Hi guys, I'm looking to treat the underneath of my 323 and there's two questions I could do with some expertise with!

I was under there today with wire wool cleaning up any rust patches and road dirt/mud I could see, and there was quite a lot of gunk all over the spare wheel well. Now after going at this for a couple of minutes I thought to myself.... is this road gunk or is this actually some kind of sealant?! It feels kind of gummy? Am I making a mistake in sanding this back to bare metal or is this just what 10 years of road gunk looks like! Did they come from the factory with any sealant/treatment at all?

My second question is where is safe to put a trolley jack to get the car up on jack stands? At the back of the car I couldn't see anywhere obvious other than the centre of the crossmember, but I've heard that might not be a good idea?!

Any help is greatly appreciated!

Are you meaning only underneath the car, or inside?

The BA came with a grey, slightly spongy anti-corrosion layer sprayed across the bottom of the car, might be same on the BJ? (BJ owners please step in here! )

Or, just a thought, did a previous owner put waxoil or something similar in the areas you've found the gunky stuff?

While I can't speak for the BJ, the BA has a white sealant along a number of seams inside the boot and elsewhere; it looks a bit like the white waterproof grouting you use to seal around the edges of baths or sinks. It can feel a bit sticky. To be honest it is a pain, as it masks the start of rust coming up along the seams underneath, although I don't remove it unless I need to. So if the BJ has that stuff along interior seams, and it's still flat, that's fine; if you feel lumps in or under it, there's probably something underneath you need to deal with

I'll leave jacking points to a BJ owner, although I can't imagine that the side ones are that different to a BA (outer rails on either side, fore and aft, marked by two lumps in the metal, a couple of inches apart; jacking point is those couple of inches in between).

S

The centre of the crossmember would be fine for jacking.. just look where the jack will fit/sit tight and will not slip from the car.. after all the weight of the body is held on the "shoulders" of the crossmember soo it's pretty strong spot.

slightly spongy sounds about right, it seems to be around the spare wheel pan and also in the wheel arches, if that's the case I may just focus on problem areas rather than doing the entire bottom of the car!
I don't think they have waxoyled it, if anything it looks like its the one area of the car thats been neglected.

I found the jacking points along the sills but as there is a ridge along it (that fits nicely into the mazda jack but not into the cup of my trolley jack and axle stands) I could make a groove in a piece of wood them it I suppose? Also I'm don't think I've got enough space on the jack points at the back to get the stands in once it's jacked up