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| | | | Joined: Oct 2005 Posts: 738 Shop Shark | | Shop Shark Joined: Oct 2005 Posts: 738 | So, I am pretty sure that when my 1961 Chevy was born it would have been run on leaded gasoline. When the switch to un-leaded was made did they have to re-tune cars, or replace any parts? Will my engine last longer if I put in some of that lead additive every fill up. I do not do that right now, but should I??
Anyways, I was just curious. I see no negative side effects right now. My old 235 chugs away happily on regular unleaded like an old man on metamucil...so I see no need to change anything.
Kyle
"Never tell people how to do things. Tell them what to do and they will surprise you with their ingenuity." - George S. Patton My Machine | | | | | Joined: Feb 2000 Posts: 5,223 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,223 | Lead was a lubricant and heat transfer agent. Its not needed anymore due to the harder valves and seats. I have heard the old valve seats have enough lead pounded into them you don't need to add it any more. If you are working the old truck hard pulling heavy loads, don't worry about it. Joe | | | | | Joined: Jul 2005 Posts: 1,158 Shop Shark | | Shop Shark Joined: Jul 2005 Posts: 1,158 | I wouldn't worry about it.
If you want to make sure, you can do one of two things:
a) replace the valve seats
b) put a lead additive in your tank.
But, as I said, I wouldn't worry about it. As Joe H said, The valve seats probably have enough lead pounded into them that it won't be an issue. | | | | | Joined: Dec 2002 Posts: 3,442 Moderator - The Electrical Bay | | Moderator - The Electrical Bay Joined: Dec 2002 Posts: 3,442 | I use a lead additive/replacement chemical... I just pour in a few oz's when I gas up..
Another quality post.
Real Trucks Rattle
HELP! The Paranoids are after me!
| | | | | Joined: Nov 2002 Posts: 2,766 Carburetion specialist | | Carburetion specialist Joined: Nov 2002 Posts: 2,766 | The lead was used as an octane booster. There was a side benefit of valve lubrication. Assuming the gasoline you are currently using has the same octane (and the same caloric content) then no calibration changes will be necessary.
As to the lead additives:
I don't personally use them (nor will I). If the engine ever requires rebuilding, I have the machinest install hardened valve seats, which totally eliminates the problem of valve seat recession in any except the most over-stressed engines (possibly a tractor plowing in gumbo soil, or a pickup pulling a 40 foot travel trailer???. Others may have differing opinions.
Jon.
Good carburetion is fuelish hot airThe most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes!The Carburetor Shop | | | | | Joined: Apr 2006 Posts: 236 'Bolter | | 'Bolter Joined: Apr 2006 Posts: 236 | As others have stated, the lead acts as a lubricant for the valves. Personally, I've been driving my 58 for many years with unleaded gasoline, and the engines still runs strong. I figure that I'll have hardened valve seats installed when and if the engine needs rebuilding. Until then I see no reason to go to the expense of installing new valve seats until the old ones wear out.
58 Fleetside, 235, "The Old Buckin' Bronco"
| | | | | Joined: Jun 2004 Posts: 103 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2004 Posts: 103 | Marvel Mystery Oil is a good top lubricant! Put a few ounces in the gas tank when re-fueling. First Do No Harm! :-) BW | | |
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