Corrosion on the bulkhead

Now that I had everything removed from the front end that wasn't welded in place, it was time to clean it up, remove all the oil, stonechip and grime that had accumulated over the last 20 years and see what metal needed replacing - I wasn't expecting much in the way of corrosion, as the good old A-series gives the engine bay a liberal coating of oil, which should have protected it from corrosion to a very large degree...

I wasn't too far wrong on the bulkhead, only some minor surface corrosion, but the picture right shows the upper engine steady mount as it looked when I'd removed the engine.

The top section of the upper engine steady bracket is part of a plate that sits under the brake and clutch master cylinders, which was in a terrible state, see the picture left - you can just make out that a washer has been welded over the corroded bolt hole at some point to repair it - quite common practice as far as I know, and not a problem as long as the rest of the plate is OK, but given the poor state of the plate, I'll be replacing this rather than arse about repairing a corroded and inexpensive part.

There is obviously a lot of something built up around the lower bracket - I thought the build up was going to be seam sealer or similar, but when I took a wire brush to it and removed all the paint, it turned out to be weld! (see left). Now I'm not the world's best welder by any stretch of the imagination, but that really looks like some pretty poor welding to me. On the one hand it hasn't broken (with the shell taking enough of a wallop to crack the bulkhead by the lower front subframe mounts), but on the other hand the person who did it obviously wasn't taking enough care about the job they did... You can also make out from the photo (look at the upper right) that the crossmember has been dented inwards - this could be due to the bump that cracked the lower subframe mount area, or just part of the generally poor job of fixing the upper engine steady to the crossmember, I can't really tell. I think this might well have been done as part of the engine swap (from 998 to 1275 MG Metro) - I think the small and big bore engines had different upper engine steady mounts. Coupled with the far too long machine screw that was holding the upper engine mount to the bulkhead (see the top photo), and it's clearly not the best attention to detail!
You can't quite make it out in the picture, but the top right section of the mount hasn't got any weld on it at all, and I can't figure out why someone would do that, as it seems very odd not to bother welding on the last section. My theory is that whoever did it was stitching the mount on section by section to avoid warping the crossmember, and forgot to come back and do the last section...

Next port of call was the bottom of the bulkhead, around the lower subframe mounts - I knew that I was going to find some problems here, as I'd already seem some cracks around the bolt hole area, but I needed to clear off all the old underseal and paint before I could be sure just what was needed. Taking advice from some very knowledgeable people on Pistonheads I had already decided to reinforce the area around the bolt holes by welding on some thicker sheet (16 guage recommended - about 1.6mm in new money), so I needed all cracks, holes and rust removed before I started that! So, twist cup wire brush back in the angle grinder, and I started on the inside of the bulkhead, revealing the factory reinforcement plates, which look a bit small to me - the offside one had already cracked (see left). I had to remove the existing plates to be able to insert some new (larger) plates, so I drilled out the spot welds, (including a few along the floor to bulkhead area, to allow for inserting larger plates into between the bulkhead and floor section) and prised the plates off with a prybar, leaving the nice rusty looking metal behind (right):

Fortunately a quick blast with the wire brush showed it was only surface rust, which was a relief - I really did not want to be replacing large sections of the bulkhead, with the associated difficulty in making sure the subframe bolt holes remained in the right place!

You can see from the photos above that there is a large crack in the bulkhead on the offside needing repair, there was also a crack on the nearside, which you can see in the photos below (offside on the left, nearside on the right) which were taken following cleaning up the outside of the bulkhead with the wire brush.

The messy hole in the middle of the left photo is due to me not being able to find the spot weld to drill out - there was a fair amount of surface pitting (no doubt contributing to the bulkhead cracking) and it was one area I couldn't see the spot weld clearly, so took a few attempts. That will be plated up with a small patch.

Moving back up to the scuttle, I decided to remove the windscreen to get a look at some rust I could see bubbling up underneath the paintwork.
This is quite an easy job - prise the filler strip out of the channel in the rubber with a scredriver (carefully so not to break it), then just gently push the windscreen out from the inside of the car, it'll pop right out of the rubber. Wearing goggles and thick gloves is a good idea, in case it shatters or cracks.
With the windscreen removed, I took the wire brush to some rust bubbles I could see around the windscreen seal:


Not quite what I was hoping to find, but it could have been a lot worse! Most of the rust seems to be concentrated in a few patches where the scuttle panel joins to the bulkhead, with the scuttle panel having done most of the rusting. There is only one really bad area where the seam joining the two has completely rusted away, but even so these will all require patches rather than wholesale panel replacement (luckily for my wallet).