1990 Mazda Miata MX5 - service

No advice about getting the shock out?

Anyway small progress today, first I though it was about time I sorted out the front of the garage a bit as I was falling over things,

before



after



doesn't look much but I now have somewhere to lay things out and a bit more space.

Had a look at a rear caliper, think I need a new cylinder (the dust cap is missing which may be a cause), was trying for ages to get the cylinder out with a foot pump etc, then read the manual and wound it out with the adjuster...



Tying electrolysis rust removal on the discs



No more progress, apart from cleaning and painting, until I work out what to do with the shock and get some parts.

Thanks for the info, although when I put my finger in the wishbone I can't feel a captive nut, more investigation needed and a session with the grinder.

Captive nut, is no longer captive and is now off the car!

Thanks for the advice here and the links, I managed to get a 17mm open ended spanner on the nut and get the bolt out.

Of course still have to release the top mount bolts, I think they have thread lock on them but can't use any heat as too close to fuel lines.

Meanwhile fun with electrolysis continues, one rear disc cleaned up and now trying to get rust off caliper piston.


Been distracted doing gardening, which did involve some stump pulling (OK a small shrub but lots of roots) with the Discovery :-)

Using a 14mm socket it doesn't hold and can't get a spanner in there, there looks to be traces of thread lock on the thread I can see. These are the top mount bolts not the shock absorber nut, which I've removed.

I've been experimenting with different forms of rust removal, Electrolysis and now Citric Acid after seeing others reports.

These are rear discs after sessions of electrolysis, kurust on the rear sides, the front side will have hammerite in the centres (not the wheel facing side. Carriers where cleaned up with a wire wheel. See earlier posts to get an idea of the state of the discs before.



Citric Acid bath, just starting off (yesterday at 7pm), 500g dumped into hot water found an old cat litter tray in the garden, part of a disposable glove stuffed in brake hose connection to stop 'acid' getting inside caliper..




and 9am today, getting there.


Meanwhile this is the top mount nut that is proving an issue, basically I'm grinding it down using a mini drill (tedious)!

I feel that I should be listening to Spandau Ballet Gold on loop while doing these jobs (or Gold from the soundtrack to 'Paint your wagon' a favourite film of mine except the bit when Clint Eastwood sings).

 

Brake bits have been painted with Gold Hammerite and it's time to finally fit the rear Gaz Gold coil-overs I bought 2 years ago!

But lets back up a bit, after a soak in Citric acid the rear calipers looked like this;



A bit of additional work with a wire brush



Next job was to sort out the pistons, the rear caliper pistons have a handbrake adjuster press fitted inside the piston. I tried all sorts of ways of trying to remove it before resorting to google (which is what I should have done before). After finding some forum posts about it, removed the piston seal and put piston back in caliper and put mole grips on piston to stop it moving and wound it out using the adjuster. Worked great except for chewing up the plastic adjuster (~£6 each to replace!).



One is still usable so at least I can put them back while I wait for replacements.

Now the acid bath (I love saying that) was empty so I chucked in a front disc, literally and splashed acid everywhere :-( also if it gets into a cut on your hand it stings (always wear appropriate protection)!



Have a slightly sci-fi picture, the bubbles/fizz is coming from the vented disc, has done a good job of cleaning them up. Any reason I can't use this method to clean up some alloys (except fop the size of 'bath'?)

You can see them, and the discs, nicely cleaned up and painted with Hammerite above. The next issue was as the discs are bigger they didn't fit in the back-plates, bit of grinder action sorted that out. I didn't want to remove hub etc, if I do in the future I'll either take them off completely of fit the 1.8 ones.



Next up installing coil-overs, my spring compressors are too large to use on the springs, and the free length of the springs is greater then the length of the coil-over (or so I thought). First attempt was to use a jack under the wishbone to force up the coil-over, as below.



Didn't work, I then realised I was being an idiot and pulled out the piston rod but then the unit wouldn't fit in the space between the top mount and the lower wishbone. Stuck the jack and a block of wood above the wishbone and pushed it down (remember I'm doing this on my own) and was able to get the coil-over in with top-mount already fitted. No pictures as I got carried away with my great thinking, will take some when I do the remaining side.





Drivers side all fitted up waiting for calipers. Bit of a pain that there's no disc retaining screw as it flops all over the place.

I've hit a delay as I have a few missing items;

• one top mount nut (it fell off and is now in an inaccessible place) - will buy magnetic pick-up tool and also some M6 nuts/washers
• no banjo washers for the brake hoses - ordered (Hel) on eBay
• lost a washer from the coil-overs - emailed Gaz got a replay 06:15 this morning one on its way FOC, great service.
• lost spring washer for bottom shock bolt - will buy stainless one(s) from Screwfix/Toolstation
• handbrake outer adjusters ordered from IL Motorsport in Germany (none in stock at MX5parts or Autolink)
  

and of course I've got to cope with the non captive captive nut...

Good stuff - that perseverance has paid off!

Looking at your derusting efforts, did you ever look at that product deox c?? Google it you fill an old bath with water put 25g of deox in it and it chemically breaks down the rust to clean metal over 24hrs and is good for doing plenty of parts

I will save you the bother, the gel form of deox is not great, but the deox c powder is highly recommended