Dave,
Original research gave the indication that a shift from leaded to
unleaded fuels was going to be a big problem. this was because the tests
made were in the lab with engines run under severe conditions. As in
many other engineering theories, the real world has shown us a different
picture.
The conventional wisdom is that unless engines are run under consistent
high load/high rpm conditions (stationary engines, hard working trucks,
farm tractors, etc.) there isn't likely to be a noticeable change in the
engine's valve life with the unleaded fuel.
The rest of the story is that lead from the leaded fuels not only lubed
the valves which helped their life expectancy, it also created other
problems. Which included lead buildup on the valves and valve seats, the
reason for valve spring rotators, 45 degree seats and higher spring
pressures, also shorter spark plug life and other wear problems within
the engine. So likely the engine will have an improved life on unleaded
fuel.
Tom, Redding CA - #216 D/GCC
Dave Seely wrote:
> I have just helped a friend get his 1935 International Truck on the road and
> he asked a really good question. Can he run unleaded gas in the stock blue
> diamond flathead six? I thought he could because in the old days premium
> gas was called ethyl because they added tetra-ethyl-lead, therefore the
> lower octanes (like you would run in a farm truck) would be low or no lead
> gas. I know they now add hardened valve seats, but this is just an old
> flathead with a loose old valve train and probably limp springs and low
> compression because of the design itself. There is probably enough lead
> deposited on the valve face to last a long time. What do y'all think?
/// unsubscribe/change address requests to majordomo@autox.team.net or try
/// http://www.team.net/mailman/listinfo
/// Archives at http://www.team.net/archive/land-speed
|