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Thumping noise and rattle

3.7K views 13 replies 6 participants last post by  G4V JW  
#1 ·
Hi
I have had a noise develop on my 54 2.5 174 with nearly 170k. The noise started about a thousand miles ago after it was serviced with the correct oil when the alternator pulley was changed. At tickover there is a kind of thumping noise which comes from the engine side when the pipe on the EGR is removed. At over 2k revs it changes to a tappety noise and gets worse the higher the revs. It also smokes on startup now like it has been sitting for a while. I have had a search and listed possible problems below.

Low oil pressure
camshaft/lifter wear
Injector seat wear
Cracked manifold

When I changed the pulley I also had the intake manifold off to clean it but did not replace the rubber gaskets as they looked Ok. Not sure if this would cause this noise if it was leaking? I also changed the glow plugs.

Can anyone tell me if any of the above would suit the noise it is making? Any help would be appreciated to save me pulling everything apart.

Thanks
 
#5 ·
Its not the camshaft that fails first its the bad design followers that fail and then wear the camshaft. As its a gear driven engine the camshaft is forced around by the gearing so will wear the top of the followers and then the camshaft lobes look like they have been hammered, its also a full time contact design and any lift or separation is bad for both. The followers go hard as the oil can't escape properly and in turn increases wear through friction, the 1.9 engine is the same but the camshaft is belt driven and has its own problems and is made of cream cheese I:
 
#6 ·
FYI, I had my top end completely rebuilt about 3 months ago. 2.5 AXD cam was worn but not too bad, buckets were worn but not all the way through. With new cam, followers, seals, injectors refurbed it now smokes quite badly on start up but only for a few seconds and sounds the same as it did before spending over a grand. I'm at a loss as to why, but sometimes you have to leave well alone until something lets go.
 
#9 ·
I have just spoke to Keith at AW engineering and he supplies a kit with a steel camshaft rather than the original early camshafts which he say's where to soft. I'm assuming the early cams were case hardened and the later cams are through hardened or the grade of steel was changed? Has anyone used a kit from AW and put some miles on it? I don't want to fit another cream cheese cam.