Thread: Shuttle valve

Don't know if you need this

Originally Posted by stevo

I have a rovacomlite I think there may be a dealer in aussie their web address is www.rovacomlite.com

Same here, I bought it from Hardy (http://www.hardrange.com/) as I needed it quickly to re-enable my Disco. Great product, only had it about 2 weeks.

I'm thinking we should also have a Rovacom thread on the forum.

Originally Posted by BradM

Hi,
<snip>
As you guys already know you cannot even bleed to brakes (ABS) unit without opening the valves in it with the software.
<snip>

Not true - pressing the pedal will open the shuttle valves.

Testbook is used to operate the ABS pump to circulate fliud around the pump's circuit, and this can be achieved by temporarily replacing the pump relay with a jumper wire/switch.

there is also 8 solenoid valves 2 for each wheel I think test book also opens and closes these as well to get fluid through all the gallaries,there is 6 check valves,2 flow restrictors,2 damper chambers,2 expansion chambers,the return pump(sbs pump) and the shuttle valves which are moved by hydraulic pressure which in turn sends a signal via the shuttle valve switches.

From what I can gather from various sites the problem is with normal bleeding the brake fluid takes a easy path through the modulator leaving old fluid in the passages controlled by the 8 solenoid valves the gunk build up can lead to problems inside the modulator,but then there are alot of different theories out there

well I followed the test prodcedure out lined in the landrover bulletin
www.nettechy.com/LRabsBulletin.pdf well the first time I connected the multimeter it showed a open circuit so reconnected went for a run to the shops,the 3 amigoes were on after coming back from the shops the lights stayed off.

did the test again this time showed 3106 ohms (within spec's) when I started to apply the foot brake the readings started to drop then went to a open circuit state then would start to show a resistance before going to a open circuit state again.

So I would have to say the problem is inside the modulator,step 14 of the bulletin says if the value is out side of spec's replace the modulator this bulletin issue date was 28-10-04 which is before the shuttle valve kit was made avalible on the market due to alot of people kicking up a stink over the cost.

When I get the shuttle valve kit and pull the modulator to bits to clean every part and check the internal electrical connections as well,this will be one job where the cold beer will have to wait to many valves that could go back in the wrong way may end up having a jim beam after the job is complete

Every car we've fitted the shuttle valve kit here has had the same faults return. There's been around 10-15 done since the kit was made available.
If the car is under warranty, the ABS modulator gets replaced.

afraid mine is no longer in warranty and spending $100 instead of around $2500 has got to be worth trying did they change something in the later modulators or change the ecu software to stop this problem happening in the later models??

Wabco do not want nothing to do with this as some people have tryed to talk to them to be told to go away

See this thread - at the end.

http://forums.motorcars-ltd.com/show...6769#post66769

Originally Posted by gallagher

Since this last post there has been some extended discussion about the failures of the ABS modulator in the Disco II's. Seems the biggest culprit is the shuttle valve, and Rover came up with a couple of TSBs to address it.

To make a very long story short, there is a Service kit available to repair the shuttle valve in the ABS Modulator. But before you get a gooey thinking about how much money you're going to save hear this.

The procedure requires a bunch of testing with a meter, and 99% of the the modulator will have to be replaced anyway. And, if you open it up and there is oil present, they say to chunk it anyway!

Ron