Starter Motor
- Thread starter benben
- Start date
It's not your solenoid. Its the brushes being worn.
At some point one of them doesnt make good contact anymore (probably partly due to some dust) and it shuts out. A tap gets it going again.
Replace the brushes before a contact point on your commutator burns out (been there done that).
these are the brushes you need:
https://www.aliexpress.com/item/Electric-Starter-Carbon-Brushes-Holder-For-BMW-X5-X6-520-525-530-Starter-Motor-54-53mm/32645223102.html
It's a very common problem on these startermotors once they get 10years old or so.
At some point one of them doesnt make good contact anymore (probably partly due to some dust) and it shuts out. A tap gets it going again.
Replace the brushes before a contact point on your commutator burns out (been there done that).
these are the brushes you need:
https://www.aliexpress.com/item/Electric-Starter-Carbon-Brushes-Holder-For-BMW-X5-X6-520-525-530-Starter-Motor-54-53mm/32645223102.html
It's a very common problem on these startermotors once they get 10years old or so.
Yes you can clean it but it requires to remove the startermotor.
So first disconnect the battery, and you can take the startermotor out from the top.
First disconnect the leads going to the solenoid, and the startermotor sits in the engine block with inverse torx bolts (either e10 or e12)
I dont know how acessability is on the e89 though.
If you open it up it looks like this:
So typical carbon crud.
If you wait too long with replacing the brushes, you get this:
A burnt through collector platelet due to one of the brushes not making good contact.
So then you have to get a new (replacement) starter motor, which obviously also will have worn brushes unless you get a refurbished one.
If you choose for a refurbished one, you might get another type (for example m52) they all fit afaik but are different in size or parts.
To replace the brushes, you need to get the rear aluminium cap off. That is held in place with 2 long torx bolts that run to the side of the starter to the front. Use penetrating oil where the threads to into the housing. They usually are pretty stuck and the metal of those torx bolts is weaker than expected. You can also put some grip pliers on the stem of the bolt to aid in torque.
These bolts: (the ones that run alongside the housing):
After loosening the bolts, you can remove the screws in the cap. The brush-bridge is screwed in the cap:
To reassemble, first put the brush-bridge on the commutator. You can pull the brushes so far back in the bridge that the springs hook to the side of the brushes (so the brushes arent pushed back in again), slide it over the commutator, push the brushes back in, place the aluminium cap, screw the bridge to the cap (by aligning those holes) and put the trox bolts back in.
You can obviously also dismantle the complete starter to clean everything meticulously.
these are all the parts:
The only thing that is difficult to disassemble, is a small circlip that sits around the shaft and holds a small bushing in place. you need to remove that if you want the engagement gear (with its one way clutch) off the driveshaft. Its a pain to get that off.
So first disconnect the battery, and you can take the startermotor out from the top.
First disconnect the leads going to the solenoid, and the startermotor sits in the engine block with inverse torx bolts (either e10 or e12)
I dont know how acessability is on the e89 though.
If you open it up it looks like this:
So typical carbon crud.
If you wait too long with replacing the brushes, you get this:
A burnt through collector platelet due to one of the brushes not making good contact.
So then you have to get a new (replacement) starter motor, which obviously also will have worn brushes unless you get a refurbished one.
If you choose for a refurbished one, you might get another type (for example m52) they all fit afaik but are different in size or parts.
To replace the brushes, you need to get the rear aluminium cap off. That is held in place with 2 long torx bolts that run to the side of the starter to the front. Use penetrating oil where the threads to into the housing. They usually are pretty stuck and the metal of those torx bolts is weaker than expected. You can also put some grip pliers on the stem of the bolt to aid in torque.
These bolts: (the ones that run alongside the housing):
After loosening the bolts, you can remove the screws in the cap. The brush-bridge is screwed in the cap:
To reassemble, first put the brush-bridge on the commutator. You can pull the brushes so far back in the bridge that the springs hook to the side of the brushes (so the brushes arent pushed back in again), slide it over the commutator, push the brushes back in, place the aluminium cap, screw the bridge to the cap (by aligning those holes) and put the trox bolts back in.
You can obviously also dismantle the complete starter to clean everything meticulously.
these are all the parts:
The only thing that is difficult to disassemble, is a small circlip that sits around the shaft and holds a small bushing in place. you need to remove that if you want the engagement gear (with its one way clutch) off the driveshaft. Its a pain to get that off.
Remember that when you try to remove the starter motor, this is your best friend:
Magnet on a stick.
You're bound to drop one of the bolts that then of course ends up exactly between the sump and bottom tray and a magnet on a stick saves you a lot of time :lol:
Goes for a lot of jobs :roll:
Magnet on a stick.
You're bound to drop one of the bolts that then of course ends up exactly between the sump and bottom tray and a magnet on a stick saves you a lot of time :lol:
Goes for a lot of jobs :roll:
WOW, awesome reply guys, thanks for the time taken to do this. someone who knows how should make this into a sticky.
So I ordered a replacement starter motor, Im thinking of changing it instead of cleaning the existing one. Is that a big job to do from the top? I understand you disconnect the battery and remove the lids connectedto the solenoid, then there are two E10 or E12 torx thingiz, and then it just comes right off?
Cheapest mechanic i found quoted 185 dollars to do it so if i can avoid it, would be great.
So I ordered a replacement starter motor, Im thinking of changing it instead of cleaning the existing one. Is that a big job to do from the top? I understand you disconnect the battery and remove the lids connectedto the solenoid, then there are two E10 or E12 torx thingiz, and then it just comes right off?
Cheapest mechanic i found quoted 185 dollars to do it so if i can avoid it, would be great.
stevengude
Member
Mine packed up yesterday. Andy has replaced tonight, all working again now - very happy.
You also need to remove the air filter housing, but thats just a few bolts and a clamp.benben said:Is that a big job to do from the top? I understand you disconnect the battery and remove the lids connectedto the solenoid, then there are two E10 or E12 torx thingiz, and then it just comes right off?
Removal of starter
removal of air iintake housing