Possible Camshaft issue

[Paul1b]

Hi Guys,

I have a 2007 Passat 1.9tdi (105). A rattling sound at high revs from the camshaft area persisted about 6 weeks ago. I took it to the mechanic and the camshaft and related parts were replaced. The problem then arose again and the mechanic replaced the rockers on the injectors. After 200km on this fix the nosie returned worse than ever. The car has lost about 70% power and is belching out black smoke. I took it to another mechanic as I am away from home and said the camshaft and cups were badly worn.

I trust the mechanic that new parts went in. Any ideas on what may have caused sped up ware of the shaft? The mechanic also said that it seemed to be lubricated enough. Thanks in advance. Paul

[DMitch16]

Hi Guys,

I have a 2007 Passat 1.9tdi (105). A rattling sound at high revs from the camshaft area persisted about 6 weeks ago. I took it to the mechanic and the camshaft and related parts were replaced. The problem then arose again and the mechanic replaced the rockers on the injectors. After 200km on this fix the nosie returned worse than ever. The car has lost about 70% power and is belching out black smoke. I took it to another mechanic as I am away from home and said the camshaft and cups were badly worn.

I trust the mechanic that new parts went in. Any ideas on what may have caused sped up ware of the shaft? The mechanic also said that it seemed to be lubricated enough. Thanks in advance. Paul

Sounds like the camshaft and associated parts were not replaced and a quick fix performed to temporarily quieten the noise. Camshafts and hydraulic tappet cups would not wear to a bad state in 200km with adequate lubrication.

[Paul1b]

Thanks for the reply DMitch16. My worst fear unfortunately.

[DMitch16]

Thanks for the reply DMitch16. My worst fear unfortunately.

Would be a shame if the original work was not done but there are still a few cowboy mechanics around. Changing camshaft and tappets is not that pricy but is a moderately lengthy job on a Passat but the 8 valve motors do suffer from tappet wear, it is a known issue that cam lobes can eventually wear holes in the top of them. Improved versions are available but driving the car in a bad state is not advisable as it will cause further damage. A cam kit with most of the other parts included is around £130 plus labour and care should be taken with each step of the process with adequate cleaning and correct fitting processes. Cam shells need to be fitted to completely dry, oil and dirt free journals and pre lubricated on the facing side along with the cam journals themselves. Fitting them to oily surfaces will quickly destroy the work done as they will simply move and cause major damage. Rocker clearance also needs to be set correctly to reduce engine noise, improve running and fuel economy thus prolonging injector life.

If it is a BXE engine I'd have a competent mechanic check the crank and bearings also as they have a reputation of 'shaking a leg' which means the bearings fail, jam and chuck a connecting rod out of the engine often through the bell housing or block. Happens with a bang and a large puddle of oil on the floor. Safer to make sure the noise is definitely top end and not the bottom but if your 2nd mechanic says there's top end damage or wear then that is most likely why the engine is so noisy. Doesn't take much to get the cam cover off to show you what's worn.

Perhaps someone can do that for you?

[Crasher]

Possibly he may have only changed the lifters and a worn cam will eat those for breakfast, also he should have replaced the rocker arms anyway with the cam as not doing so will invalidate the cams warranty but it is a chance many people take as the rockers are so expensive.

[DMitch16]

Especially if using the softer version of the lifters...until I pulled a worn camshaft from a 1.9 tdi, I had not realised how sharp the edges become when very worn. Perhaps 200km is enough for it to start to chew new lifters again to the point of noisiness, if still the original camshaft.

[Crasher]

Yes, the edges are like a scalpel blade! The rocker arm lobes seem to wear differently