thought water pump had gone but not

hi guys thought my water pump had gone yesterday(p38 diesel) i was driving to work and temp gauge went up higher than usual and there was a jankling noise coming from the engine (power steering went heavy and alternator fault flashed up)so turned it off and the noise sounded for a second or so then stopped started it up again noise was there and went quite turned off and it was there again for a second, even the aa diagnosed water pump i got it transported home and stripped the pump of today(yes i parted with blood on the viscous fan) and turns out the pump is fine impellor is still in place, bearing is ok ,ive checked the alternator,power steering pump tensioner and the idler roller and they all seem to run smooth and dont catch on anything, any ideas on what else i can check while im waiting for the new pump to turn up or is it likely to be more sinister and need a engine?

Hi

The fact that 3 of the systems that run from the auxiliary belt signalled a problem (water pump, pas and alternator) suggests that belt must be slipping. The fact that the noise continues for a second suggests that something is continuing to spin after the belt has stopped, again suggesting belt slippage.

How carefully have you checked the belt tensioner? It should be pressing fairly hard on the belt, I needed a piece of wood about 12" long to lever it away from the belt. Suspect the spring/damper unit, rather then the roller. Also check the bolt securing the spring/damper unit to the engine is tight. How loose is the belt on the idler roller (the one next to the alternator)? Can you slide it off? Anything more than a mm or two of sideways movement would suggest the tensioner is not doing its job properly.

HTH - unlikely to need a new engine I think given the symptoms you describe! Fingers crossed anyway......

Cheers

Jerry

Just a thought? Check the Woodruff Key on the crankshaft as a broken one might allow the pully to spin but not drive the pump which might explain the rise in temp?

if it was the woodruff key surely nothing would go round i can start it up and see everything is going round that is on the same belt

Could be viscous fan continuing to spin a little after engine is turned off

right guys just found out what has broke its the crankshaft vibration damper pulley has any one got one they what part with for beer tokens thanks