Red Dust Around Cam Pully

[Dave-G]

My regular mobile mechanic removed my cambelt cover in preparation for the belt change & found a "red-rust-dust" inside. It seems to be mostly confined to the upper area,directly around the cam pully, any ideers? He's left it for the day in order to get the latest belt-change book before proceeding any further (difficult to get one on sunday's). In case this sounds as though he's inept,it's been a while since he worked for me and forgot that i now have a post 2k gal,rather than my old SEAT

Edited November 9, 2003 by Dave-G

[Guest SA Intruder]

Very peculiar.

 

Must have done >150 cam belts over the last 20 yrs, never seen that.

 

As a suggestion, the cambelt runs "clockwise" and the last thing before the cam sprocket is the tensioner. Perhaps the tensioner is on its way out, and whatever is wearing is being picked up by the belt and once it gets into the 180 turn round the cam sprocket, it is being flung off.

 

I would be tempted to check all the rotating parts within the cam belt run for wear carefully. OR MORE LIKELY:

 

the other thing to check is the cam sprocket itself - it has a vibration damper within it now. This is made of a nitrile compound, and is either black, grey or red. It sounds like it may well be dying.

 

Another check point...?

 

Let us know what is found - !

[Dave-G]

Thanks S A. I've been hearing a chuffing noise from the engine at idle if i stand near the bonnet. this is partly why i wanted the belt and tensioner changed ahead of schedule.the previous owners [an airline company] did their own in house servicing to ford spec[apparantly],they showed a cambelt change @ 40k but no mention of tensioner is made!...I thought they went together? The specified mileage for change on april 2k build is 60k, It changed to 40k with the intro of 3yr wty. edit; changed the belt and tensioner,both looked fine. Also found that the alloy saddle clamp holding the steel pipe to the turbo has a crack in it, across it's centre. It still locates the pipe firmly so I'll leave it be for now

[Guest T120]

Dave-G

Did you find out what caused the red dust?

[Dave-G]

Well, I aint found out for sure,but thanks to S A i searched nitrile and a few other sites. Nitrile is highly resistant to air/oil/water/abrasion/temperature etc, which suggests a clutch/friction/grab function. the part of the pully that holds the belt teeth is bolted over the actual pully(having smooth pollished sides about 1" deep) via slotted holes that allow for adjustment of perhaps 1 belt tooth,and or timing. It's a sort of TOP HAT over the actual pully! Camshafts apparantly have massive harmonic vibrations that can cause metal fatigue. Although the "hat" is bolted to the pully, I assume the layers of nitrile material somehow damp the lateral vibrations being transmitted elsewhere by the belt. I aint an engineer,but it seems feasible to me, and i can assume that the dust is a result of flexing to absorb those vibes'.....which suggest it's working correctly. Given that this sort of maintenance is mainly confined to main dealers(the gal is only 3yr old) us mere mortal private users wont have discoverred it yet? Edit; In addition to the normal functions of a camshaft, these "pumpe-duse"? engines also employ the camsaft to inject the fuel(I believe) possibly producing even more harmonics than usual. OR maybe it's to damp belt bounce to the camshaft? I'm off to search "pumpe duse" next Another edit: Hmm, It seems the camshaft does inject the fuel, AT ABOUT 30,000 psi.............and explains why we dint see an injection pump!

Edited November 13, 2003 by Dave-G

[Guest Andyjflet]

Wow

Your pictures are very clear, much better than a Haynes Manual !!

 

Seriously though, maybe we could start a section with pictures of basic/ common jobs we can do on the galaxy , our very own Haynes manual.

 

Which digital camera did you use by the way ?

[Dave-G]

For Andy.. a fuji finepix a204, set at the smallest size and quality it will allow, to minimise time loading this page. However i think there's probably another section of this forum for "off subject stuff"

[Dave-G]

UPDATE: I have now "slipped in the back" of local ford/vw/seat dealerships for a word direct with their mechanics, rather than service reception pen-pushers. The general opinion is they've all seen it,manufacturers seen it,nobody knows for sure, dont worry 'bout it, never caused a prob[yet]