1996 LS400 Project. Let the fun begin.....!

Howplum · May 27, 2021

This week I have been overhauling the parking brake system because I felt it's effectiveness was a bit marginal, even though the MoT tester passed it last year. In common with a lot of drivers of automatic cars the original owner never used it, so it was no surprise to find that the left side cable was seized. I had already acquired the replacement cables, along with new shoes and a fitting kit, so for those of you who might be interested, this is how I did it. I won't pretend it's quick, or easy, but it is doable. The most fiddly part is relocating the hold down springs for the shoes, but by trial and error I figured out the easiest way to do that.

The hold down springs can only be accessed through a hole in the hub, so the car needs to be in neutral. I discovered the hard way that it best to do this BEFORE removing the brake caliper, because the brake pedal has to be depressed to change gear.

With the brake calipers out of way and the discs removed I thought I should address the rusty dust shields, so I cleaned them, treated the rust and gave them three coats of Rustins Metal Paint, which I now prefer to Hammerite. Once I have done the other side that should stop them getting any worse.

https://www.toolstation.com/rustins-quick-dry-metal-paint-smooth-satin-500ml/p39925#reviewTab

Not having the special tool the hold down springs were released using a selection of pliers, following which the springs at the top could be disconnected and both shoes removed as far as possible. However, the rear shoe is connected to the cable, and because on the left side it was seized I had to cut the cable nipple off in situ, enabling the shoes to be removed completely. The right side was easier to disconnect, not being seized.

These are the various components:

The two 6mm bolts holding the cable to the dust shield both sheared, but for the new cables I used stainless steel ones.

Each cable is held by three clips, two of which were very rusty, although the bolts came undone with penetrating fluid and patience. I "cooked" everything in a rust removing solution, treated any remaining rust and then sprayed them with a coating similar to Waxoyl.

The cables need to be disconnected from the U shaped compensator above the propshaft, and this will be easier with the triangular plate removed from the rear Y joint on the exhaust. No doubt the bolts will be rusty though, mine were.

The next job was to separate the actuating lever from the back of the rear shoe, which is held on by a C clip, Strangely this clip is not sprung, so is removed by levering apart the ears, taking care not to lose the shim.

The cables are handed, and colour coded, because they have different fittings on the end, which will be obvious once under the car.

Reassembly involves installing the cable first, which should then be attached to the actuating arm before anything else.

Note that the pins for the hold down springs are different. The cranked one goes to the rear because it needs to clear the actuating arm attached to the cable.

Insertion of the hold down springs caused me the most grief, due to limited access, and it took me well over 2 hours, a selection of pliers and dollops of grease to get everything in place on one side.

I tried tying down the springs with cable ties, but that didn't help much, because it was difficult to grip, push and turn through the aperture in the hub, whilst making sure all three components didn't fall out.

I know there is a special tool for locking the top cap onto the pin, but it doesn't look as though it grips, so wouldn't be much use where there is limited access.

My final idea was to drill two 2mm holes in the top cap and use a pair of suitable circlip pliers to feed the top cap and spring through the hub aperture. The lower washer was fixed to the shoe with a small amount of grease and the spring was also located within the top cap with some grease. Because I could now grip, push and turn the top cap, the job was easy. In fact it was probably quicker than typing this paragraph! You will have to keep the pin in place with your finger, because it's not fixed in any way.

The lump of wood is to hold the shoes against the dust shield, otherwise you will be fighting that as well.

This is an extract from the repair manual explaining how to adjust the system.

PARKING/EMERGENCY BRAKE 1. With a force of 66 lbs. (30 kg), push down on parking brake foot pedal while counting clicks. If 5-7 clicks are not counted, parking brake requires adjustment. 2. Fully release parking brake. Raise and support vehicle. Remove rear wheels. Remove adjuster hole plug from rear hub. Install wheel lug nuts to hold rotor in place. Turn adjuster (expanding parking brake shoes) until rotor binds. Turn adjuster back approximately 8 notches (until disc turns freely). 3. Install adjuster hole plug. Install rear wheels, tighten lug nuts to 76 ft. lbs. (103 N.m). Locate parking brake cable adjuster under vehicle. Loosen adjuster lock nut and adjuster until parking brake pedal travel is 5-7 clicks. Brake Pedal Height 5.27-5.66 (133.8-143.8) Brake Pedal Free Play .04-.24 (1-6) Brake Pedal Reserve .2.76 (70) NOTE: If clearance between brakelight switch threaded shaft and brake pedal stopper is correct, brake pedal free play should be correct. If brake pedal free play is still not correct, there is another problem in the brake system. NOTE: If adjustment cannot be made within range of adjuster, remove drive shaft and make adjustment at cable pull rod. See AXLE SHAFTS - RWD article in DRIVE AXLES.

