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ZS rust patch welding turning into a mini-restoration

8.1K views 14 replies 9 participants last post by  nOw2  
#1 ·
So I found a rust hole on my ZS a couple of weeks ago.

This week I had it checked out for welding at a local garage. The conversation started with “do you realise how bad it is” ... :-/

After some poking the rot went around the inner wing and behind the front suspension.

It is fixable, it’s only metal after all. But it’s turned into a major job. The mechanic says that the subframe will need to come off to do the welding, plus steering rack, exhaust, etc. - first question is, would we on the forum agree that’s true (from the pictures)? He’s made it clear that he expects bolts to snap and it to become a tricky job.

The estimated cost is several times more than what I was offered on the car in trade-in four years ago! If this was any other car it’d be on the way to the scrapper! But I’m pushing ahead with it.

At the moment, this is the only problem area. The rest looks solid but there is plenty of surface rust.

So since much of the front is coming apart, I’m looking to replace as many parts as is sensible to do and do a mini-restoration job. I’ve asked the guy to strip as much rust as possible while it’s accessible and re-paint and re-seal the underneath.

I’m also intending to give him some new parts to fit - anything that looks bad, or anything that would be expected to be bad after 14 years. My shopping list looks like this so far:

  • Every nut and bolt in the anti-roll bar, steering rack and to re-attach the subframe.
  • New ARB, 24mm. Current one has surface rust.
  • ARB mounting brackets.
  • ARB bushes.
  • Lower arm bushes.
  • Radius rod bushes.
  • Lower ball joint.

I’m not looking to replace the suspension arms as they look rusty but solid. I’ll try to clean those up, repaint and refit.

I’ve had difficulty finding some basic parts - like the castle nut for the lower suspension ball joint RYH100420. I’m sure these are available elsewhere if I knew the size/thread type, but I can’t find that information!

Mostly I’d like everything from here:
https://rimmerbros.com/Item--i-GRID003093
https://rimmerbros.com/Item--i-GRID003096
https://rimmerbros.com/Item--i-GRID003097
https://rimmerbros.com/Item--i-GRID003690

So this is a general call for help - what’s worth doing now, what should I be doing? My budget is not unlimited but I’m willing to spend enough to get my car back up to standard.


Pictures of the rot:

ZS work, July 2018 by tkgbbs, on Flickr

ZS work, July 2018 by tkgbbs, on Flickr
 
#4 ·
Doesn't look too bad to me, but then my restoration thread will show you what I am dealing with lol

Sounds to me like your man is pricing himself out of the job, just because he doesn't want it or fancy it, which is fine it's his decision.

One 'L' shaped plate around the corner (after cutting back to good solid Steel) and that will all be fine for many years to come.

Access might be an issue on the face behind the steering rack though, bit difficult to tell from the photos. But if you can get the torch of a MIG welder in there, jobs a doddle.
 
#5 ·
Doesn't look too bad to me, but then my restoration thread will show you what I am dealing with lol

Sounds to me like your man is pricing himself out of the job, just because he doesn't want it or fancy it, which is fine it's his decision.
He did say he'd prefer not to do it - the welding is no big problem for him, but he thinks the subframe needs dropping for access which is where the trouble starts. He's been good to us so far so I don't believe he's try to mislead.

I want to do a mini-resto but would prefer to do that myself in my own time - welding is the only thing I can't do so I have to trust others.

I might shop around for a second opinion... just to be sure.
 
#6 ·
How DIY capable are you? Most of the garage cost will be labour to remove and refit parts. If you can do that on your drive and find a mobile welder to come out to you to repair it in situ then you'll find the price tumbles allowing you to splash more on the new bits ;)
 
#7 ·
" the castle nut for the lower suspension ball joint RYH100420. I’m sure these are available elsewhere if I knew the size/thread type, but I can’t find that information!"
I think they are M12x1.25.
I have used a Land Rover nylock nut in the past ( many of the pattern ball joints use nylock nuts). I will need to go through by nuts & bolts box tomorrow for part number.
 
#8 ·
Just recently wire brushed and scraped my nearside jacking point (plus surrounding area) and rust treated then undersealed.

It pays to sort it before it progresses too far.

Make sure you deal with all that surface rust ASAP, it's cheap, doable yourself, and will prevent any larger welding repairs later.
 
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#9 ·
Update - the car, and a big box of parts, have gone to the garage for the work to be done. Having a mini-restoration done, as initially planned.

I've even sourced and included a brand new subframe... "in for a penny" and all that.

I can do most of the basic mechanicing myself so it was tempting to put it on stands and get a mobile welder in once I'd stripped it (I even know a guy) but a rapidly approaching MOT co-inciding with a 2 week holiday put paid to that.
 
#10 ·
She's back home with 12 months MoT - no advisories!

The perforated bulkhead has been welded up, all surface rust cleaned and the underneath repainted and undersealed. Plus all the new components.

However - a P0131 code popped up and it needs a new bank 1 O2 sensor. This sensor wasn't removed but it looks like it was on the edge and failed when the exhaust was unbolted the get the subframe off. Always something, these days..
 
#12 ·
The wires seem okay, with conductivity at least as far as I can measure, and the front bank sensor shouldn't have been unplugged. My best diagnostic to order a replacement was that when unplugging, the code for "O2 sensor heater, bank 1 sensor 1" came up - so it's at least partially working.

I'm hoping the other oddity is just down to the sensor too: the car severely lacks power from cold at low revs - which I believe is a symptom of the O2 sensor fault causing a rich mix. Once warmed up or just at speed, it seems to push as hard as ever.

I've risked 30 miles in so far, and even though the bushes taken off were all found to be in fairly good condition, the car does seem to have that slightly more taught feel of a newer car. This gives me some impetus to do the same for the rear suspension - the ARB bushes on the back are definitely cracked, though there isn't any movement.

One other observation while it's on my mind: the quality of pattern parts. For this job, I bought new radius rod bushes for both sides, with the LH being available as OEM but the RH only as a pattern part. I didn't worry too much and expected the pattern part to be basically the same thing - but as my mechanic pointed out, the pattern part was made with steel less than half the thickness of the original. Side-by-side the difference looked huge. So we've left the old part on - it was in good condition anyway.
 
#13 ·
A new O2 sensor has been fitted, and the car's back to full health!

Thanks to DMGRS (again) and my local tame mechanic. I tried to fit it myself, but could not remove the sensor - so before I rounded it off, I popped the car down to the guy who did the welding who had it all done in 15 minutes.

Everything is finished, the car is perfect. So I've ordered some braided brake lines... just can't leave it alone.
 
#14 ·
Wow, I really feel for you. I just found the same on mine last week. It stated with a driver's seat mount snapping so I thought I should check for any other rot, being 3 weeks away from MOT. I found the same as yours on the drivers side, enough on the passenger side to warrant similar repairs although it's not through yet, and a rotten sill. managed to get a reasonable 'estimate' for repairs from a professional classic restorer (he doesn't do quotes, as he doesn't know the extent of work until he gets it apart, but it is a guy I trust). Hope to do the seat mounts myself.
 
#15 ·
Happy to hear you're getting it fixed. It'd be too easy to write it off at the first welding like this - sills are usually quick and easy but the problem with this location is that it needs other bits removed for access.

My ZS has a few hundred miles on it since the work and I have enjoyed every mile. Well worth it.