Slow restoration: 91 E30 325iC

[jonoe30 53]

After completing a total rebuild of the suspension this year on my E30 convertible I thought I'd create a long overdue project thread to document the work in one place and add in some of the work completed previously...

Purchased in Jan 2014 as my daily driver it has been getting attention in fits and starts over the years as time has allowed, and for the past few years was relegated to weekend driver with the purchase of a sturdy Toyota TownAce 60HP diesel (now gone)

My main goals with the car are to ensure everything works exactly as it should, keeping it looking original, with mild upgrades (it's a convertible after all) & modernisation as things are given attention.

Plans (I'll make a post for each in this thread):

-Refresh cooling system/timing belt replacement - Completed May 2014
-Replace convertible roof fabric/seals - Completed Apr 2015
-Fix electro-mechanical folding mechanism - Completed Dec 2016
-Replace all suspension/bushing components - Completed Apr-May 2019 (Special thanks to Nathan (zero))
-Rebuild diff (+mild upgrade - Z3 torsen... while you're in there eh?) - May 2019 (Kayne Barrie Motorsport)
-Rebuild head - TBC, planned Jan 2020 (slow oil leak from head gasket down block... a case of while your in there - no coolant mixing/ loss or compression issues)
-Convert AC to R134a - TBC (all parts sourced)
-Audio upgrade - TBC (CD43 - E36 CD player for something tasteful in the dash, small inline Alpine amp + Bluetooth adapter sourced)
-Install new alarm system - TBC (and tidy loom behind dash from butchered install of old ?Dynatron system)
(Above 3 to happen concurrently with dash out)
-??? Re-dye leather (keeping original patina) - TBC
-??? E46 rack swap - TBC (purple tag sourced - still pondering whether I want to make this change, considering certification requirements)
-??? Respray (same colour) - TBC

The car was had many small issues when I got it - see post:

Original build sheet (pretty well spec'd, NZ new, 'special request' is the high-stop on the boot):

[jonoe30 53]

Refresh cooling system & replace timing belt - April 2014, 165,000km

I didn't have any overheating issues, but everything was original and looking a bit sad. Was the first project on the car after I purchased it, and I really just wanted to pull it apart and have a good look & get some preventative maintenance done

Parts:
-All new hoses
-New radiator (upgrade to 'hot climate' width)
-Brackets & shroud for above
-Thermostat housing
-Blue & brown sensors
-Fan clutch
-Water pump (GRAF)
-Timing belt & tensioner
-Auxiliary belts
-Temperature resistor for aux. fan
-BMW coolant

Got everything out, also removed the intake manifold, cleaned up the exterior of the head, sent the injectors out to be reconditioned, inspected & adjusted valve clearances. Replaced cambelt & tensioner (cover had been misfitted, with the tensioner rubbing!)

 

[jasera94 29]

Epic! i've also got an E30 Cabriolet project on the go.   

[zero 1160]

That engine looks nice and clean now.

[jonoe30 53]

Replace convertible roof fabric & seals - April 2015, 177,000km

After almost a year of enduring a 'leak free' roof (as described by the previous owner) it was time to replace the leaking convertible roof fabric. The leaking was coming through the perished stitching that connected the fabric to the frame... most of the loops had separated from the frame (don't drive with your soft top closed, windows open at high speed!).

Parts:

-New original pre-cut 3 layer fabric (canvas, rubber inner, cotton interior lining layers)
-New front & rear bow seals
-New tension straps
-Sikaflex 225 (original rubber sealant as used at factory)
-ADOS F38 high heat contact adhesive
-Stainless steel high strength screws for tension straps and rear bow seal retainer (Auckland Engineering Supplies is very useful)
-Litres of solvent (for old glue)
-Rust-Oleum black satin spray paint

Unfortunately I don't have a lot of photos from this job, but I used the original factory service video of canvas replacement (I have a copy if you need it) + the instructions that came with the fabric. It was easy to tear off the original fabric, with frame attached to car, then a few days with clothes soaked in solvent wrapped around glue cover bows (horizontal bars fabric attaches to) to remove all traces of the glue.

Once the old glue was removed, I decided to remove frame, lightly sand it to remove some spots of corrosion and respray all parts with a black semi-gloss/satin spray paint.

Refitting the frame is straight forward, however be prepared to spend many hours with shims getting correct alignment of frame to body (happy to assist people with this!).

Then it's a process of re gluing the canvas to the frame (there are specific alignment cuts in the canvas to attach this correctly). It's very important particular attention is paid to the way the two layers of canvas are attached to the rear bow, and the final layer needs to be glued so that it pulls the canvas in around the rear bow. Done correctly, the canvas should meet at almost a right angle with the rear tonneau cover when it's closed.

Some original inscription from the factory on the old canvas

Before it's first outing I also used 303 Canvas protectant (kind of like scotch guard) to protect the fabric and make the surface hydrophobic

I reapply this every 6ish months - 4 years on it's still looking near new:

I also picked up an original rear window 'bra' on german Ebay to protect the rear plastic screen if it's parked outside on a hot day (it's been garaged since the roof replacement):

Edited October 3, 2019 by jonoe30

[jonoe30 53]

Replace all suspension/bushing components/diff rebuild - Completed Apr-May 2019, 198,000km

Since I purchased the E30, Previous owners had fitted Vogtland springs and Boge fronts with standard rears... impractically low, soft, paired with with the wrong shocks. Add to that almost 200,000km on the clock and most things were getting soft/perished, the rear beam bushings were particularly shot adding some exciting rear wheel steering to the mix when avoiding pot holes.

