Lead free head

[lellyden]

How can you tell the difference in a lead free head I've been sold one serpose to be lead free how can you tell. The valves have got 52 and 21 on them. Many thanks

[King Kenny]

The valve seats will be a different shade of grey than the rest of the head. When a head is converted the engineer will machine out the old valve seats and shrink fit new ones made from harder material thus preventing seat erosion.

[lellyden]

Would the valves still have 21 and 52 on them?

[King Kenny]

Quite possible. When I had my head done I got new valves but I could not tell you if they were standard or not. The problem with lead free fuel has been the erosion of the cast iron head seat rather than the valves.