leaded fuel ???

[Arlie]

I have a 1973 murcruiser 302 ford. My question is, there is a warning label on the engine and in the service manual that says to use leaded fuel 93 octane this may sound stupid but does that mean I have to get lead additive? Ser # 3601224 Thanks

 

[John3]

Re: leaded fuel ???

If the valves & seats are original I would use the additive. If there was a valve job & they were changed then you should be ok with unleaded.

 

[HT32BSX115]

Re: leaded fuel ???

I have a 1973 murcruiser 302 ford. My question is, there is a warning label on the engine and in the service manual that says to use leaded fuel 93 octane this may sound stupid but does that mean I have to get lead additive? Ser # 3601224 Thanks

No.............You cannot buy real "Lead Additive"...... no one makes it and it's illegal to use in cars AND boats........ There's lead "substitute" available but most of us call it "Snake-Oil"

The valve seat thing is a myth. I know many people who have in the past ran their (unmodified) cars and trucks (hundreds of) thousands of miles on unleaded gasoline AND propane. I don't think there's a snake-oil you can use with propane to "save" the valve seats.

Just run regular pump gasoline of the correct AKI and ensure the engine is timed correctly.......

My previous boat (1966 Mark Twain, 6cyl 230 CU-in) went 39 years before I sold it and never had the head off.......

It got "unleaded" pretty much all it's life before I sold it in '05.


Regards,


Rick




If it REALLY bothers you, you could run a mix of regular gasoline and AVGAS (which still has tetra-ethyl lead in it) but you'd be putting lead compounds into the water and wasting a lot of money too.....

 

[John3]

Re: leaded fuel ???

........The valve seat thing is a myth........

I have only one word to say about that!
Ferrari

 

[HT32BSX115]

Re: leaded fuel ???

I have only one word to say about that!
Ferrari

The OP has a Ferrari in his boat?

 

[AviatorJim]

Re: leaded fuel ???

I agree with Rick. 1 part AVGAS to 4 parts unleaded gets you real close to what the old leaded fuel was. But I'd just run unleaded. not with the money and hassle.
-Jim

 

[HT32BSX115]

Re: leaded fuel ???

I agree with Rick. 1 part AVGAS to 4 parts unleaded gets you real close to what the old leaded fuel was. But I'd just run unleaded. not with the money and hassle.
-Jim

Last week I filled my Four Winns Liberator at Lake Shasta............ 23 gallons @ approx $137!

Just filled up the Stinson today............ 22 gallons @ approx $135

 

[John3]

Re: leaded fuel ???

Last week I filled my Four Winns Liberator at Lake Shasta............ 23 gallons @ approx $137!

Just filled up the Stinson today............ 22 gallons @ approx $135

And your Grand Children will tell their Grand Children about these good old days of cheap Gas

 

[Outsider]

Re: leaded fuel ???

More likely his granchildren will have to explain to their grandchildren what gas was ... :facepalm:

 

[HT32BSX115]

Re: leaded fuel ???

And your Grand Children will tell their Grand Children about these good old days of cheap Gas

Yeah! I remember my dad complaining about the price of gas on Lake Powell at the Rainbow Bridge Marina in 1966. $0.49/gallon.

He thought that was WAY too much!!

 

[matt167]

Re: leaded fuel ???

Well, valve seat depression does happen over time, but it takes a long time under normal use. Even old Gas tractors still run strong after 40-60+ years of hard service with few valve issues ( unless someone forgot the rain cap ). Nothing to really worry about.... But Tetraethyl lead additive is available. Just extremely expensive. Octane Supreme


Also, I would have to look it back up, but I remember reading that Ford used hardened seats as early as 1972, so it may be good right from the factory and Merc added it to cover various engine builds.

 

[Oshkosh1]

Re: leaded fuel ???

Well, valve seat depression does happen over time, but it takes a long time under normal use.

Example of said "depression"...a 40y/o head off of my GM250 CID inline 6. Note the "depressed"/flush valve faces.

 

[HT32BSX115]

Re: leaded fuel ???

Well, valve seat depression does happen over time, but it takes a long time under normal use. Even old Gas tractors still run strong after 40-60+ years of hard service with few valve issues ( unless someone forgot the rain cap ). Nothing to really worry about.... But Tetraethyl lead additive is available. Just extremely expensive. Octane Supreme


Also, I would have to look it back up, but I remember reading that Ford used hardened seats as early as 1972, so it may be good right from the factory and Merc added it to cover various engine builds.

Yeah. I went to that site. That stuff is REALLY expensive. I would still question if it actually does have TEL in it or is it just another Snake oil!

If you MUST have leaded fuel, just get some AVGAS. and blend it like Oshkosh suggested...... It's available at just about EVERY small airport around the country! Even with 100LL (100 octane "low-lead") the levels of TEL are higher than was ever used in automotive petrol..... But I still don't think it's necessary in any low compression marine engine.

I would also say that if you took 2 engines side by side and ran them 40-60 years with one running leaded and the other unleaded fuels, BOTH would be seriously worn out! Most marine engine's die from poor or lack of maintenance. They almost never "wear" out!

 

[Arlie]

Re: leaded fuel ???

Great, will just go with unleaded and not worry about it. Thanks for explaining and not just telling me yes or no. I think I remember riding in a car when I was a kid that took lead additive but that was the one and only time I've heard of it being used. Thanks. Use to fill up my moped for less than a dollar was pissed off when I got my first car and gas was just over a dollar. LOL wish I could get it for that price. So not going to use $$$$ additive. Would rather redo valves, but that doesn't sound like much fun (if it ant broke don't fix it). 1994 0.75/gal. Thanks

 

[Georgesalmon]

Re: leaded fuel ???

When I was in college I worked at a Clark station at night. Gas was $0.329 AND we gave Green Stamps, lol.