Defender sounds like a kettle after I have turn the key OFF

[Baz2236]

Hi I have a strange problem with my truck once I have turned it off you can hear a hissing coming from the engine bay which get louder like them old kettles that whistle at the end.

I think its coming from the VAC pump or the servo if I disconnect the pipe that goes inbetween the two the noise stops if I press the brake pedal when the noise it happening it stops straight away.

The Brakes work ok for an old landrover but I want to sort out the problem before it gets worse and manifest into somthing serious.

Anyone got any Ideas

[Adam001]

Check the condition of the vac pipe (they perish) and the clips that secure the vac pipe (they are typically the old wire type, swap for a jubilee). The sound is air being sucked through a crack or under a hose tail at one of the ends, the sound is always there if it leaks, you can only hear it once the engine is off.

Chances are that'll be it, next check is the fitting at the servo, I've not had one out before but it's a clip in fitting, presumably with a O-ring at the base.

[Baz2236]

I will try that pipe tomorrow

[Snagger]

Defender servos can suffer fatigue cracks near the master cylinder mountings, so take a close look around those studs - you might need to take the master cylinder off the servo to do it properly, though you shouldn't need to disconnect the plumbing. A cracked servo could split all the way, which would cause the master cylinder to break loose completely, resulting in total brake failure, so check it carefully.

[Baz2236]

I replaced the pipe and put on new jubilee clips on either end issue is still there.

I had a quick look at servo but seems ok.

Is it ok the remove the nuts off the servo so I can slide the master cylinder out slightly to check.

Or shall i just bite the bullet and get a new servo is a disco servo the same as a 90 mine is a 86 if it makes a differnce.

[Aragorn]

can you pinpoint if the noise is coming from the servo or vac pump end of the pipe?

[Snagger]

I replaced the pipe and put on new jubilee clips on either end issue is still there.

I had a quick look at servo but seems ok.

Is it ok the remove the nuts off the servo so I can slide the master cylinder out slightly to check.

Or shall i just bite the bullet and get a new servo is a disco servo the same as a 90 mine is a 86 if it makes a differnce.

Yes, you can just do that for inspection. I don't think the Disco servo is the same, but I stand to be corrected.

[Baz2236]

I have pulled the MC out a little and can clearly hear the noise is now coming from the servo the rubber around the rod that comes out is split if i wobble it I can change the sound of the Hiss.

So new Servo time or can I get a repair kit.

does it have to be from an older 90 or would a newer defender one fit does anyone know before I spend hour looking on inter web

Thanks guys for your help. This forum is awesome for help and advice.

[Daan]

I had something similar when I first mot'd mine, but more like no brake servo at all. I turned out that there was no O-ring between the servo and the master cylinder. I fitted one from my box with old bits, it could well be faulty on yours. My servo is the 300 TDI age.

Daan

[Baz2236]

Hi Got a little bit further and throught I had fixed my issue by replacing the servo brakes were good very light pedal.

Went off roading this weekend first long trip with the new servo and I noticed through out the day and especially on the way home as approaching a round about I brake a little coast brake a little more then start brake hard my brakes get less and less efective until It feel I have no servo asistance and can bearly stop.

I swap the Vac pump today for another thinking it could be that but its still the same it seems the more I pump the worse my brakes get.

Have I been sold a Dud Servo you think or do I have another problem.

Baz