Jump to content

Brake booster crack


Recommended Posts

Hi, does anyone know if you can get a new brake booster as mine has split or cracked just by the two bolts (top & bottom) that bolt the master cylinder to the servo front unit, I've been told that this is a common problem with the servo units, so would assume that you can get hold of a new front servo unit?

Thanks.

Link to comment
Share on other sites

Very common problem even on 300Tdi Defenders built up till recently for export markets, I have seen a 2003 with a cracked servo unit. Forget a genuine one get an OEM one (I think they are Lucas) from Bearmach or somewhere similar, its half the price or less.

Link to comment
Share on other sites

Thanks for that, hopefully it will make the brakes better! or may be not!

It will make a huge difference, it is one of those things that develops gradually and you don't realise how bad the brakes are till you fix it :)

Also - try an emergency stop before and after, that is when it makes the most difference!

Link to comment
Share on other sites

And I thought the brake servo on Defenders gave no problems at all. Just the export models, you reckon?

All 300Tdi's in my experience? :unsure:

They crack around the outside of the twin bolts about 1/2" from the bolt centres, we sell dozens of servo units and have done for years.

Link to comment
Share on other sites

And I'll try and find a pic of a typical one at work, though they mostly get dumped straight away

I'm guessing we noticed the first ones about five or six years ago, something like that, on the early 300Tdis - they usually go at about 5 years old.

Link to comment
Share on other sites

I asked Brian the boss yesterday and he seemed amazed as he has never changed one (as I thought). He has been in business since about 1999. We had a good laugh about the things that go wrong with Land Rovers, just when you think you have seen it all something new happens. For example we had a TD5 with a disintegrated small-end bearing the other day, and that is rather unusual I would say.

Link to comment
Share on other sites

And I'll try and find a pic of a typical one at work, though they mostly get dumped straight away

I'm guessing we noticed the first ones about five or six years ago, something like that, on the early 300Tdis - they usually go at about 5 years old.

Hi Bogmonster, I was just wondering if you had the pic's yet? Just to be sure, I can feel the cracks with my thumb nail but they are really hard to see!

Link to comment
Share on other sites

Hi Bogmonster, I was just wondering if you had the pic's yet? Just to be sure, I can feel the cracks with my thumb nail but they are really hard to see!

Sorry I forgot to go and check. Will try and remember to have a look later on - but we may not have any lying around, it isn't something we keep as it is no use for anything!

Link to comment
Share on other sites

Here you go Jim, with impeccable timing a cracked one came in today :)

post-33-1180986854_thumb.jpg

post-33-1180986871_thumb.jpg

They always go just where this one has, first tell tale is usually a bit of rust and after a while the crack opens up with the flexing of the servo unit.

This is a really bad one but any sort of crack means a loss of brake vacuum and braking effort - this vehicle felt fine until you tried to do an emergency stop and then you found the pedal didn't go down any more, locking the wheels was a bums-off-seats job :huh: twenty odd stone of me can do it but if it was a seven stone weakling or a diminutive lady driver it might be a different story! I'd also guess it pressurises the crankcase to some degree because I think the vacuum pump vents into the crankcase so if there is a vacuum leak it is pumping air into the engine, not a great idea really.

This is a 2003 model 300Tdi Defender by the way, so only four years old!

Link to comment
Share on other sites

Blimey, first time I've seen that, looks like a weak area of the vacuum casing pressing, to much flexing underbraking, glad my 110 has the older smallet /fatter servo :D

I am pretty sure that is what is the problem Ralph, basically just metal fatigue due to the casing flexing around the mountings.

Link to comment
Share on other sites

Reckon so, it must be thinner in that area due to the change in angles & the stresses imposed when pressed during manufacture.

wonder if any garage/dealer has mentioned this problem to LR, I'd class it as a fairly serious fault that should have a tech bulletin issued, if it was a part one my aircraft a serious defect report would be generated.

Link to comment
Share on other sites

Yeah but if your aircraft can't stop the consequences are more serious when it runs out of road at 200mph :)

If I had access to GTR I might well have just had a look and found that in fact LR do not have any technical bulletins at all on the subject. May be worth a mention...

Link to comment
Share on other sites

Yep, just a bit more serious.

I've looked in my Rave CD's [upto 2000] & can't find anything,

How many have you seen so far ?

I've been told its a very common problem but as it happens gradually no one notices until its that bad that they have to do something!

Link to comment
Share on other sites

Yep, just a bit more serious.

I've looked in my Rave CD's [upto 2000] & can't find anything,

How many have you seen so far ?

Having done some research to put accurate numbers on it, about 100 odd in the last five years. Which is quite a few in a place this size...

Link to comment
Share on other sites

  • 3 weeks later...

Thanks for the pics Steve. So out I go and examine 4 Defenders outside the office. (One is mine). No signs of a crack in any of them and they are all 95/96 models, at over 200k kms. But also no sign of any corrosion either, just pristine black paint. Is it possible that the rust makes the difference, maybe on the inside as well? The vacuum pump may let water vapour in or something like that? This does rather prove that although we are both 'south of the border' the weather conditions are completely different.

Maybe you could attack the next one with an angle grinder to see what it looks like inside?

ps come back global warming all is forgiven! It's cold by our standards here now, only 18c today and about 1c at night.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy