This is on the back of another recent thread that prompted me to get the old starter for the MK2 out of storage. Did it just for the sake of it and as it didn't work there was nothing to lose. All very doable, if a little involved and no special tools are needed. I didn't replace any servicible parts, even though quite a few of them are still readily available. If I could've been arsed, should really have changed out the 4 x bushes while I was in there, they're more worn than not, but some soldering's required, plus was too impatient to order / wait for them to arrive... maybe for again, no biggy getting at them, you just by take off the end cap This starter was just bunged up really, old grease and (lots of) carbon from the bushes had coated the insides plus there was evidence of some very minor water ingress. Good clean and a re-grease and it's running like a sewing machine again. You wouldn't need to go as far as I did, it was just curiosity made me strip it right down to the bare bones, including taking the magnets out which wasn't strictly speaking necessary, but interesting. Three pairs of hands needed to get it all back together, hence the new paint work already looking a bit worn. The peg I've arrowed and the corresponding slot in the aluminium end cap... one to be aware of, they need to line up exactly, easier said than done.
Think I've found this available as a complete 'holder', so saves on soldering in individual brushes. Info's not all that clear though and quite conflicting in places, so will have to wait and see if it's what I'm after when it arrives. Bosch appear to still do them but are proving elusive in the UK, so the one I've ordered is instead an aftermarket brand. Just speculating that worn brushes are likely the primary cause of starter issues, they're sacrificial and intended to wear down after all. Despite the amount of material you see in the image, most of it's contained within the holding part (not pictured) and doesn't reach the contact surface. If changing them is just going to be a case of slotting in a complete new unit it should make this particular repair simplicity (and cheap) so well worth trying before splashing out on a replacement starter... watch this space.
Nice job. I've got a starter where the front bearing thingy is completely gone, axle is able to move around, sparks flying everywhere. I also disassembled it and put it back, but didn't look for spare parts yet. Are they available?
So far, for this particular starter 0 001 114 005 / 055 911 023 M, have found the service parts marked in red. May be that they're interchangable with others, but would need Bosch numbers to try and confirm that. Did see a press in bush service kit too (yellow arrows) which is maybe what you're referring to / need? Sods law, but can't find that again at the moment, but will eventually turn it up.
Seeing as you are sticking with the original don't forget to check/swap the brass bush in the bellhousing.
Good advice... potentially something that can easily get over looked. Could even be worth checking, even you're not changing out the starter, if it's been in there a long time. Got this cheapie motorcycle bearing remover years ago, just for the job and pulled it out like butter. Versions of it seems to still be generally available, and since used it for a few other small jobs, so it's paid for itself.
When I last changed my MK2 style starter there was little life in it when I turned the key. After I removed it the reason was clear. The end bearing had failed and there was plenty of lateral movement in the "axle". I replaced with MK3 starter which does away with the need for the bellhousing bearing.
MK3 starter does seem to be the way to go. The copper bearing for MK2 ones must become brittle with age, the one I replaced looked solid enough while in the bell housing, but came out in a couple of broken bits, even with the right tool.
So... to the replacement (aftermarket) holder / brushes which've turned up and it's confirmed are correct to this particular starter. A few different brands making them, plenty in the EU, but a lot of them aren't available in the UK that I could find. Bit of a hobsons choice then and this is the one I got for no other reason that it could be posted to me - AS-PL SBH0012 but prices vary quite a bit, at time of writing this was the cheapest. https://www.ebay.co.uk/itm/204386235476 Seems to be good quality and a nice touch was the small tubular affair you can maybe see in some of the images, just a transit piece to hold the brushes in place, but also greatly helped sliding them over the end of the shaft too. I'd to cable tie the originals to get them back in, not difficult, but fiddley. Something like the inner of a small cellotape roll would probably do the trick too. Word to the wise - if you're bench testing your work, get a half decent set of jump leads. The one's I initially used had been kicking about the garage for years, a bit on the thin side, so reckon they're probably 16mm2 cable and just not up to the job, will over heat and struggle to turn the starter after the initial attempt... could fool you into thinking there was an issue when there's not. Since got some nice 35mm2 ones and the starters just fly now.