After countless hours of research and sleepless nights pondering what I'd do, I purchased Bilstein B8 shocks & H&R Sport springs a few years ago, but they sat in the garage (shocks stored upright), being too busy with work to devote the time to completing the job.

It's never going to be a track car being a convertible, and I'm not an overly 'spirited' driver, but I didn't want to return to the lofty heights of factory suspension & wanted something firm but controlled. I picked up the strut bar & cross brace from Garagistic on sale in the hope to keep everything nice and tight up front and make the most of the sport shocks & springs (I'm sure I could find stiffer/higher performance versions of these, however I liked their understated design).

This year after quitting my job it was finally time to get them fitted. Crippled with an acute case of 'while you're in there' I had brought all other bushings for front & rear, all new wheel bearings (front left had failed a warrant). Diff was whining rumbling like there was no tomorrow so off to Kayne Barrie for a rebuild.

Parts:

-Bilstein B8 sports shocks
-H&R Sports springs
-Garagistic front strut brace
-Garagistic front lower x-brace
-Original 3.73 diff rebuilt with Z3 torsen
-Rear beam bushings
-Rear trailing arm bushings
-Rear sway bar bushings & end links
-Diff carrier mount
-Front control arms
-Front rose-jointed sway bar end links (Ford Mondeo 'upgrade' from E30 wiki)
-Front strut mounts
-Front tie-rod ends
-Spring pads
-Front disks, pads & caliper rebuild kits (rears replaced 2 years ago)
-Parking brake pads & hardware
-New brake lines (x6)
-Wheel bearings (x4 - FAG, original supplier as noted on the old ones)
-Exhaust hangers & gaskets
-Engine & transmission mounts
-Various new bolts, nuts for drive shaft, rear beam, etc.

All bushings/mounts/end links/control arms Lemforder. Brake rebuild kits & lines ATE, standard Bosch pads.



I removed the exhaust directly from the headers & removed as one piece. Then dropped the rear subframe as a complete unit and disassembled (loosening the half shaft retaining nuts before removal). The subframe came away easily as the rear beam bushings were completely separated

You can see a 3-axis puller attached to the half shaft & hub... this was useless requires a press or back of an axe with spacer!


Once this was all apart, I took these round to Nathan's (zero) house and with his help & the right tools we got all the old bushings and bearings out in an afternoon! This would have been a properly horrible job without his help!

There were only a few very minor corrosion spots on these parts due to the copious amounts of factory protectant wax that was still clinging on, nonetheless while it was all out, I sent it off to be sand blasted, primed & painted:

While this was all out, gave the under body a good scrub & check for corrosion... again the factory wax and face-lift galvanizing process had held up well. Once all the parts were back from the paint shop, I pushed all the bushings & bearings back in with a press

Received the diff back from Kayne and set about re-assembling everything!

(assembled on the car)

The old front sway bar end-links vs the rose jointed ones

Front strut bar fitted (required repositioning the clutch fluid reservoir).

Unfortunately I've only taken it for a short run up the road (needs a wheel alignment) as I was down to the wire getting it reassembled (read 2 days) before I headed off to South America for 6 months (in Peru writing this!)... For now it's up on stands in my parents garage... Looking forward to getting it back on the road and will post re the improvement after I've had some time on the setup (back in December)!

A few quick photos for ride height reference before it went into storage:

Special thanks to my father for many hours of assistance, sweat and muscle. Nathan for his time, knowledge and good conversation. Kayne for getting the diff turned around before I headed to South America, during what was a really busy time for him!

 

Edited October 3, 2019 by jonoe30

[Palazzo 427]

Great write up and work!

I don’t know if you’re inspiring me or terrifying me to do something with mine.

[jonoe30 53]

Thanks There's a lot to keep maintained, but they are generally a pleasure to work on... analog by today's standards, but well engineered... dig in (to the work and your pockets ?)! In saying that I put off these bigger jobs for far too long... quite a bit to tackle at a time. Doing the roof is particularly rewarding haha

[NZ BMW 368]

Wonderful work, well done! 
 

I always love these project threads - there is a certain tipping point where doing your own work just goes to another level as you can take the time and go the extra mile. 

[E30 325i Rag-Top 2914]

Nice car, nice job and nice write-ups!

One thing I would suggest you check before you do the head gasket is the rocker cover gasket and in particular the 4 U shaped rubber inserts at the front and rear. The inserts go hard from the heat cycles and start to leak oil, which runs down on to the head gasket.

Much cheaper and easier to fix!

[GetCam 15]

Have you ended up coming back to New Zealand since your trip?

[Hiflying206 0]

Hi Jonoe30, I have just been reading your post regarding the soft top replacement. I purchased my dream 1986 E30 325i convertible about 10 days ago, despite being in immaculate condition, the roof has a few issues in particular the operation of the manual roof.

You mentioned that you had a link/copy to the BMW service video for the roof replacement. If you still have that, I would love to see it.

 

Regards

Stu 

stuart.clentworth@hotmail.com