Do add a lead additive to your unleaded gas?

Do you add a lead additive to your unleaded gas?

I just had to replace my valves seals . . . they were all dry out. broken up into pieces, and my car was burning blue smoke. I was told it was because the engine was designed to use leaded gas, and the previous owners never used a lead additive to keep the valve seals soft etc.

Do you add a lead additive to your unleaded gas?

 

Blue smoke generally means you're burning coolant if i'm not mistaken, check for a coolant leak. I dunno how thats related to the gasoline. As for lead additives if it don't say Unleaded Fuel Only on the gauge chances are you got a lead gas engine in that case yes add the additive to your next fill up. I don't know much about 69.5 Mavs mine is a 71 and uses Unleaded fuel. It might depend on your engine type too What kinda motor you got?


71 Grabber (Project Car)
85 Club Wagon
94 Taurus GL Sedan FFV

 

MavJoe,

I think you are right . . . the smoke may have been black not blue. Since the valve seals were replace no more smoke!!

I just wanted to get a feel for what others are doing with their leaded gasoline engines. I have a inline 6 and it has low miles on it so I figured I would get the seals replaced and run it while I work on the parts of the car first. I figure eventually I will replace it with a 302, but not until get the the exterior and interior redone first.

Thanks for your input!

 

when they went to unleaded fuel they went to hardend exhaust seats you can have hardend seats installed in your old heads and its a good idea to go to stainless steal valves i dont ever rember there being a difference on the seals as for the smoke blue usualy means oil white is coolant and black is rich fuel conditions


robert

 

lead substitute

yeah its a good idea to use it...
my dad and me have been using it now for a while

 

Just had the heads replaced on my '69.5. I had a blown head gasket, and I wanted to get rid of the '66 289 heads. I got a set of rebuilt '71 heads, with hardened seats. They were $116 each from a local rebuilder. Best thing I ever did for my Mav. Runs cool, no pinging, and smooth as silk. I am not sure if the '71 heads had hardened seats stock or not, but these were in the heads I bought. I think that you can get them in any head, if your request it.

Earl

 

it's normal for valve seals to wear out eventually. Especially the umbrella type seals that most manufacturers use now. I dont know of any way of keeping them from wearing and cracking, but regular oil changes really do help, as does keeping check on oil level. When the oil level drops, the engine tends to heat the oil more than normal, and this puts a bit more stress on the rubber-like seals. Same goes for dirty oil, it usually runs a few degrees hotter, and loses a lot of it's additives to keep rubber seals from deteriorating.

 

dunno

my dad puts a quart of tranny fluid and a few tablespoons of brake fluid in his crankcase before an oil change... He lets it run for about ten minutes then changes the oil... the tranny fluid helps to loosten up any build up , and the brake fluid softens up the seals ... Dont know if it helps or hurts ive never tried it but he's been doing it for years...

 

Thats basically the same thing as Gunk Motor Flush I used that stuff last oil change made a big difference.


71 Grabber (Project Car)
85 Club Wagon
94 Taurus GL Sedan FFV

 

to lead or not to lead

Valve seals don't wear out. they get old and break up, usually plugging up your oil drain back holes at the same time.
Lead Additive is for high comp, big cams, and lots of ignition, not "old" cars. It does nothing for exhaust valve seats. That's a bunch of BS and I got that from a machinist. It just makes money for them, just as the Y2K did for the puter programs out of work. Your Mav wouldn't know what to do with a Lead Additive.
I have a 82 Merc with a 460, 10-1 comp, 14 deg intial with 38 total advance using a 69 block, TRW pistons, DOVE heads and a 72 Mav 302, TRW pistons, 69 351W heads, 9.5-1 comp, and I use high octane in the Merc and regular octane in the Mav. And with no problems. Lead is to reduce knocking and pinging under load IE pulling a hill or racing.
As for trans fluid, all it is , is 10 weight, high deterent oil with a red dye in it. Brake fluid in the engine oil will ruin rubber seals before their time.
Head seats are cast iron just as the guides are, they're designed to wear out and be replaceable. The old "unleaded fuel required" was because of the restrictor in the gas filler tube. For those of us older to remember them. Depending on where you live you might be running 80/20 gas/corn squeezin, (still) in your gas, "gasahol" they call it. Or just plain old bad gas from the station. Try another station.
I used racing gas in my Merc when I drag raced it, 24 degs intial, with 38 total advance, but that was with a "big" cam and lots of load.

 

Well Now! I beg to differ! maybe someone NEEDS to go back to school!

 

The lead definitely helps for engines with non-hardened exhaust seats. But honestly I don't think it makes enough difference to worry about it; its a long term durability issue and I don't think any of these cars get driven enough to worry about it, plus you ARE going to swap some new heads on pretty soon right?

And the 'unleaded fuel required' was more for cat. converters than anything else.

 

real tech info

You know if you want some real Ford tech info try this website,
fordmuscle.com
There is some heavy duty mechanics on this site. You might be surprised what you read.

 

I'm always suprised by what I read on the internet, however it's rarely because it's the truth.

 

You the Bomb!