Is This Terminal - Penultimate Chapter.

rory_perrett · Unread post by **rory_perrett** » 11 Jun 2006, 23:45

Quick recap - Xantia 2.1td poor running, loss of power black smoke excessive noise with then got dramatically worse.

Diagnosis -part of the auxiliary belt that had stripped off had managed to get into the timing belt cover causing the belt to jump on the camshaft pulley by 1 and then 2 teeth, making the timing on the camshaft late.

I have now got the head off and it looks like "I've got away with it" I'm trying to decide if there are signs of contact between the exhaust valve and the piston on cylinders 1, 2 and 3. It is most obvious on 1 (although for some reason it is accentuated by the flash and is more obvious on 2 and especially 3 in the photo than in reality).

There appears to be no mechanical damage to the piston or valve face only the absence of carbon deposits.

Does this look normal?

PS First attempt at attaching photos so please forgive me if it doesn't work.

citronut · Unread post by **citronut** » 12 Jun 2006, 20:08

with the cam either removed or just rotated so the valves in question completly closed and the head on its side pour some petrol into the port on the upermost side of the head,and see how much runs out past the valves,this will show if the valve is seated properly,also is there any markes on top of the pistons,if any of the valves are even slightly bent and you put it back together it will in time burn the edge of said valve out
regards malcolm

Stewart(oily) · Unread post by **Stewart(oily)** » 12 Jun 2006, 20:12

I dont have experience of the 2.1 motors but I have repaired a number of the smaller 1.9 diesels after cambelt breakages and did find similar marking to the tops of the pistons, usually the camshaft is snapped into pieces and the cam bearing caps are broken too, in some cases even with this damage the valves were okay, otherwise I needed to replace valves and guides, though this was less common, in your position I think I would remove some valves and roll them along a flat surface to check for straightness, then congratulate myself on good luck

Stewart

rory_perrett · Unread post by **rory_perrett** » 13 Jun 2006, 15:25

Thanks guys, I guess it might not be the penultimte chapter. I think the exhaust valves will have to come out and be checked. As commented in a previous post, the 2.1 having hydraulic tappets along with the belt not actually breaking and my suspicion that it was initially only 1 tooth out and slipped a further tooth at low revs I'm going to be lucky.

As I plan to take this opportunity to do all things that are likely to need doing in the next 60k or so miles like waterpump, clutch etc, would hate to get it all back together and find it has to come out again!