Skywing Brake Failure

Life Cars & Motorcycles
1

Pedal went to floor. If I’d been driving an auto I think I’d have crashed, but I stopped it on the gearbox/handbrake

Dark, and I had a plane to catch, so I parked up and left it.

3 weeks later, no leaks visible, reservoir level OK, pedal firm.

I’m thinking impending/intermittant master cylinder failure.

I’ll try flushing with fresh fluid just in case it was absorbed water boiling in the fluid, which is overdue for a change, but I wasn’t driving it hard so it doesn’t seem very likely.

I’d bet you can’t get rebuild kits or new master cylinders here in Taiwan. Does anyone happen to know different?

2

Long pedal travel can be caused by mechanical problems.

Pad knock back due to worn wheel bearings, perhaps loose bits on hub/disc. Pedal to floor though is extremely extreme for such a cause.

While sitting in the car park pads will not get knocked pack.

Good emergency action with long pedal is to pump brakes (while doing other stuff too).

+++

Some cars with dual circuit brakes had/have an isolating valve that isolates an open hydraulic circuit. Sits between circuits. In the event of a pressure differential between circuits it moves and cuts off flow to low pressure (leaky) side. Once done it is done, needs manual reset of some kind, perhaps by buying new one in some cases. Perhaps yours has popped?

Info all from pre-1980 era.

3

Thanks for your reply.

It was pretty sudden/extreme, so probably not pad mechanics.

I was turning left prior to waiting for a gap in the opposite lane so I could complete a U-turn, and was lucky not to run into the oncoming traffic and get T-boned. Given the full-lock manouvre, I initially assumed one of my front brake hoses had ruptured, but they’re intact.

I see what you mean about the isolating valve, since it would explain the “recovery”, but a search of the G100 manual (I don’t have a G10/11 body manual but there’s a lot of commonality with the G100) doesn’t turn up any mention of such a valve.

Best guess at this time is a failing master cylinder. The G100 manual, irritatingly, shows 2 master cylinder/brake booster assemblies, referred to as 6 inch and 7 inch. Not sure what this dimension refers to, but since the 6 inch MC looks longer, it might be the diameter of the brake booster/servo.

Also not currently sure which of these, if any, I’ve got.

Last time I went to a Daihatsu dealer here in Tainan they just gave me the “too old” brush-off, but if I get stuck I might try the Kaoshiung dealershp the previous owners took this car to.

4

Could be bad master cylinder cup seal, but could be other things. After it’s sat for a while, try pushing the brake as slowly as possible and see if it goes to the floor over time. If it does, then it’s definitely a bad seal and needs replacement. Even if it doesn’t go to the floor it’s still possible to be a bad seal, but not likely because they don’t repair themselves. Could be pad knock back, but it would have to be extreme to happen all at once like that. It would take either, bent rotor, super loose wheel bearings, or loose caliper. If it was really low on brake fluid, it’s possible it could have sucked up some air during a turn. If you got the brakes really hot, you could have had fluid boil. Especially in Taiwan the brake fluid is likely saturated with water so the boiling point is quite low. Fluid boil does not always occur during the brake event. It’s common to be a delayed event because it takes time for the heat generated by the pads to transfer through the pistons and then into the fluid. could be delayed as much as 1 minute.

Most important, make sure you get it fixed. If it happened once, it will happen again, and next time you may not be so lucky.

5

[quote=“PDGNKG”]
Most important, make sure you get it fixed. If it happened once, it will happen again, and next time you may not be so lucky.[/quote]

Thanks.

Making sure I get it fixed isn’t necessarily straightforward with an intermittant fault, but I appreciate the need for caution.

I thought I’d replace the brake fluid and a dodgy-looking (but intact) brake hose before I did anything else, but currently can’t get the lower hose union (14mm) undone, so I’ve got a half-drained brake system and a half-replaced brake hose.

Not a good idea to leave it like that for very long, so I’ll try local heat and a better/extended spanner tommorrow night.

I’d like one of these, but that’ll require a trip to Kaoshiung at the least, if they are available in Taiwan at all.

