Sevenman's TVR (was SAAB) Blog

June 23, 2006

I have brakes!

Filed under: Saab — Administrator @ 5:04 am

I now have servo-assisted brakes and it is a wonderful thing.

After my local garage dropped the pipe off last night I fitted it and went for a successful test drive.

It looks like the fault was the acid-coroded one-way valve.

Here is a pic of the old pipe :

and a closeup of the damaged valve :

I did some blowing tests on this pipe. From the servo end you could blow but not suck, as it should be, but from the manifold end you could do both as air was escaping from the valve.

Here is the new pipe :

and a closeup of the label if you need to order one for any reason :

Below you can see the new shiny connector on the intake manifold :

and the pipe fitted, with the valve near the Y-piece in the vacuum pipes :

Finally, here is a photo showing where the pipe goes into the servo – it is awkward to see, and awkward to get to :

The servo pipe is coming in from the bottom left, and has a push-fit just left of where you can see “SAAB” in white writing.

I am happy now my brakes work, and at £20 this is one of the cheapest problems I have had. Hopefully my new battery will avoid such issues in future.

June 19, 2006

No servo assistance

Filed under: Saab — Administrator @ 9:30 am

Visitied my local garage on Friday.

They agreeed that servo assistance has failed.

Following the servo vacuum pipe from the manifold reveals that the one-way valve is located exactly where battery acid spray wrecked my vacuum pipes. Hopefully replacing this pipe and valve will fix the problem.

I also fitted a new battery at a cost of £48. Perhaps this one will contain its acid. Did a few voltage checks with the engine idling. About 13.8 volts under normal load dropping to 13.6v with air-con and others loads running. Seems ok.

June 15, 2006

warning light test

Filed under: Saab — Administrator @ 6:41 am

I hadn’t thought about the testing the warning light bulbs so have been outside turning the ignition on and off.

With ignition on, the display in the bottom right hand corner comes up with the ABS, Battery and Handbrake warnings. After a second the ABS warning disapears.

Some way right of the handbrake warning should be the Brake warning – this light does not come on then the ignition is turned on.

I guess this could mean the bulb has failed, and wouldn’t tell me if there was a servo problem.

June 14, 2006

more brake testing

Filed under: Saab — Administrator @ 5:53 pm

I have done some more testing of the servo.

Before starting the car I pressed the pedal numerous times – it was fairly hard and may have become more so.

I then started the car while pressing the pedal and it did indeed move downwards slightly.

I drove the car for a bit and the braking was, as before, abysmal.

Upon reaching the top of my straight, quiet and slightly downhill sloping road I dropped my speed and turned the engine off. I did repeated brake application down the road and the braking got no worse or better. Then restarted the engine, again pedal dropped, and again braking stayed just as bad.

The pipes look ok, assuming these are the right pipes, and I can only see the top of them.

June 13, 2006

Finding out more

Filed under: Saab — Administrator @ 9:24 pm

Visited my local autoparts store who can provide a FIAMM battery for £48 – should do the job but they have none in until Friday.

As I drove home I had an idea about my brake problem. Upon reaching my road which slopes slightly downhill I slowed right down and turned the engine off. As I coasted I used the brakes and found the stopping power was very similar to when I had the engine running.

Restarted engine and nothing changed.

Perhaps the pads/disks are fine and the problem is the brake servo. I have no idea how these work but maybe it started to fail on the track when I lost the ability to brake hard and then failed completely a couple of days later.

When I lost brake power on the track it was because I couldn;t push hard enough to stop rather than the pedal travelling to the floor which I believe is characteristic of brake fade – feel free to add a comment if you know.

For an obvious brake check I checked the engine bay fuse box that controls ABS systems. This sits under my strut brace and it took lots of effort to get the lid off. Fuses were then, and then it took ages and lots of effort to get the lid back on. This is the only part for which the strut brace makes access awkward.

brake communications

Filed under: Saab — Administrator @ 7:03 am

I have been in touch with technical support at EBC brakes regarding their Redstuff pads. Here is the information I received from a few e-mails.

Redstuff pads are unsuitable for trackdays and they do not recommend it

They only recommend yellowstuff for trackdays

And directed me to www.ebcbrakes.com – where it did indeed say “Fast Road Use” under RedStuff pads.

They also said Redstuff is suitable for road use only

Regarding my glazed pad problem, they said the pads may come back when the existing surface which may be carbonised is removed with normal driving over about 500-1000 miles.

However this won’t be fun. I drove my girlfriends Mondeo last night and we had some unusually sharp stops as I got used to a responsive brake pedal. I don’t want to drive 1000 mils like this…

Also got some part numbers for the 9000 :

Yellowstuff:

front pads dp4751

rear pads dp4635

Finally I asked about the possibility of having yellowstuff on the front and keeping redstuff on the rear and was adivsed not to mix the compounds as it is possible but it may not be perfectly safe

Asking about whether to go for grooved or plain disks I wqas told I may be better on the track with grooved at extreme braking levels but may be better on the road with plain discs

The final bit of advice was that I could try and resurface the existing pads with a file to remove any burnt surface compound.

I am now inclined to try and get the surface taken off these pads. If I buy a new set it will be expensive since I am likely to go for Yellowstuff pads and grooved disks, and it would also be the 3rd complete set of disks and pads in 2 1/2 years.

Just had a look at the battery. From the handbook I need a 60 or 62 Amp hour battery to replace it. Current battery dimensions are 24cm long, 17.5cm wide and 19cm high. Will be calling a few suppliers today to get prices.

June 12, 2006

Brake and battery problems

Filed under: Saab — Administrator @ 12:58 pm

The car is suffering from the trackday.

Brakes first :

As stated in the previous post they faded a bit on the track. From what I remember they were ok on the drive home.

However now they have seriously limited stopping power. I can’t get the wheels to lock, and even gentle stops require plenty of force.

I am not happy driving the car but have had to use it a bit and it isn’t fun.

I am not sure what’s wrong but it could be related to the overheating of the pads on the track. Either way I either need to fix it or change pads.

I am not sure whether I can keep the disks and put my DS2500 pads back on or need to change the disks as well again…

I am sure the last set of front disks I took off were nice and smooth. This time the fronts have noticable grooves that I can feel by running my finger along the disk. The rears are still smooth. This probably isn’t a good thing for the front disks. Hopefully I haven’t damaged the rears – handbrake still seems ok, so maybe I only need to change the fronts.

These trackdays cost me more in brakes than they do in entry fees.

Secondly the battery :

This battery has had a hard life – being pulled down to 1.2V when the alternator failed, and spraying some acid in the battery compartment which coroded vacuum lines.

Well, it did it again. I noticed some battery leakage at the trackday and cleaned it up. However when on a long drive (with dodgy brakes) I noticed the boost gauge wasn’t going as high as usual when I put my foot down. I initially though “not another APC valve” but when looking under the bonnet found the following damage done – near the battery where the vacuum pipes from manifold and dump valve meet at a Y piece to the in-dash gauge.

Removing the pipe at the manifold and blowing down it highlights all the air escaping there. Dump valve still seems to be dumping, but the boost gauge does very little.

So now my shopping list is :

1) Brakes
2) Battery

Luckily I have lots of spare vacuum hose so will change that soon.

June 1, 2006

More photos

Filed under: Saab — Administrator @ 10:43 am

A few more photos from the trackday, taken by /john and Scaero

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