i am looking at buying a '73 maverick with a 302. the guy im buying it from says that you have to put a lead additive in the gas or change the valves. he isnt very mechanical so i was wondering if there was any truth to this. if it is true would it be better/easier to change the valves or just buy some new heads
Lead gas is not a requirement for 73's it should be unleaded fuel only if it's still stock, the guy obviously doesn't know what he's talking about. I have a 71 and it runs on unleaded. I would advise a valve job though when you get it if nothing more then to be on the safe side cause the guy has no doubt used leaded gas.
I believe all Mavericks were built for leaded gas except maby Califirnia models. My 77 has nothing on it to suggest using unleaded. I had a 79 Bronco that was leaded gas vehicle. Anyway, lead helps lubricate the valve guides. The only time you might see any problems is if your up on the interstate every day running high speeds for prolong periods. For normal driving, you will probably never see any problems. If you decide to do a valve job, they will install hardened guides.
Unleaded Mavaholic - doesn't your 77 have the Gas Filler tube with the insert to prevent using the larger Leaded nozzle?? My 75 parts car had it - plus a sticker on the bumper saying Unleaded Fuel Only.
Leaded only.... The unleaded transition took place in 1975. (Maybe certain states required this sooner, I don't know). Light trucks continued exempt for several more years--that is why the Bronco had no catalytic converter, nor required unleaded gas. (I think as late as 1983 in Texas). The '73 was built for leaded gas. (Unless Ford was already installing hardened seats getting ready for the transition). One dead giveaway: If the Maverick has a bulge in the passenger floorboard, it came with a catalitic converter, whether someone has removed it or not. Also the filler tube came with the little flap door preventing the bigger leaded nozzle from getting into your tank.
It will run on unleaded gas. You can choose to add a "lead additive" if you wish. A lead additive is available at any auto parts store, Wal-Mart, etc. More than likely you can get by without adding the additive, as old cars have been running on unleaded now for over 10 years. When I had my 1970 Maverick, I used the lead additive for peace of mind more than anything.
Unleaded/leaded? My 74 250 6 has been running on unleaded since it was new. I think the switch over to unleaded may have happened here in Canada as early as California. However, I think my 96k miles car has some dieselizing now which indicates the valves may need work.
my 73 has no catalytic converter, nor the smaller gas fill tube. it came from texas originally. but It's been in california running on unleaded for 20 of it's 30 year existence...so, yes, it will run on unleaded..
The primary value of lead in the gas is valve lubrication, as stated above, but the guides aren't the real problem. The exhaust seats will wear much faster running a *leaded* car on unleaded. Fortunately, this is only an issue if you run prolonged periods of time at a higher rpm. The fix for this is to remove the heads and install hardened exhaust seats. This in the long run is cheaper than all the additives. If your car needs a valve job now, do this. If it doesn't, just run it on unleaded and wait until it needs a valve job or overhaul before bothering to do this. I don't believe Ford had heads with the hardened seats until the advent of converters in 1975. I remember they had some service bulletins in 1975 for valve wear problems. My mothers Granada got a valve job at 22,000 miles courtesy of Ford. Short answer, run the unleaded and don't worry about it.
Well said Max Power This was the big issue in all the car mags when leaded gas was being fazed out. If you was running the engine at a really high RPM for a really long time or got one of the really big muscle car engines or really hammer on that 302 every where you go, don't worry about it at all. If you want to Newbie you could buy some lead additive and add to the gas if you go on a long highway trip or want to really hammer on it sometime.
I have never used a lead additive on any of my older cars. While I am sure the valves will eventually beat themselves in the seats, that just gives me an excuse to pull the heads and work them over. You should be good for quite some time using unleaded gas.
Newby; I put new heads on my 302 a few months ago. Instead of rebuilding the ones I had, I got a set of rebuilts from an engine rebuilder, and they were very reasonable. I paid $230 for both heads, and that included rocker arms. I told them that I wanted hardened seats, and they said that is all they used, since you can't get unleaded gas anymore. So that may be an out for you when you need to fix the heads. Earl
well in light of this difference of opinion, i( i posted a similar question 6 months ago) i use a lead sub. gunk makes it. it adds 2 bucks to a tank. i may be dumping 2 bucks a tank down the toidy...my motor had 35 thousand original on it. i want to rebuild it when i am ready...not just cuz i didn't use sub, only to find out i shoulda. my .02
