Yep all understood. I think that realistically looking at the VW head design
compared to a Lycoming for example the total cooling surface area is a lot
smaller on the VW. So heat removal is a bit more critical
But no real drama. It just means good maintenance ... watching tappets
clearances
I replaced both heads recently (575 hrs) and found significant intake valve
"pocketing" on all four intake valves and seats. In other words, the valve
face and seat face were no longer flat but rounded, but still mated well
enough to give good compression. The wear had gotten to the point where
Do you have photos of the distortion/damage to the valves and seats?
regards
Rob
Rob Thompson
0429 493 828
On Tue, Dec 1, 2020 at 6:55 PM Ian Williams wrote:
> Hi All,
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>
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> I thought an interesting situation I have had with these little engines.
>
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> I “look after” ie the maintenance
Hi Rob.Sorry didn’t. Engine is back together again. What I saw was that
as I was lapping in the valves there was a darker area on the inlet valve seat
where it passes by the exhaust seat which I couldn’t get rid of by lapping.
Ian W
Sent from my iPhone
> On 2/12/2020, at 9:56 AM, Rob
The exhaust side of the inlet valve seat cops a lot more heat so can be
prone to distortion and heat hardening.
Nigel was investigating ceramic coatings inside the heads and ports to get
the exhaust heat out the pipe not into the metal.
Approvals to use ceramic coatings may be a problem. Possibly
