Another case of chocolate cam

[doski]

Had my pd150 a few days now only done 150 miles In it and after a spirited drive I was cruising through town in second .CHUG CHUG CHUG CHUG then it hit me sounded like a canal barge after shifting down to 1st and the dreaded cam wear was apparent.

Has done 156k with FSH and many motorway miles but took off the can cover (egr is a b*tch) and the lobes have scored and there's a chunk out of the peice that sits on the roller 3rd from left.

So rang a garage to price me up a camshaft kit, cambelt kit and a service after.

Is there anything else I should get changed and how much should it be ?

 

[virdi]

The followers

 

[somersetdub]

That sounds like a very sudden change.. If it was ok and suddenly started chugging... Surely cam wear is something that would progressively get worse and cause a gradual decline in performance and economy?
I'm sure the cam is worn, but is that definitely what is causing those symptoms?


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[Muttley]

The usual failure is that the exhaust cam wears through the cam follower and when that finally breaks, you get the problems.

This is almost always down to lubrication failure, not using the right oil at some stage in the car's life. One or two services with poor lube and the hardening wears through.

It's never the PD cam, as that has roller followers, but because the single camshaft was redesigned to have an extra set of cams, the inlet and exhaust cams were narrowed, and in the case of the exhaust cams it was just a step too far. Proper lube will keep things going, but the wrong oil is fatal in the end.

The cam and followers will be worn, so both need to be replaced (not the PD followers though). You may well also have to change the exhaust valve under the broken follower.

 

[doski]

The usual failure is that the exhaust cam wears through the cam follower and when that finally breaks, you get the problems.

This is almost always down to lubrication failure, not using the right oil at some stage in the car's life. One or two services with poor lube and the hardening wears through.

It's never the PD cam, as that has roller followers, but because the single camshaft was redesigned to have an extra set of cams, the inlet and exhaust cams were narrowed, and in the case of the exhaust cams it was just a step too far. Proper lube will keep things going, but the wrong oil is fatal in the end.

The cam and followers will be worn, so both need to be replaced (not the PD followers though). You may well also have to change the exhaust valve under the broken follower.

Sorry what do you mean by not pd followers?

 

[Muttley]

The camshaft on the PD engine has three sets of cam lobes and three sets of cam followers. There are the usual inlet and exhaust valve lobes plus a third set which perform the pumping action for the Pumpe Düse injectors. These PD lobes have a very sharp lift where the injection stroke is performed, and so have rollers on the cam followers. These don't usually wear like the other followers, although if there has been damage sufficient to break pieces off the valve mechanism then those bits may have caused secondary damage...

 

[doski]

The camshaft on the PD engine has three sets of cam lobes and three sets of cam followers. There are the usual inlet and exhaust valve lobes plus a third set which perform the pumping action for the Pumpe Düse injectors. These PD lobes have a very sharp lift where the injection stroke is performed, and so have rollers on the cam followers. These don't usually wear like the other followers, although if there has been damage sufficient to break pieces off the valve mechanism then those bits may have caused secondary damage...

thanks for the info I dont have the 12 corner 10mm peice to take the rockers off and I dont want to spend money on tools if im not doing the work so i'll wait for the garage to inform me.

only thing that worries me is the chunk missing on the cam isnt on a lobe but is above one of the valves so maybe one's gone through and hit the cam there.

 

[Muttley]

I've found a page from the myturbodiesel forum that has some good pictures and explanation of this problem.

http://www.myturbodiesel.com/wiki/camshaft-lobe-wear-inspection-and-replacement-on-tdi-pd-engine/

And another nice pic, from a Norton motorcycle forum showing the wide PD lobe with its roller rocker on top and the exhaust and inlet cam lobes on either side, very much narrower.

http://s1040.photobucket.com/user/gsx800ho/media/VW stuff/TDI_PD_Cam1_zpsf93981c8.jpg.html

 

[doski]

And another nice pic, from a Norton motorcycle forum showing the wide PD lobe with its roller rocker on top and the exhaust and inlet cam lobes on either side, very much narrower.

in the picture of the cam (bottom link) mine has a chunk out of the cam where the green arrow is pointing?

As said before though i'l have to wait and see what the garage says as I dont have the tools or time at present