Brakes and Firewall Rust

After removing brake lines, steering column and pedal box the full extent of firewall rust is revealed

Brake master was leaking onto floor

2 brake servos -OTT?

Removed with lines attached, rubber pad was hiding ......

THIS!! Anyone got a spare firewall?

Useful tools

Don't really need an excuse to buy more tools but these 3 small items saved much cursing and rounded off nuts, and no one wants there nuts to be rounded off!!

6mm Hex head on 1/2'' drive breaker bar - that Allen Bolt was tight!

Flare nut wrenches - 11mm and 14mm, all brake unions came apart without damage

Steering column mposition marked with whiteout marker

Gas pedal position with other side resting on inner wing

Most of the firewall is now exposed and there is plenty of welding to to there, spot weld drilling and patch panel fabrication here we come!

Engine Bay Stripdown

More boring photos for reference!

Engine Out

The gearbox was removed from below after disconnecting the remote, needed to refer to the manual to work out how to remove the tension bush (4), needed to push out the small pin with a pin punch which expanded the bush enough for it to slip out. The grub screw at the back of the shifter (18) eluded me for a while as it was covered with road dirt and oil http://www.realoem.com/bmw/showparts.do?model=ST13&mospid=47129&btnr=23_0775&hg=23&fg=15


After removing bell housing bolts and the starter motor the box with a couple of shakes came loose and was lowered gently to the floor by getting under it and resting on my chest (box is light and have more control than a jack!


Then onto the engine, very easy to remove as the gearbox was off there is no need to tilt the motor and it came straight up after taking the weight on the engine hoist and removing engine mounting bolts.

Going

Going

Gone

40 years of oil and dirt

Good Preservative! Not for the rubber parts though

Flywheel was removed before mounting on engine stand and lowered to the ground

Needs a skim, ring gear seems OK

Resting place for a while 

Up on axle stands

Finished cleaning the soundproofing off the floors- came out nice

The factory primer holds on really well, worst rust in the footwells

Raised up on axle stands, exhaust came out really easily, no rounded nuts or stripped threads that usually occur on exhausts

Nice to work under now

Oily

Probably downpipe only will be retained

'Guibo' off next, think this will need replacing has a couple of tears on it

Don't think this has been removed alot - nuts and bolts in great condition

And finally the gear shift, held in by a hex head grub screw

After inspecting the underside i couldn't see any more rust - good news.

Think the engine and gearbox oil kept the rust at bay!

Think i will drop the gearbox from underneath, making it easier to pull the engine. When it goes back together the engine, gearbox, front subframe and suspension will go in as a unit but until most welding is completed i want to leave subframes in

Engine Bay Stripdown Pt2

More photos to help me reassemble

Alternator wiring - note small earth wire to engine block

Wiring routing

Wiring routing, behind brake booster

Starter motor connections

Note mark for TDC No 1 Cylinder

Hole in housing - factory option?!!

Throttle linkage

With a video for good measure!

Need to put car on stands to access underneath now

Engine Bay Stripdown

Removed Alarm, Water Bottle, Coil and Radiator, photos for reference

3 bolts holding waterbottle were rusty and not captive

Lurking under the water bottle

Distributor HT Leads

Top and Bottom Radiator Hoses

For Reference

Steering wheel, choke and wiring

Took a break from cleaning soundproofing to remove steering wheel and other bits and pieces in the cabin to make access to the floor easier, wheel came out easily, then on to the stalks

Left Hand Stalk wiring

Spliced in wires from the alarm

Tape removed to reveal some butchery

Ignition wiring, note grey wire that comes from indicator stalk

More wiring mess

??? will consult the manual

Choke was removed next, easiest to separate at the carb end

Nothing very exciting really, although these photos will help me in putting everything back together, just read the blog backwards and should be sweet! 

Sound insulation removal using Dry Ice

I wanted to try the dry ice method of removal and yesterday bought 5kg of pellets

Dry Ice pellets

Turned out the boys shovelling it into the chillybin were generous and i got over 10kg! Thanks guys.

I then shovelled the ice into a dozen plastic bags, spread them over a section of floor, covered them with a couple of sacks and left for approx 1/2 an hour. First section i tackled was the passenger floor

1st section done, took less than 10 minutes - Sweet

I found using the air hammer very effective, angled at about 45 degrees it shocked the tar off in chunks, (the dry ice having made the tar brittle first) I did try hammering with a dead blow hammer but felt there  was more danger of bending the floor. Here's a video of the system in action, excuse quality- its hard to film with one hand and hammer with the other!

I thought it worked very well on the floorpan and some of the transmission tunnel panels, on the rear wheel arches not so well i think because of the type of material and being vertical it was hard to keep the dry ice in position.

Generally floors are good

Rust coming through here

The worst area, fairly easy to fix though

Cutting required to reveal more

About 15kg (33lbs) taken out

Final verdict - $25NZ well spent, having already used hot gun and scraper on a couple of other areas i would rate this method as better, easier and a lot more fun! It removes i would guess 98% of the tar and the rest will be removed with hot gun and scraper or solvent. It was not so effective on the seam sealant and areas of this will need to be scraped off where i need to weld