Tweet
Recently the alternator hit the chassis when I changed direction, a good indication that the engine and gearbox mounts might need some attention. Unfortunately the alternator bearings were damaged due to this impact. I therefore ordered a new alternator (with the aim to rebuild the old one as a spare).
I then also changed the engine mounts & gearbox mounts. I used polyurethane from Duraflex (they sent the wrong bushes first time, but did swap them out after I sent them back for the right ones, did take a while before they responded to emails though so you're aware if you choose to get some of these). The original engine mounts were supplied by Marlin so I didn't have specific part references for them.
They are 35mm thick with M10 studs, the closest I could find were Land Rover Defender gearbox mounts. I ordered the ‘soft’ variant which is 70 shore. They had mounts for BMW gearboxes, went for the '80 shore a' ones which is the normal hardness option for the bush.
Land Rover gearbox mounts: https://www.duraflexpubushes.com/lan...9560-284-p.asp
BMW Gearbox mounts: https://www.duraflexpubushes.com/bmw...ting-257-p.asp
The engine is under much better control now, I get less oscillation / vibration into the front wings and feels better when driving.
I also had two worn out cracking ball joint boots so I changed those too.
Gearbox Mounts
Old BMW bushes compared to the new poly bushes. The new bushes are a bit chunkier (same height)
Here’s the gearbox mount cross member – had to take this all the way out to get the new bushes in place, a little bit fiddly.
After some swearing the new bushes are in place with the cross member bolted back in.
As the new bushes are more chunky than the old one ones I had to use the deathwheel to grind down this spanner to fit between the chassis and the bush to hold the bolts when doing up the nuts inside the car.
Engine Mounts
Removed the bonnet and both side panels for this job:
Jacked up the engine after undoing the lock nuts until there was enough clearance to get the old bush out.
A comparison between the now deformed bushes and the new poly bushes. The studs are a bit longer on the new one so the engine needs to be lifted a little higher to get the new bush in (on the passenger / intake side)
On the driver/exhaust side the steering column linkage is in the way of lifing the engine high enough to get the bush out. It was much easier to take the 4 bolts out that hold the engine mount to the block and pivot it out the way.
Here with the new bush fitted and bolted down:
Alternator Change
Big ol hole where the old alternator was removed, added a small notch in the chassis here to allow more clearance in future.
I got the new alternator from https://www.schmiedmann.com in Denmark, mostly because I needed a glow plug control module for my daily and they were the only people in Europe that had stock at the time! The new one is very shiny!
New alternator in place, added a new v-belt while I was at it as the old one wasn’t brilliant anymore.
Here’s the new alternator hiding away among intake and water pipes!
The really nice thing about the new alternator is that it charges straightaway after starting the engine. The old alternator needed you to rev up past 3000 rpm before it would start charging.
Ball Joints
These don’t last super long every few years I need to replace them, these were not damaged from dirt ingress yet so I was able to just change the boot (sourced from ebay ej-parts size 16/31/23). I did fit one new ball joint as I didn’t have enough time to wait for the boots to get it through the MOT this year so I was able to pick one up from Euro Car Part locally.
Yeahy rotten rubber (this is now an MOT failure, these might have squeaked through as they were not cracked all the way though, but it was time to change them):
One new ball joint fitted:
This ones pretty bad, but the ball part of the joint was still good.
New boot from ebay with the mounting hardware from the old boot
Reassembled, old ball joint with new boot:
Still to do are the differential bushes – the stock BMW M bush (from the Z3M) has a lot of movement, the centre mount hold is tearing out of the rubber. Additionally the ford TCA bushes used to mount the front of the diff to the chassis feel soft and are squeaking quite a lot. If you move the car by hand with a gear selected the diff does a nodding dog impression. I’ve got some poly bushes to install in the near future for that too.
I then also changed the engine mounts & gearbox mounts. I used polyurethane from Duraflex (they sent the wrong bushes first time, but did swap them out after I sent them back for the right ones, did take a while before they responded to emails though so you're aware if you choose to get some of these). The original engine mounts were supplied by Marlin so I didn't have specific part references for them.
They are 35mm thick with M10 studs, the closest I could find were Land Rover Defender gearbox mounts. I ordered the ‘soft’ variant which is 70 shore. They had mounts for BMW gearboxes, went for the '80 shore a' ones which is the normal hardness option for the bush.
Land Rover gearbox mounts: https://www.duraflexpubushes.com/lan...9560-284-p.asp
BMW Gearbox mounts: https://www.duraflexpubushes.com/bmw...ting-257-p.asp
The engine is under much better control now, I get less oscillation / vibration into the front wings and feels better when driving.
I also had two worn out cracking ball joint boots so I changed those too.
Gearbox Mounts
Old BMW bushes compared to the new poly bushes. The new bushes are a bit chunkier (same height)
Here’s the gearbox mount cross member – had to take this all the way out to get the new bushes in place, a little bit fiddly.
After some swearing the new bushes are in place with the cross member bolted back in.
As the new bushes are more chunky than the old one ones I had to use the deathwheel to grind down this spanner to fit between the chassis and the bush to hold the bolts when doing up the nuts inside the car.
Engine Mounts
Removed the bonnet and both side panels for this job:
Jacked up the engine after undoing the lock nuts until there was enough clearance to get the old bush out.
A comparison between the now deformed bushes and the new poly bushes. The studs are a bit longer on the new one so the engine needs to be lifted a little higher to get the new bush in (on the passenger / intake side)
On the driver/exhaust side the steering column linkage is in the way of lifing the engine high enough to get the bush out. It was much easier to take the 4 bolts out that hold the engine mount to the block and pivot it out the way.
Here with the new bush fitted and bolted down:
Alternator Change
Big ol hole where the old alternator was removed, added a small notch in the chassis here to allow more clearance in future.
I got the new alternator from https://www.schmiedmann.com in Denmark, mostly because I needed a glow plug control module for my daily and they were the only people in Europe that had stock at the time! The new one is very shiny!
New alternator in place, added a new v-belt while I was at it as the old one wasn’t brilliant anymore.
Here’s the new alternator hiding away among intake and water pipes!
The really nice thing about the new alternator is that it charges straightaway after starting the engine. The old alternator needed you to rev up past 3000 rpm before it would start charging.
Ball Joints
These don’t last super long every few years I need to replace them, these were not damaged from dirt ingress yet so I was able to just change the boot (sourced from ebay ej-parts size 16/31/23). I did fit one new ball joint as I didn’t have enough time to wait for the boots to get it through the MOT this year so I was able to pick one up from Euro Car Part locally.
Yeahy rotten rubber (this is now an MOT failure, these might have squeaked through as they were not cracked all the way though, but it was time to change them):
One new ball joint fitted:
This ones pretty bad, but the ball part of the joint was still good.
New boot from ebay with the mounting hardware from the old boot
Reassembled, old ball joint with new boot:
Still to do are the differential bushes – the stock BMW M bush (from the Z3M) has a lot of movement, the centre mount hold is tearing out of the rubber. Additionally the ford TCA bushes used to mount the front of the diff to the chassis feel soft and are squeaking quite a lot. If you move the car by hand with a gear selected the diff does a nodding dog impression. I’ve got some poly bushes to install in the near future for that too.