Inliners International Forums General Discussion Engines Hardened Valve Seat Inserts and unleaded fuel . . .

Air pollution systems aren't relevant on cars from the seventies... and I suspect this thread is about cars from the sixties, right?

And I wasn't talking diesel at all. Petrol injected Peugeot 504.

The fungus was affecting what we lovingly knew here as 'Lead Replacement Petrol'... I think it had a lot of potassium or something to supposedly help with VSR... whatever it had it didn't work. Anyway, the fungus was something that you didn't strike often, but it was a known problem.