The parking brake now works as intended and the car passed its MoT test today with flying colours.

Now then, what's next on my list?

Spacewagon52 · May 27, 2021

Brilliant! Well done! Beyond my capabilities!

Malc · May 27, 2021

18 minutes ago, Howplum said:

Now then, what's next on my list?

a well deserved cuppa or several methinks ........ well done

Malc

Phil xxkr · May 27, 2021

9 minutes ago, Spacewagon52 said:

Brilliant! Well done! Beyond my capabilities!

Hard enough to read let alone do 😂😂

Howplum · May 27, 2021

I began working on cars when they all had drum brakes, so I had some idea of what to expect.

Mikaelse · May 27, 2021

7 hours ago, Howplum said:

I began working on cars when they all had drum brakes, so I had some idea of what to expect.

Yeah mee too. Those where not better days. I did the misstake of doing the parking brake on my 1995 and not properly oiling the cable (Original cable I think) . Only very limited attnetion with a few squirts of WD40. It became not very cooperative again quite soon AND it did not always release well.

I wore down the new set of parking brake shoes in under a year. Probably not very healthy for the bearings either to run warm from time to time, Replaced the brake shoes one more time and this time i exersized the cable and gave it squirts of WD40 MANY times. Felt that was needed.
Has worked well since. I do use the parkingbrake from time to time to keep it working but quite sparingly. I also check that it is not dragging when I have used it. Ok so far. Neutral when rolling real slow will tell. Feeling center of rims will also tell if it is dragging badly for a while (warm).

Howplum · May 27, 2021

I'm sure I remember some cars having grease nipples on the handbrake cables.

Mikaelse · May 28, 2021

14 hours ago, Howplum said:

I'm sure I remember some cars having grease nipples on the handbrake cables.

Perhaps at some point on a very short cable. Here in sweden with sometimes -30 C (rare but I rememeber winters with weeks duration, 1986/1987 even here in Stockholm). puting grease in a often rather long cable at low temperatures would make brake grease near solid and impossible to operate. Light grade Oil should be used here at least.

Howplum · May 28, 2021

Recently the foot pedal for the parking brake has not been returning fully, the result being that the warning light stays on. However, if I hook my foot under the pedal and lift it slightly the light goes out.

According to the diagram below there should be a "46305 - Spring, return parking brake w/damper" somewhere around the equaliser assembly, although I can't remember seeing one when I was under the car the other day. Perhaps it has gone rusty and fallen off.

The other possibility is "46220 - absorber assy, parking brake pedal return" might be faulty, interfering with return of the pedal in some way.

Does anyone have experience of this issue please?

http://www.japan-parts.eu/EU/3/460046B.png

Malc · May 28, 2021

never had to replace parking brake shoes on any of my Ls400's and 250k miles +

but then I rarely ever use the parking brake ....... put her in P and you should be ok unless you're parking on the tip of the Matterhorn and afraid she might drop down :yes:

never had MOT Advisories on this issue either

Malc

Howplum · May 29, 2021

Taking a break from crawling under the car I thought I would investigate the aerial, which is stuck in the halfway position. The motor works, but on dismantling I found the toothed cable had parted company with the telescopic rod. I replaced the rod only a year ago, albeit with a cheap £15 item from eBay, so lesson learned.

Lexus want £126 for the same thing, which is a bit rich for me.

I seem to remember I bought a replacement mast for an old Mercedes from a specialist supplier, which certainly lasted more than 12 months, but for the life of me can't find out who. Does any one have any ideas? Was the Denso aerial assembly fitted to other models in Japan perhaps?

The part number for the mast is 86337-50141.

Megazip have them listed for $48, but what with shipping and other charges it won't be much cheaper than the UK price, I suspect.

runsgrateasanut · May 29, 2021

Perhaps it was a Hirschmann Auto 2050 ?

https://www.ebay.co.uk/itm/313076064253?