6

Doubt you are gonna find one of those nifty tools, but you should be able to get a normal flare nut wrench at a half decent tool shop. I picked one up in Taipei for about NT$100 or so.

If you’ve already rounded off the flats on the nut, you probably aren’t gonna be able to get a flare nut wrench on it …

7

[quote=“monkey”][quote=“Ducked”]
I’d like one of these, but that’ll require a trip to Kaoshiung (Gaoxiong) (Gaoxiong) at the least, if they are available in Taiwan at all.

[/quote]

Doubt you are gonna find one of those nifty tools, but you should be able to get a normal flare nut wrench at a half decent tool shop. I picked one up in Taipei for about NT$100 or so.

If you’ve already rounded off the flats on the nut, you probably aren’t gonna be able to get a flare nut wrench on it …[/quote]

No half decent tool shops in Tainan that I know of.

The all-night hardware stores sell lowish quality (“Sellery” brand) open-ended C-spanners with a flexible socket on the other end. I could probably fit a pipe over the socket to give me leverage, but of course there’s a risk the spanner will just open-up and then round the nut. Spose that might be why normal open-ended C-spanners are generally so short.

Getting a standard flare nut spanner (not sure how much better they are. more grip but less metal, generally) would also require a trip to Kaoshiung, which’d mean leaving it until the weekend.

Decisions, decisions. Spose best available tool for the job is the way to go, though, even if it means delay.

Not sure how long I can get away with parking it where its at though, neighbour-wise.

8

“Getting a standard flare nut spanner (not sure how much better they are. more grip but less metal,”

They are a lot better than a normal open ender. Usually much deeper because access is never (ok rarely) restricted in that way.

If there is room a stilson always does the trick. The trick of course may result in breaking something:-( I had one about 6 in long that was robust enough to take a long pipe - most essential tool in the box for working on old cars. I tried quite hard but never broke it.

I think it was exactly one of these:-
ridgid.com/us/en/straight-pipe-wrench

A good Q&A on the page.

“What is the maximum torque that a 36” and 48" straight pipe wrench can handle."

Surprisingly the answer is not “it depends on how long a pipe you have”.

“The maximum Torque for the 36” wrench is 45,000 inch pounds.
The maximum Torgque for the 48" wrench is 52,000 inch pounds."

That equates to 1250 pounds and 1080 pounds respectively at the end of the handle.

So the answer is - it depends on how strong your long pipe is;-)

I didn’t realise that they were actually designed to be used with a pipe on the handle (or a tame Elephant as an assistant mechanic). They did seem ludicrously robust.

I did have another one of the same make that was abut 15". Nothing on any car ever resisted it (+pipe).

9

Thanks.

I keep hearing that about Stilson’s so I suppose it must be true, though I’ve never tried one. Now might be the time.

I suppose I suspected that, being adjustable, they’d not fit properly, and would just slip and mangle the fitting.

(Like an adjustable spanner doesn’t. Very expensive adjustable spanners might, I suppose, but I’ve never had a very expensive one).

Possibly the general aura of brutality put me off a bit.

Going through to Kaoshiung tommorrow to see what I can find. Of course this is probably a distraction and I really need a new master cylinder unit, but at least I get to buy some more tools:)

10

“I suppose I suspected that, being adjustable, they’d not fit properly, and would just slip and mangle the fitting.”

Although they look similar to some other adjustable spanners they have subtly different geometry and also teeth. They self tighten when loaded. There is no tendency for the jaws to spread, quite the reverse. They are designed to and do work on cylindrical pipes. They work by means of the the self tightening action and the sharp, hardened, ratchet-shaped jaws.

They do of course mark the surfaces by their self tightening action and the sharp jaws but rarely enough to render the component unusable with a normal spanner if carefully adjusted and applied. Adjust them as tightly as possible onto a pair of flats and increase pressure gently making sure that they grab square on the flats. Once set - heave :-))) Used without care they can do more damage. For best stability make sure the nut is centralised in the jaws as far as is possible (since you do not have an infinite pipe) and is as deep in the jaws as can be managed.

Of course the head of the tool is much larger than a normal spanner but not much more than an adjustable. I have most certainly used them on brake pipe unions in the (distant) past.

