Scott.T

iTrader: (2)

I have noticed a very slow knocking noise occasionally occurring.

'When' is happens It is most noticable at idle, but it does increase with engine speed. However with head under bonnet you cannot hear it much above 2,500rpm due to engine noise.

It also seems to be on a luke warm engine i.e driven 3 miles then left to stand for 1/2 and hour. I have not 'Yet' noticed it from cold.

It's quite a heavy knock, but it is very slow. I would guess at idle (800rpm) the knock occurs about every 0.5 - 1 second. I cannot seem to locate the area it is coming from, other then 'under the bonnet'

I can't think of anything that would be geared down from the crank speed, so am a bit baffled.

After it happened this evening, I went back to the car 5-10mins later and restarted it to put it in the garage. The knock did not occur ????

P.S It's not the cambelt tensioner as I've had that done a couple of months ago. The noise fromthat was more of a fast tap rather then slow knock. MY00 UK Spec 25,000 miles

Turbo_Steve

Slight piston slap when engine is hot and bore clearances bigger?

Scott.T

iTrader: (2)

Nope not piston slap, as heard that on a mates MY98 and my old Cosworth.
The frequency is alot slower.

Have just read elsewhere that the water pump may run slower then the crank, so maybe that's a possibility.

Scott.T

iTrader: (2)

No noise this morning from cold when driven out of garage during the normal morning car shuffle on drive escapades.
No noise when re-started to leave for work.
No noise during the journey, with several traffic light halts.
No noise when at work in the car-park.

V.strange

The only thing I can think of at the moment is if the oil pickup funnel/baffle thing has dropped into the sump ???? and is being hit my the crank.

I have only really ever noticed this on my drive-way (so far). This points downhill slightly, so maybe the funnel/baffle thing (if it has fallen off) is at the front of the sump in this instance

Any more clues anyone ???

Scott.T

iTrader: (2)

Knocking started again, so ran it round to my mechanic.

Turns out to be the belt catching on one of the guides above one of the cam pulleys'
It has also caused the belt to get a few marks/nicks in it.

New belt and guides checked will feeler gauges seems to of cured it.

Big thanks to Vince at RDS for starting the job at 17:15 last night and giving me a call at 21:00 to say it's sorted....not many places will give you that sort of service (with a great Labour rate too).

Anyone in the Kent/Sussex area should really use this guy.......