I have been fixing up a 98 6N Polo 1L that I got recently, which has the AER engine. The car has 34000 miles on the clock, which appears genuine judging by the general appearance of the car. I.e. the interior seems hardly worn. It is not on the road yet so I can not take it out for a spin.

However I noticed the idle was a bit odd and I found that number two pot was not firing at low revs of 680rpm, although it came in at slightly higher revs of 1000rpm.The engine was very quiet when warmed up no hint of worn tappets. I did a compression test and number two was down so off came the head.

I found that the tappets and camshaft were in a very poor state. See the images below. I still think the mileage is genuine as I can still see the honing marks on the bores and the cylinder head is very clean with no blackened oil deposits inside the cam cover. The valves and seats are Ok with just a bit of blackening on number two exhaust valve seat but no excessive pitting. What has happened then, a previous owner doing very short trips?

I have another engine in the garage so I will probably just swap cylinder heads and then check the oil pump pick up and oil pressure.

Oil starvation usually affects the bottom end quite hard,particularly the big ends,so if this is fine then I'm thinking that my first line of enquiry would be oil starvation to the head. But how i dont know,it cant be possible to put the gasket on the wrong way around surely? Maybe something stuck in the oilway?

If it was water in the oil,the pump would've picked up pure water on start up because its heavier than oil and sinks to the bottom. This would've killed the bottom end too.

If the head is good,you only need cam and tappets. But is it? Could there be a casting fault,or other manufacturer fault with that mileage? Id have to see the engine,its a strange case.

i'm no expert but it looks a bit like corrosion to me, i take it that it has been stood awhile so maybe condensation has formed underneath the rocker cover and dripped on to the cam then onto the tappets

^^ yeah that looks like plain old corrosion to me, probably been sat up for years without being run. frost got in and killed it

I think the car had been stood awhile. It does not look as if the head has been off before, the head gasket seemed Ok.

The tappets have quite an indentation, if I put a straight edge across the face I can get the edge of a 0.2mm feeler gauge underneath at the centre. The lobes of the cam are not square either.

It's got to be corrosion, as you can see it on areas of the cam that don't contact the tappet, but it must have been run a fair while after standing to do all of that damage.

Not being a lover of flushing oil, I would put clean oil in it after the repair and then change it (and the filter) again after you have run it for a day or two.

Regards.