The “Ridgid” brand ones are indeed very rigid and grip very well when off-centre. Others that are not so well made/designed and may be more difficult to use on a brake pipe joint as the “nut” will likely be well away from the centre of the tool.

en.wikipedia.org/wiki/Pipe_wrench

They are apparently known as Baboon Wrenches in parts of Africa:-)

11

Tool Time Taiwan. (Pretty small audience, I’d guess)

I got a King Tony 13-14 mm flare nut spanner for 170NT at my favorite Kaoshiung tool store, along with a Force 11-12 mm one, (lower quality but still OK I think, based on some Force stuff I’ve used in the past), for 70NT. The other good (better?) Kaoshiung tool store had the King Tony 13-14 mm for 150NT

The so-so Kaoshiung tool store had a Black Hand 6-piece set covering 8-19mm for 750NT. I’m a sucker for sets (pro’s don’t seem to go for them) and have liked Black Hand stuff in the past, but there was a piece missing, and I couldn’t get the laoban to understand that I wasn’t paying marked price for a part-set.

The GKTS had something quite like that apparently nifty ratcheting thingy above, for 854NT, but double hex rather than side gripping, “Metrinch stylee”, and 14mm would need to be ordered, so I passed.

levelchrome.com/Supertool-RQ … p_372.html

Spoilt for choice for Stilsons. Fuller (who I’ve heard of) were fairly cheap at around 300NT for a 14", but there were Japanese brands that I hadn’t heard of (Neturen, Super, MCC) for 2-3 times as much. Decision deferred until I more definately need one.

Shiny new spanner shifted the lower brake hose nut, so I replaced the hose, which had surface cracking but a visbly different hose core which was intact.

New hose is apparently longer, touching part of the caliper body at one end, and the wheel arch the other end at full lock, so I’m not sure I want to replace the other one. Hose says G11 on it, so maybe the Skywing is G10, which might not still be available. Might put some of that spiral stuff people use for cable tidying, (or maybe some whipping) on it, to give it a bit of extra protection

12

How many rear-wheel brake bleeding nipples do y’all have on your cars (those of you who know)?

I evidently didn’t, since I thought there was one per wheel, but I only seem to have one on the rear right.

Seems odd, but I havn’t bled the brakes on that many cars to have a representative sample.

13

"How many rear-wheel brake bleeding nipples "

Depends on the plumbing.

I seem to recall that beam axle Fords (quite why I recall that I have no clue - what day is it?) often had a single pipe from the bodyshell to the axle, a pipe to one wheel cylinder and then a pipe that ran across the axle to the other wheel cylinder where there was a bleed nipple. So only one on the rear axle. Obviously the arrangement saved them money in some way. The wheel cylinders are normal ones and one of the pipes is connected to the “bleed nipple” hole.

Presto!
Not really clear but the cross axle pipe is, I contend, visible and no T-piece is indicated on the parts list.

capriwiki.com/index.php?titl … _Regulator

There is no one killer picture but collectively these might convince you?




The best Capri photo I found.

14

Also:- any flexible pipe contact with anything is wayyyyyyy to scary for me. Sometimes the pipe can be repositioned by rotating it (slightly) at one end or other or both before tightening the clamping nuts. You do not want torsional strain on the pipe either though.

15

Yeh. Not wild about it myself, but this may be the only replacement hose I can get for this car.

I think the old hoses look worse than they are, as explained above, though I’m sure they’d get “death trap” status in the court of public opinion.

Toss up. If I can’t find a better replacement I think I’ll keep a close eye on this one (perhaps giving it some extra protection) and replace the other one with the same if there are no early issues.

Thanks for the pictures. Bit confused though. Are you saying the last (Capri) one only has one nipple? (Fnar, Fnar)

Apparently it was a fairly common arrangement on the rear brakes of older cars, but I don’t remember seeing it before.

16

“Are you saying the last (Capri) one only has one nipple?”

The rear wheel cylinders were normal with two threaded holes. On one side there was the pipe from the master cyl in one hole and the cross axle pipe to the other side in the other hole. The other side had the cross axle pipe and a bleed nipple.

