Car (van!) question

[andy230]

hello all,

and yes, its about brakes (quiet at the back, smudge!)

Or at least I think it is.   An under-bonnet noise from the wagon (LDV400 2.5 TD Pug engine- very good I reckon) prompted investigation.

Noise like a leaking header pipe, like a kind of pfft-pfft-pfft under load.  I thought header manifold or possibly head gasket...

But found its from the vacuum pump at the front of the motor.  Can anyone advise

1.  What it does (vacuum for the brake servo, right??)
2. How does it work?
3. Why has it suddenly go a bit noisier (weekend away at snetterton)
4. Implications?  Noisier itself doesn't bother me.  Safety and expense do!

Any ideas?  Not a lot of info in the LDV e-manual I have.  Cheers

a

[Steve H]

Pump is for brake servo, is the pump belt driven or on the end of the camshaft ?.
If belt driven then chances are it is the diaphragm type pump. These have a simple rubber diaphragm which does the pumping, its also very expensive to replace (or were some years back). Mine failed slowly, initialy the brakes would go hard when check braking, then after a while it wouldnt work at all.
The noise could just be a duff bearing, noisy belt, if its not the diaphragm type then it may need oiling. The pumps that sit on the end of the camshaft are fed oil from the cam.
I would drive the van and try pumping the brakes lightly, if its duff the pump will struggle to keep up with the servo constantly evacuating itself. Heavy braking doesnt have the same effect.
Most of the above comes from experience of the Peugeot/Citroen 1.9XUD engine. I would imagine the designs are related, others may know otherwise.

[Steve H]

Are you sure its not just a belt that needs adjusting. My auxiliary belt twitters if its not tight enough.

[guest146]

Andy

The Vac pumps on those are a bit troublsome. Its juls like a small crank with a piston on in and a couple of simple valves. They  have a bung on the end for initial lubrication but still dont last long. I have a feeling I have on in my spares box at work with worn holes but may work.Will have a look. May be able to copy you a  CD Manual if you need one.
Ken

PS How did you race go?

[andy230]

Hello all,

Thanks for the info.  I am pretty certain its not the belt needing tightening, the pfft-pfft noise would suggest that whatever needs to turn is actually turning.

Will check your braking test steve, thanks.

Ken, thanks for the offer of a possible spare, that would be good, and maybe the way to go if its on its way out.

Cant find any on ebay, but you can see it (belt driven) on the top/front of this lump:

http://cgi.ebay.co.uk/LDV-Convoy-400-1996-Peugeot-2-5-engine-and-gearbox_W0QQitemZ230221921609QQihZ013QQcategoryZ108856QQrdZ1QQssPageNameZWD1VQQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247

I will see how it goes.  Finally, any user-servicable parts inside??  From the way it appears pressed together I am assuming not?

Cheers

a

ps.  Ken.  Snetterton went ok.  Still not fast enough, but finsihsed one race.  Definate improvements to come!  Little write up:

www.team-thumper.blogspot.com

[guest146]

You would be lucky to find one on ebay as they are often failing.You may try topping back up with oil through the end bung but if its used it once it wount last long. I had lent my spare to someone but he is supposed to be bringing it back so if you stuck Shout.

Ken