Brakes Rear Backplate

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HarryMann: The rear brakes on the T25 are self-adjusting single-leading shoe drum brakes.

The backplates are originally quite thick galvanised steel pressings (handed L/R). 
After 15 ~ 20 years they can rust through in places or rust-weld themselves to the bearing housing on which they are mounted 
This entry provides information, tips and techniques to help remove, refurb or replace them with new ones.
Syncros are identical to 2WDs and can deteriorate even faster of course 
N.B. The front disc splash plates are of similar construction and can rust in much the same way.

brickwerks kit

Some Fitting notes by Hacksawbob

Brickwerks supply a "Backplate kit" This includes the backplates, drums, shoes, dowels, handbrake cables, lower mounting pivot points, lower locating pivots, brake cylinders all in the region of £300 It also includes the springs cups and pins that are missing from budget offerings from other suppliers [1]

Here's what you need to know. The dowels don't come fitted. You will need to hammer them in or get them pressed in. It is awkward on a press without the right set up. The dowels have a chamfered end and a rounded end, general consensus is that it doesn't matter which way around they go. They should be flush on the inside of the lower pivot block though. It may be easier to fit the chamfered side into the backplate especially if you are hammering them in to get them straight. The kit doesn't come with the lower mounting M10X20mm bolts (X2 each side) , so you can reuse your own. If you are buying new you may need to source them from a specialist as they need to be 10.9 tensile strength or above. I fitted mine with 12.9 tensile strength hex cap socketed 30mm bolts and added some nuts the other side as belt and braces (also to keep the bolts clean the other side) however the bolts weren't long enough for the nylock bolts to engage so maybe 40mm might be better? If you decide to paint your back plates it may be an idea to mask off the dowel mounting poit and the handbrake cable holes as these are very tight fitting.

other items you might need

The kit doesn't come with hub nuts and split pins. If you are going to do this right (and after spending North of £300 you are the sort of person that likes to do it right!) The hub nut is a use once item, although people do re-use while you are ordering your brake parts you make think about replacing the hub nuts and slit pins for new. If you are fitting this kit you WILL need to remove the hub nut. you will need a 46mm socket and a big breaker bar, or a 46mm smackable hub nut remover by EMPI [2] about £11 from just kampers. These nuts are supposed to be done up to 500NM, a torque wrench for this would cost upwards of £300 so the smackable job works out cheap unless you can rent one! If you mark the hub nut and hub before you remove it, then count the number of turns before it comes free you will have a good idea of how much to put it on, so long as when you remove the wheel retaining part of the hub with the wheel bolts on it you don't move the wheel thereby changing the position of the starting thread (like I did!)Jed has a video on this here be very careful with the brake lines using this method, it is very easy to introduce kinks into the brake lines if you aren't!

Part Nos

To start with, these are the VW Part Nos: 251 609 425D backplate - Left (1) 251 609 426D backplate - Right (1)

You may also need the lower pivots (Mounting Insert for brake shoe - 4 off) - if you can't free up and remove them from the old backplates

251 609 209 (4)

and the plugs to bung the adjuster hole up are:- 113 609 163

Beaker says: As of 5th April, 2006 the price was: £51.03 plus vat from VW each, inserts(plugs) £3.67+ each

File:Backplate new.jpg

Simon Baxter: Well, for the price it's now worth arsing about with second hand.

HM: Yes, at £10/hour, Simon's right, must have spent 3-4 hours at least refurbing just one, but its back on and looks good, but still not new... depends how much dosh you can spare and how long you can wait to get them (a week minimum usually)

Don't forget to get a new set of springs and bits and pieces (GSF, about £10) and make a good job refurbing the auto-adjuster bar. Use castrol PH zinc based grease on pivots and rubbing points. GSF do new drums and shoes at a good price if VW scare you off.

AndySimpson: Original VW riveted shoes are much better than the aftermarket bonded-ones. (Highly likely - general opinion is that aftermarket brake parts vary from Not as good as OEM to shocking!)


Some of these backplates are getting as thin as paper by now, others will be relatively easy to remove. So Rbest read the whole text before starting the job!

