Repair Defender Sills, B-posts and C-posts, part 1: Removal

7304dfc0-4feb-4c40-8c37-5cffe5246db4

Latest Posts
07 July 2023
|
Removing the structure is the first task : credit: © Trevor Cuthbert
Long wheelbase station wagon side structures can rust severely. Trevor Cuthbert shows how to remove them for repair or replacement

Need to know

Time: 6 hours (to remove both sides)
Cost: No cost so far
Difficulty: 4 out of 5
Models: Defender 110 Station Wagon, 110 Double Cab, 130
Double Cab.
Tools needed: General workshop tools, trolley jack, drill, impact wrench, angle grinder.
Work safely:
• Disconnect the battery before work begins (earth lead first).
• Wear eye protection when drilling and working with flaking metal components.
• Wear tough gloves and eye and face protection when using an angle grinder. Be aware of how aggressively the grinder can twist and kick back in your hands.
• Wear safety boots and gloves.
Contacts: YRM Metal Solutions Ltd, Tel: 01388 488150, yrmit.co.uk.

 

Most utility Land Rovers and later Defenders suffer from rust issues in the steel main bulkhead and chassis. The 110 station wagon models have additional major steel structures that are also prone to expensive rust damage – the sill, B-post and C-post assembly on each side of the vehicle. The sill is a longer version of the single door sill found on two-door models; the B-post supports the roof. The second row doors are attached to the B-posts, while the C-posts complete the structure to the rear body, building strength into these long-wheelbase passenger carrying
Land Rovers.

The Defender 130 double cab pick-up trucks have a similar sill and B-post arrangement and can suffer rust damage in the same way as the 110 station wagons, albeit without the bother of C-post corrosion (the C-post here is essentially formed by the rear body bulkhead).

In previous issues of LRM we have seen how the B-posts and C-posts on station wagons can be rebuilt using repair panels and kits manufactured by YRM Metal Solutions. Now the company is producing complete sill assemblies, pre-formed with the B-post and C-post in standard steel or hot-dip galvanised steel. This means there are now three options to deal with rust in the bodyshells: repair the existing structure, replace with good second-hand units (if you can find them), or fit complete new sill assemblies.

To carry out the repair or replacement, the damaged areas need to be identified and cut away, or completely removed. With the vehicle shown here, it was decided to completely remove the structures and replace with new assemblies. The sills are normally bolted to the station wagon body crossmember, towards the rear of the vehicle, but here the sills were already unbolted because a new body crossmember had been recently fitted, with the sills next to be dealt with.

Starting at the C-post: The rivets holding the outer body skin to the steel C-posts are drilled out using a 5mm drill bit. Some of the lower rivets are corroded and broken.

De-panelled: The aluminium filler panel can now be withdrawn after all of the rivets holding it in place have been removed. It will be reusable on the finished job.

Horrors revealed: Behind the filler panel, the extent of the rust on the lower section of the C-post can be seen, and indeed the rust is taking hold of the sill below it, too.

Bolts may shear: This bracket on the inside of the C-post is removed with an impact wrench, while a 13mm spanner holds the nut underneath (may need to cut heads off).

Just hanging there: With bolts removed, the C-post almost fell off by itself, due to rust. Otherwise, the complete sill, B-post and C-post assembly can be removed in one piece.

Doors off: The second row (rear) door now needs to be taken off by removing the four hinge screws from the B-post using a Pozidrive #4 screwdriver (or impact driver).

Removing the furniture: Inside the Land Rover, the seatbelt needs to be removed at the top anchor point on the B-post, using a 17mm (or sometimes 18mm) socket wrench.

A tight spot: The headlining can be eased down just enough to get a 10mm spanner onto the nuts above, to unbolt the top of the B-post from the roof panel.

Content continues after advertisements

Small fixings: The lower rear of the B-post is held with two M8 bolts through this body plate into threaded holes, easily removed with a 10mm socket or spanner.

Unbolt or cut: The floor panels do not need to be completely removed, but the troublesome fixings at the sills need to come off in the front as well as the rear.

More cutting or drilling: The sill is held to the bottom of the bulkhead by a pair of bolts on a captive plate which almost always fractures, annoyingly allowing the bolts to spin.

Gravity does its thing: Now that all of the fixings have been removed, the sill and B-post assembly begins to drop on its own, and is ready to be pulled free from the vehicle.

Ease it outwards: The sill is pulled out slightly from under the seatbox and floor to lower it. The B-post was so rusted it broke off the sill at this stage.

Out on the floor: The sill has been successfully removed now and the fractured B-post is balanced on top to show how it might have looked if it hadn’t broken off.

Repairable? Close-up of the fractured B-post to sill joint shows how the strength of this vehicle is compromised. It would need a lot of work to repair this structure.

Better option: For this Defender, the owner has decided on fitting brand new galvanised sill, B-post, C-post assemblies for both sides, to build in longevity and peace of mind.

 

In part 2: Trevor fits the new galvanised sills, B-posts and C-posts to both sides of the vehicle. See how he gets on in our 'How to' section here.

 

LIKE TO READ MORE? Try our Budget Digital Subscription. You'll get access to over 7 years of Land Rover Monthly – that’s more than 100 issues plus the latest digital issue. The issues are fully searchable so you can easily find what you are looking for and what’s more it’s less than 10p a day to subscribe. Click here to find out more details and start enjoying all the benefits now.