Dephaser Pulley?

[Soot1e]

To me this looks like an inlet pulley stuck on the end off the camshaft, except the centre is made of some kind of plastic. Is there some sort of mechanism or clutch inside that varies the VVT. Or maybe I'm looking at the wrong pulley.

 

[Fred@BTM]

there's no plastic on a dephaser son!

pics

 

[biojo]

the pully to rear of engine is the zorst one just looks like a normal pully, the dephaser has a solid center

http://im4.ebidst.com/upload_big/9/2/8/1233691232-23253-0.jpg

 

[biojo]

fred do u think hes onabout the end caps , wrong side of engine?

 

[Soot1e]

the pully to rear of engine is the zorst one just looks like a normal pully, the dephaser has a solid center

http://im4.ebidst.com/upload_big/9/2/8/1233691232-23253-0.jpg

This is the one. It's not all metal in the centre is it. Why isn't it the same construction as the exhaust pulley.

 

[Fred@BTM]

the pully to rear of engine is the zorst one just looks like a normal pully, the dephaser has a solid center

http://im4.ebidst.com/upload_big/9/2/8/1233691232-23253-0.jpg

that's not a 172 dephaser, that's off a K4M by the look of it

 

[Soot1e]

It looks like that but is a reddish brown colour.

 

[Fred@BTM]

dephaser on the right

 

[Christopher]

They get very rattly on their way out.

 

[Soot1e]

Yep, so why is it different to the exhaust pulley construction and why do some people have more problems with this pulley than the exhaust one.

 

[Fred@BTM]

the dephaser pulley is the main part of the VVT system, its full of oil and works via a 12v switch that allows oil to flow into the pulley (this is in simple terms BTW)

when oil flows in, the pulley is advanced (advancing the timing)

 

[Soot1e]

Thanks Fred, I understand it better now.

 

[J444HN P]

So how does it end up failing?

What stops doing what to make the horrid noise?

 

[sideways danny]

it's basically got a spring inside that makes it return to a retarded position when the soledoin shuts and cuts off the oil pressure, the spring loosens/breaks/weakens and the pulley slops about a little

 

[Cookson]

and its a cambelt job to repair it?

 

[biojo]

when it fails they become loud and rattle. engine sounds bit like a diesel at times.

If it needs replacing , you have to take all cam belt aux belt off, so as yer paying for all that to come off 4-5 hours labour if i remember correctly, its recomended you replace both belts / kits.

 

[Soot1e]

I'm guessing that using the correct oil helps in preserving the pulley and preventing dirt blocking the mechanism.

 

[Christopher]

It'll prolong it's life, but they all fail.