Q: I have a problem with the engine and probably it is more serious than I thought. When the engine is at the lowest rpms (when the rpms are high I cannot identify the noise), I can hear a click-click that comes from the engine head. I have to note here that all these started because I had a little oil leakage from the rocker cover gasket and I tried to tight more the rocker cover screws. When I did that the oil leakage stopped but that noise became noticeable. As much as I tight the rocker cover screws the noise became stronger. In Athens where I was for holiday at Christmas time they told me that this noise is the result of worn-out valves but when I told them that I replaced these a year before, they answer me that maybe are worn-out the parts of the engine-head that the valve’s are running into (sorry I don’t know the word in English ). The screws of the rocker cover are on the cam’s support and when I tighten the screws these are pushed up so the cam’s starts to move etc. Do you know any other cases like that in the past? What you thing I have to do?
- Tassos -, tassos@viva-lancia.com

A: The point about the engine noise is potentially a serious one even if I am not sure I fully understand your description of the problem. Let me give you some general ideas.

1. The rocker cover should NEVER be tightened too much. The rule is to compress gently and just enough the gaskets which have been kept in place by applying a small amount of adhesive or instant gasket paste.
2. Unless you remove the rocker cover you will not see anything and the chances are that you will have to remove the cylinder head as well. To start, check the timing chain for tension, the condition of the timing chain tensioner and the valve timing because if the camshafts have slipped one tooth of the timing chain you get a noise of the valves hitting lightly the piston. This typically occurs on cylinder #2 but other cylinders are not immune to this.
3. One (or more) engine valve may be burnt or the valve seat ruined (this is usually a result of running without lead in the fuel). This becomes apparent only if you remove the cylinder head but a very rough indication can come by doing a compression test with a suitable instrument.
4. It is a fact that for some time there have been on sale Fulvia engine valves clearly sub-standard. They were not from Lancia but after-market replacements. These valves tend to break (with consequent engine disaster) and for some time before breaking they produce strange ticking noises. The only solution is to inspect the valves and replace them.

In summary then, if you are convinced that the engine valve timing is correct and there are no obvious faults with the camshafts, rockers and timing sprockets, you must remove the cylinder head to make further investigation. I am sorry I cannot be more precise and helpful but without hearing a noise it is difficult to judge. I know of Fulvia engines which have been destroyed by timing chain failure or valve problems.
- Andrea -

The story continues. The reply of Tassos was received garbled, but here is Andrea's reply to that.

As far as your engine problems are concerned, if the valve timing is correct, the noise can only come from the valves because the noise of a worn timing chain is a rattling, whirring noise. A badly worn chain will jump off under strong acceleration, so take care when starting off. Soak the timing chain for 24h in clean engine oil before fitting it. Of course, to fit it easily you undo the bolt pressing the spring of the tensioner, link the new chain to the old one and you turn manually the engine crankshaft pulley until the new one has fully replaced the old one which is then removed. Then you have the long game of retiming the valves. Some axial movement of the camshafts is normal.

Reboring the engine cylinders will usually mean to increase their diameter by 0.2-0.6 mm. This has no relevance to the head gasket size. It is far more important to follow the correct bolt tightening sequence and to use a high quality torque wrench because the torque is small and many tools overestimate the value. To ensure long lasting results after reboring (which is required only after amazing high usage: probably near 300,000 KM if the engine has always been serviced and the top end overhauled) the engine cylinders need fine honing because they should acquire a surface finish very slightly crossed to improve compression and avoid oil burning. Piston rings must be mounted with gaps at 180 degrees for the same purpose. If you have to renew the valve seats you might consider fitting new ones which are compatible with lead-free petrol (see Omicron for example). It is vital to use a truly professional engine reconditioning shop because if the seats are fitted slightly slanted there will be soon valve problems (I have seen such bad examples). - Andrea -