Howplum · May 29, 2021

Now you mention it, the Mercedes aerial was Hirschmann, but the Lexus one is Denso. The part numbers on the assembly are Toyota 86309-50051 and 100631-4160.

Howplum · May 29, 2021

I've just found this website:

https://www.allcarpartsfast.co.uk/lexus/lexus-8633750140-86337-50141/

Apparently a genuine part at half price at £61.50.

Malc · May 29, 2021

2 hours ago, Howplum said:

Lexus want £126 for the same thing, which is a bit rich for me.

can you find one from a " breaker " maybe ?

Malc

Howplum · May 29, 2021

That's certainly an option @Malc.

In the meantime I found the company I was thinking of, car-masts-uk, who advertise on eBay, so I have sent them a question.

Howplum · May 29, 2021

In case anyone else has the same issue, this is the one:

https://www.ebay.co.uk/itm/Toyota-Camry-Carina-Lexus-GS-LS-RX-SC-Electric-Aerial-Power-Antenna-Mast-/174698955581?_trksid=p2349624.m46890.l49286

Tulpen · May 29, 2021

1 hour ago, Howplum said:

In case anyone else has the same issue, this is the one:

https://www.ebay.co.uk/itm/Toyota-Camry-Carina-Lexus-GS-LS-RX-SC-Electric-Aerial-Power-Antenna-Mast-/174698955581?_trksid=p2349624.m46890.l49286

I can concur with that. I had the same problem with my '94 LS400 and the Camry insert fixed it.

rich1068 · May 30, 2021

Are you sure that £126 isn't for the entire assembly? I'm sure I paid considerably less than that for genuine Lexus when I got the GS and then the LS. Enormously satisfying when the motor takes the cable off you

Howplum · May 30, 2021

Lexus Parts Direct are quoting £89.67 on their website for the mast. I can't find a listing for the complete assembly, although Amayama's website says it's permanently out of stock.

The Lexus dealer quoted £17 for the parking brake return spring, and 3 weeks delivery!

rich1068 · May 30, 2021

1 hour ago, Howplum said:

Lexus Parts Direct are quoting £89.67 on their website for the mast.

That sounds more like it. Still a bit rich but at least they're genuine. I had no problem getting hold of them from Lexus Sheffield.

Howplum · May 30, 2021

I've ordered one from car-masts-uk, at £28, because I have used them before and never had a problem.

Time will tell though.

runsgrateasanut · June 1, 2021

Howard,

I'd be grateful if you can let me know the length of the "tail" on your new Mast. I have a spare but suspect it is short and don't want to bother to remove the unit if it is going to be a waste of time.

Previous owner put in a cheapy and it makes a strange "grinding sound" as it emerges. Its a five part Mast.

Thanks Stuart

Howplum · June 2, 2021

I've been investigating the reluctant extinguishment of the parking brake warning light to try and get to the bottom of what is only a small issue, but irritating nevertheless. I've seen it mentioned on some US forums, so is not uncommon.

Under the car the return spring is present, together with its "shock absorber", which looks suspiciously like a lump of rubber. Anyway, nothing is binding, but I lubricated appropriately anyway.

Originally I suspected the little plunger switch on top of the parking brake assembly, but it's a real s*d to get at. Instead, I decided to check the shock absorber (gas strut) that prevents a bang when the parking brake pedal is released. One end is attached to the pedal and the other to the mounting bracket. It acts on the extension stroke, so slows down the speed that the pedal returns at. In this case it looked as though it was providing too much resistance towards the end of it's stroke, thus meaning there was a delay of a couple of seconds before the pedal was fully retracted, and thus the plunger switch activated. I disconnected the gas strut and the pedal returned immediately and the light went out, so it looks as though I need either a new or rebuild gas strut. The only downside is that the pedal now makes a noise, just like a Mercedes, which I assume is what Lexus were trying avoid!

Lexus want about £75 for a new one, so I am now investigating alternatives from SGS Engineering and others.

Razor61 · June 2, 2021

2 minutes ago, Howplum said:

Lexus want about £75 for a new one

I had the same issue and bought an OEM one from Lexus, fitted it and it did make a little bit of a difference but still not perfect. There is some adjustment on the assy to adjust the length, I read the manual and followed the procedure (pic below) but in the end I think I ended up using trial and error until it worked correctly. I don't know if the old one just needed to be adjusted or the old one was in fact knackered and the new one needed adjustment to fit. I compared the new one and the old one for resistance and I couldn't see much difference.