leaded gas

[2637042]

my 73 imp with a 225 omc says that it required leaded gas. I have been using the lead supplement in it for years, but was wondering if it is necessary. i have heard that it dosent do anything, but have also heard that the lead lubercates the intake valve? any advice?

 

[navigator336]

Re: leaded gas

Engines designed to run on leaded fuel do not have hardened valve seats (unless you've had the heads re-done in the last decade of two and hardened seats were put in). The lead does not lubricate, but instead provides a cushion for the valve as it closes preventing it from damagine the "soft" seat. The lead substitutes do the same thing.

 

[MrBill]

Re: leaded gas

ratherb:<br /><br />Here's an interesting article from Chevron that specifically mentions marine engines. Take a look...<br /><br /> http://www.chevron.com/prodserv/fuels/bulletin/unld-gas/