306Diesel. Cam belt slipped & brakes lost

If it's slipped and lost timing and if it hasn't put a valve through a piston, then you've most likely lost the valve timing which would make any engine lose power. Dunno about the servo though, not on diesels.

It is possible that the timing belt has slipped one tooth. I had that happen when my alternator belt broke at 70mph on the M-way and a piece of it got between the timing belt and the crankshaft pulley. It sounded like a box of spanners and couldn't pull the skin off a rice pudding but still went.

I don't know how the vacuum pump is driven on the HDi engine, on my old 205 it was belt driven off the oposite end of the camshaft to the timing belt.

Hi,

From 1991 or so, without power steering, the vacuum pump is camshaft-driven. It's the same with HDis, whatever they have PAS or not : camshaft driven (direct drive, no belt). A lost of servo involving the pump could be a crack in the pipe (there's only one on these pumps), or a leak / slight oil level drop in the engine (but I can't imagine it to happen without lighting the oil pressure light).

HTH,

-- G.T

If it's direct drive, not working properly and rattling then maybe the drive is stuffed or the pump is coming loose or otherwise.

A drop in engine oil level wouldn't cause loss of servo.

Either the pump isn't being driven, or the pump is U/S, or there's a leak.

Steve

Hi,

In fact, I wrote this one 'cause when I asked my local mechanic why the pump only had 1 pipe instead of 2 for older, cam-driven pumps, he told me it was the oil movement which caused the vacuum into the pump. Perhaps I didn't get it the right way.

It cannot not being driven. Leak, worn pump, cracked pipe from pump to servo, or servo membrane cracked are the only suspects I see. The fact it's simutaneous with the cambelt incident is a bit amazing to me, perhaps just some bad luck.

Regards,

-- G.T

Actually GT, the drive can fail.

My 306TD suffered a sheared drive to the vacuum pump - it's a good job the cambelt was in good order because I feel a weak belt would have suffered lost teeth as a result of the sudden extra load.

At the time I had a Chrysler 440cid (big block - very heavy) engine in the boot and was slowing down for the pay station on the M6 toll, I rolled past the lady and had reverse back up. She joked and said I was trying to avoid paying!

I fitted one from an old ZX engine - different fittings, but with some vacuum hose and clips I soon had it working fine.

Julian.

Hi,

I stand corrected.

Regards,

-- G.T

Got the car back from the garage today.

Here is what the problems were;

The alternator belt had shredded (but not snapped completely) and become dragged into the Cam belt, causing it to slip and buggereing up the timing.

At the same time, whether by bad luck, coincidence, or because it was on the verge of failing anyway, the Vacuum Pump, which is driven off the cam belt I understand from the mechanic, failed.

The alternator belt tensioner also had to be replaced. This is the second alternator belt I have had go, and both times they have caused the Cam Belt to shift.

JB

It gets wedged between the pulley and cover and flails around ripping and smashing the cover - next is the cambelt.

Fsucking poly V belts - whatever was wrong with an old fashioned normal belt!

Julian

What u got the v belt cant you fit a flat belt to it or not, they have problems if not tight.make a noise like you got a bird under the bonnet,untill it is warm then i think its dead because it goes very quite,