question on lead free gas & oil.

[bobjob55]

I had been told,, way back ,, that older motors needed lead in the gas to run without ruining valves,,(stellite valves in newer engines ) ?? Also something about detergents in oil washing away too much stuff in motor ...anyone have any problems ???

[casper50]

I've read on here a few times that 40's and 50's mopars have hardened valves.  Gas shouldn't be a problem.  Don't know about the oil but from what I can see in my engine it could have used some detergent in the oil.  Huge amount of sludge deposits.

[Don Coatney]

I had been told,, way back ,, that older motors needed lead in the gas to run without ruining valves,,(stellite valves in newer engines ) ?? Also something about detergents in oil washing away too much stuff in motor ...anyone have any problems ???

Do a forum search. Both of these subjects have been cussed and discussed many times. Lead additive not required, detergent oil your choice.

[54Illinois]

I have heard the same about the gas...no lead needed.  Also, any oil is fine, been running 5W-30 Shell, National, Farm&Fleet SAE 30

[desoto1939]

I had been told,, way back ,, that older motors needed lead in the gas to run without ruining valves,,(stellite valves in newer engines ) ?? Also something about detergents in oil washing away too much stuff in motor ...anyone have any problems ???

One of the questions is does your current engine have any type of filter system installed on the engine? 

HAs you engine ever been rebuilt?

 

Mother MoPAr was way ahead of the game on engines back in the 30's.  They used harden values in their engines. The lead inthe gas was used as a lubrication agent.  So your current engine can run on unleaded with out any issue.  You do not need to use an additive to your gas.

 

A multi viscosity oil is a detergent oil which help to prevent sludge. So if your car used straight weight oil then I would stay with a straight weigth oil. If it had filter then you could use a multi viscocity oil. If you engine has been rebuilt recently then I would go to a  mulit oil.

 

But it is all up to you what you want to run in the egine.

 

Rich HArtung

[TodFitch]

. . . The lead in the gas was used as a lubrication agent.  . . .

No! Tetraethyl lead was used as a octane booster, not as a lubrication agent. In fact one issue with it was lead fouling ruining an engine, so they also added a lead scavenging agent. But the balance of the two was such that there was a little lead left, an amount they hoped wouldn't foul the engine too badly.

 

The valve cushioning effect was never the primary purpose but auto manufacturers took advantage of it with new engine designs starting in the 1950s to reduce costs: Why machine a recess and install hardened seats if you could skip the step?. And the valve seat recession issue was only really a problem in heavy duty applications (high power, high temperatures) like very high speed driving and towing trailers. During much of that era Amco sold unleaded gas and nobody worried about that ruining their engine. In the west you could get Richfield Boron which used a whole different octane booster and nobody worried about that ruining their engine.

 

All Plymouth (and I think all Chrysler product) L-6 engines from 1933 up had hardened exhaust valve seats and special alloy exhaust valves. So you don't need lead additive regardless of how you drive the car. And you probably don't need leaded gas in a '50s or '60s engine either as you probably aren't driving for hours on end at freeway speeds towing a trailer in the desert heat in your collector car.