Flex hoses can look OK and be knackered. They expand under pressure and cause a long pedal. Small cars such as Minis and Imps did not have room for much pedal travel and were susceptible to running out of travel. I positively diagnosed this on one occasion by clamping the hoses at the master cyl side (I had a couple of hose clamps and resorted to mole grips for the other two). The mysterious long pedal had been causing much (even a lot of) hear tearing for a while. New hoses - fixed.

Something like a Transit had enough pedal travel available that the brakes worked without bleeding even after the system had been opened. Obviously they still got bled.

17

[quote=“JohnSmith82”]“Are you saying the last (Capri) one only has one nipple?”

The rear wheel cylinders were normal with two threaded holes. On one side there was the pipe from the master cyl in one hole and the cross axle pipe to the other side in the other hole. The other side had the cross axle pipe and a bleed nipple…[/quote]

Sorry, that was an attempt at a “Sid the Sexist” stylee joke/pun. Hence the Fnar Fnar. Embarrassed now, though I suppose I should’ve been before. :blush:

[quote=“JohnSmith82”]"

Flex hoses can look OK and be knackered. They expand under pressure and cause a long pedal. Small cars such as Minis and Imps did not have room for much pedal travel and were susceptible to running out of travel. I positively diagnosed this on one occasion by clamping the hoses at the master cyl side (I had a couple of hose clamps and resorted to mole grips for the other two). The mysterious long pedal had been causing much (even a lot of) hear tearing for a while. New hoses - fixed.

[/quote]

Yeh, I wondered if the original failure could have been the hose “ballooning”, though I wouldn’t expect that to be intermittant, unless accumulated heat was a factor, or I for some reason pressed the pedal especially hard that time, which I don’t think I did until after it failed.

Just driven it for about 15k with its one new (but apparently overlong) hose, and its shiny new brake fluid, taking advantage of the lighter Sunday morning traffic.

No problem, apart from me trying to drive with engine braking and the brakes as backup, which I don’t normally do and aren’t good at.

Best guesses at this time are still boiling brake fluid and/or failing master cylinder, with the former unfortunately less likely, given the amount of rusty sludge that came out of the bottom of the brake fluid reservoir. I suppose new fluid might buy a failing MC some time, but I’ll have to look into sourcing a replacement or a rebuild kit.

Unfortunately, it looks like mismatching of replacement MC’s is a problem for Charade G10 (which the Skywing seems to mostly be) owners in Europe. I suspect replacement parts are for the G11 and are slightly different, as seemed to be the case with my replacement brake hose.

Incidentally I made myself a simple brake-pedal-holder-downer thingy with a bit of aluminium channel shelf support notched for a rope at one end. Stick goes through the steering wheel onto the brake pedal, rope is tied with a clove hitch on the steering wheel rim. If you used bungee cord, or hung a weight on the end of the stick, you could probably get more brake pedal travel when you opened the bleed nipple and the bleed job would go quicker, but then you’d need a depth stop to avoid master cylinder seal damage.

I tried using a Taiwanese girl for this purpose (and have used a Scottish girl in the past) but the stick is simpler, more reliable, and much cheaper.

18

Embarrasing pictures :blush:

Above is shiny new brake pipe at full (static) lock, which isn’t quite full lock because there’s some backlash from tyre torsion. Not quite so worried about it now, since it doesn’t seem to be touching anything at either end of its travel (the last time was wheels off on stands). I’ll have to check it again dynamically though.

Whats that orange plastic ring supposed to be for?

Bit more worried about this one though. Though the core is intact it looks pretty bad at full lock, so I’ll just replace it with another G11 hose for now, even if it is a bit long.

Feelthie fluid. From left to right, rear brake bleed, front brake bleed, and a sample (I spilled most of it) of the sludge from the bottom of the master cylinder reservoir.

Obviously I should have changed this a long time ago. No excuse, but I do wonder if, the last time it was changed by a pro, they de-sludged the master cylinder reservoir. If not, it perhaps suggests y’all should consider checking this yourself, even if you normally get this stuff done by someone else.

19

Really, you should change cider brands.

20

Yeh, I think that stuffs probably heavily sweetened for the Taiwan market. GF buys it. I reckon diabetes will get her before the booze does.