW dealer back when the E46 M3s were new between 2002 and 2006.
Back then under warranty, we would replace complete SMG pump units if we had any issues with SMG P1717 code.
I Keep getting code P1717 for on period. When hot Drops into N
Live data shows when cold, SMG relay and pump runs 5-6 seconds and builds up to 75 bar and holds for 2 minutes 30 seconds, when pressure drops to 52 bar, the pump runs again for 5 seconds and so on.
Once hot, with oil temp at 80 C, the pump runs for 7 seconds, builds up to 75 bar, but only holds pressure for 36 to 40 seconds, and when pressure drops to 56 bar, the pump comes back on. Accumulator checks ok, dropping off pressure at 39 bar.
All this after having replaced Salmon relay, temp sensor, sending out electric motor to Eurton and having it rewound and had new bearings and brushes installed. Also, I replaced
the accumulator, and lastly replaced pump seals and pressure relief/ non return valve.
The recommended Viton o ring kit did not have the correct solenoid o rings. But after having a hard time pulling off one solenoid and inspecting the o rings, I concluded that they may be ok and not my issue. I ordered a set from eBay and will retest.

So, the last bit of work was the SMG pump seal replacement. And there has been no improvement after any of the repairs attempted.
I am thinking my issue is due to engine bay temp causing internal leakage somewhere in the pump, solenoid seal area or even in a solenoid?

Other than replacing the solenoid seals, which I will do once I get them, can you think of what I could do to further diagnose this issue?
Is the pump run time for 7 seconds, every 30 to 40 seconds when hot normal? Seems to me it that is too often?

I have been tempted to plug my original oil temp sensor to the harness and tie strap to harness to see if that will make any difference.

Anyway, any ideas on what to do will be greatly appreciated. I am determined to fix this!