Strip the shoes and springs off;

Try to remove the handbrake cable from its steel sleeve in the backplate. These normally seize badly, so a brush up, some pen oil and then gripping on the larger diameter plastic sleeve at the back with a pair of large wide jawed pliers or grips , start to twist it back and forth until you can also start pulling it out a bit. Either remove completely if possible or then leave it until the backplate is right off.

Clamp the brake hose carefully, rremove the hydralic connection to the slave cylinder, undo the single bolt holding it on and remove it, by scraping off any rust around its edge and twisting if necessary to free it up;

Heavily wire brush and pen oil the area behind the plate where the two M10 bolts and the central dowel are located (at the bottom pivot). Undo the two 17mm bolts at the bottom;

Inspect the edge of the large central hole where it fits over the bearing housing and the behind it where it sits against the bearing housing mating face... to how badly it is rusted on; scrape around the edges front and backwith the flat of a screwdriver to remove any deep rust scale before trying to remove the whole backplate;

Alternately, try tapping the sides from behind, adjacent to the bearing housing and then with a fairly stout punch, start to drive the dowel pin between the bolt-holes from the back, under the housing;

Repeat the above loosening procedure, looking for where it has freed up and come away from the housing and where it hasn't. You may have to strike the dowel fair and square the first time to initially loosen it, but don't keep driving this until the backplate has broken its seal and come away. Keep pulling gently and tapping from behind at the top;

Remove the handbrake cable sleeve from the backplate uisng a twisting action. the palstic sleeve often takes quite a bit of punishment but can be fettled up before refitting the backplate;

Inspect the backplate for damage and decide if good, bad or ugly... The first two can be repaired, and refurbed. if it is holed here and there but substantially sound, a MIG welder can fill them in and sometimes rebuild small sections with beads of weld or in extremis, weld steel patches in, but not in keyareas that mate with shoes, springs or the bearing housing at the back.

File:Backplate Welded.jpg

Refurbing (and MIG welding up holes)

Here's a bad one I MIG'd up in a lot of places, the whole thing around the boss was full of pinholes, and I strengthened it across the top spring hanger, and around the edges here and there where I thought it's stiffness had been compromised. MIG on low or even lowest setting and build a bead bit by bit around the holes, before then filling them in. Grind off carefully where necessary (I used a Rotozip with see-thru flexdisc).

Remember that the braking loads don't go through the backplate, they're taken straight out by the wheel bearing hub casting at the top cylinder and bottom pivots. Thus the backplate only really acts in a supporting and positioning role. As long as it's still square and true, not too flexible, and basically waterproof from behind (plug the adjuster holes with bungs), then it should do the job OK. The flat mating face of the bearing housing supports it quite well.

A lot of the welding up was to fill holes and not for strength, but where it mates to the casting face, any welds need to be ground reasonably flush, or don't even bother welding them up. IMO it could even be stiffened up sufficiently by pop-rivetting nicely made plates on the back of it if necessary and care taken not to foul the housing or any moving parts, but doubt MOT testers would agree.

Here are my efforts, after a quick few thin coats of Weld-thru zinc primer. About an hour or so 'chipping' heavy rust flakes off, using a bearing scraper in those deep rim pressings General Engineering Scrapers, just perfict! Clamp it down to a bench first and wear gogs... File:Backplate Refurbed.jpg

Quite a bit of MIGing, but the outer rims weren't totally rusted through, if they're really bad you'd need to be quite devoted to repair the whole thing, and better than me at welding too. Brazing would be a good option here, if you have gas. (MOT testers would fail a backplate with the rims rusted through, as not only do they provide a lot of stiffness, but prevent water ingress.

Clean threads and free-up push/adjusting rod (auto adjuster rod/star adjuster), to give a freely spinning ratchet wheel and then fill tube with PH grease and lightly lubricate threads. NB. These threads are handed, the right-hand-side having a left-hand thread. {Copper-slip is often used as a substitute for Castrol PH lime-based grease}

File:Push adjusting rod.jpg