Technical Punto Non-FIRE 1372cc Tappets

[dukeboys]

Please see attached pics of my cam and two followers removed from my engine today. Im getting a noisy top end above 60mph hence the strip down.
These are from number 4 exhaust and number 6 inlet.
I have corresponding brown burn marks inside the respective follower holes inside the cam carrier on the front and back of the holes.

Also on the camshaft i have brown discolouring and some markings that run across the round end area on every lobe that suggests maybe that this part of each lobe is not getting any wear (a spare cam I have is shiny all around the lobe so one is right and the other must have something wrong with it fo show I just dont know whats normal wear) or could it possibly be heat discolouration from the valve clearance being too tight? Clearances not checked in 5 years.

Just wondering if the carrier and followers are original that makes them 17 years old and they are just worn too far. I have a much better condition cam carrier, cam and followers - thinking of putting these on and shim up from scratch......

Clearance on valve 4 was 0.45mm (should be 0.50mm +/- 0.05mm so in tolerance)
Clearance on valve 6 was 0.38 mm (should be 0.40mm " )
Havent a clue what this points to so any guidance would be appreciated.

 

[fingers99]

Please see attached pics of my cam and two followers removed from my engine today. Im getting a noisy top end above 60mph hence the strip down.

This is a worry in so far as a top end noise should occur at X revs, rather than X road speed. Maybe this isn't the tappets?

Also on the camshaft i have brown discolouring and some markings that run across the round end area on every lobe that suggests maybe that this part of each lobe is not getting any wear

Think of the opening lobe of a cam as the sticky out bit. The round (opposite) end is the base circle (where you take all the measurements for valve clearance). You can only take measurements there because the base circle does not come in contact with the shim. This is just how it should be. You've just got a little rust there.

Clearances not checked in 5 years.

Not smart!

Experience would count here, and I have none with this engine. For example, on some engines followers (buckets) are routinely changed, on others they'll outlive the engine.

I would try and get hold of a manual on the Lampredi SOHC motors that gives clearances and wear limits for the buckets and all and measure up. Looking is only a first step.

Then you can select the best components, re-cut the valves (utterly pointless not doing that) and re-shim.