Hi everyone. My 66 ranchero has unharden valve seats so do i have to us a lead substitute. Is there somthing in gas today that does the same thing as the lead use to do? or can i put a small amount of oil in the gas? If i have to but a lead substitute in what works good? Thanks for any help
Your seats are way harder than you may think. There are thousands upon thousands of engines just like yours burning unleaded fuel with no issues.
Gunk has a lead substitute , i'm not sure if you really need it (there seams to be some debate about that) .... part # M5012 O'Reilly has it , i'm sure many others do too i use some in my `66 honda
I have to use lead additive in my non-HAMB mini because the heads are on the "soft" side on some Brit cars. But I think there are differences in each lead substitute, something to do with the chemical they use. Some have to be used with every tankfull. The one I use only has to be added every 1600kms (Canadian brand). I have no idea if Ford heads from that time are "soft" but I don't think you would have a problem.
We have been running unleaded gas in our hotrods for about 35 years now. Your 66 car was just a used car back then and most likely got more miles on it a year than it gets today. There was a huge panic back then that claimed all the old cars would need valve seats replaced. The sky is falling, the sky is falling. I imagine some have needed valve jobs and new seats over the years but they were doing valve jobs before they removed the lead. Shit breaks. Everyone has to make up their own mind but I've never seen any evidence of it becoming an epidemic caused by removing the lead. I bet that with truth serum some guys might admit that even with the additives they needed a valve job. I didn't buy a generator for the house in 1999 either. I'm such a daredevil.
Generally older engines like the 390 I am running in my F350 car hauler that pull a lot of weight will heat the exhaust seats and burn them out,,,,,,cars are a lot lighter and usually have no broblem unless you are pulling a trailer,,or a boat,,or something with a lot of weight,,,,car hauler weighs 7,200# plus load= hard exhaust seats....
.....I don't think you need it in your motor.....I run a couple of flatheads...try not to run no lead gas and do a lead substitute
I've never quite understood the function of lead in gasoline. My guess is that it was a sort of wetting agent to help transfer heat from the valves to the seats. That said I've driven the wheels off of pre unleaded cars, and pickups, and never had a problem with the valves. Around here they usually rusted into oblivion before the engines needed serious work. And not having to clean or replace spark plugs covered in deposits is an added bonus.
This was the purpose of lead. Remember, those of you who are antiques like me, the "best" gas back in the '50's was Amoco "white gas", NO LEAD. It cost a bit more but did not foul plugs and valves with lead deposits.
Every farmer out there is still useing a gas tractor. altho most work is done w/ diesel. no tractor was ever made w/ harden seats. after 1971 we pulled them all day long!! and many still do!
Just run it. Don't add anything silly to the gas. Tune it to use the modern fuels. If you don't have high pressure springs and a big cam you won't have anything to worry about.
Although the original intent of Lead in gasoline was as an anti knock agent, it had a side effect of stopping valve seat erosion. On cars that have non hardened valve seats, and are driven very hard for long periods of time, there will be visible wear in the valve seats. Anyone who has worked in a machine shop back in the 80's saw a fair amount of accelerated valve seat wear. Most of those engines were rebuilt with hardened seats that cure the problem. In today's world, most of us do not drive classic cars that still have original valve seats hard enough, or long enough to be a problem. It can still be a problem in work trucks that are loaded heavily and run hard, but the majority of us will never know the difference. Tractors typically don't run hot enough or at high enough RPM to cause much of a problem as well. You have to understand that this is a wear issue, so it's not like a catastrophic failure situation - it happens over time. As a side note, many 1960's and 70's Harley's (Shovelheads and Iron Head Sportster)do a have a problem with this as they run hot and hard - most have been updated by now.
And whatever you do, DO NOT try and put hardened seats in a Nailhead. You'll most likely ruin the heads. And they really don't need them regardless of what anyone says.
so this motor will likey last for a few years. im planing on stroking it when i get some money to do so.
From what I read on here it may be more to the point to worry about finding oil with enough zinc in it. Apparently one could have other more serious problems long before there is trouble with valve seats.
True, especially when you rebuild your engine, use an oil with a zinc additive or a good break-in oil if at anytime for the initial break-in, then try to use an additive afterwards unless you have a roller cam or cat.
I have a 1966 Impala and I have been asking myself the same question about the lead. I have used it and have not don't seem to notice a difference. Now if your seats were wearing out would you notice it and if so what are the signs?
I have never had a problem with non hardened seats and dont know anyone that has...I think it was a panic like someone else listed above....dont worry about it. For 99% of cars its not an issue...if you were running a blower or had this motor in a truck pulling a trailer or some other extreme operating conditions then maybe...otherwise..I wouldnt waste my money on seats or additives...
I ran a 1968 Chev 250 168,000 miles. Most of it on unleaded gas. Most of it on the Interstates. The motor was still purring. The smoking wiring harness was the reason I stopped running it.
I ran my 312 Y Block here in the UK without additive and it used to make a small but worrying knocking sound - so I started using a lead replacement additive and hey presto the sound vanished! Sticking with the lead replacement - $15 bottle lasts all year and I sleep better
As mentioned above, that is what it is for, an anti-knock agent, an octane enhancer. Anything it MIGHT do for the valves is a side benefit. You could probably get rid of the knock by backing off the timng a little.
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