I had my hot rod in for service at my local mechanic for a few odds and ends. While there, it ran out of gasoline. Thinking that he would be helpful, he went to the nearby airport and picked up 5 gallons of leaded aviation fuel. He needed the engine to run for some of the servicing. Anyway, he may have used a gallon or so of AvFuel. When I told him that the car had a catalyst he dropped and drained the tank and put in 5 gallons of ethanol free Sunoco Recreational fuel. So my question is: How much leaded fuel will ruin a catalyst? I had a new custom welded exhaust put on the car a few years ago. I doubt that I have 3-4,000 miles on it. So the cat is virtually new. Any thoughts or advice would be appreciated. Thanks
How much Lead will ruin a catalyst?
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You've got to be kidding, this is almost too much to believe. That is one worthless mechanic.
For the most part any damage done will reverse within time. 100LL is low lead compared to the automotive fuels of the past anyway.
For the most part any damage done will reverse within time. 100LL is low lead compared to the automotive fuels of the past anyway.
The answer? Who knows. Spark plug life is also affected, but a gallon will do very little harm. But you also have O2 sensors to worry about.
Originally Posted By: Building3
I am old enough to remember cars without catalysts and they did not smell with the gasoline of the day. Now, when I run my older non-catalyst cars (vintages 1966 to 1972) they smell from the gasoline. There are no exhaust leaks and the carburetors don't leak. Even tweaking the mixture to run a bit lean is no help. So can anyone tell me why the smell is only on cars without catalysts? Did the government make the refiners add something to the gasoline so that non-catalyst cars would smell? I used to use "normal" 93 octane fuel that I use in my daily drivers, then I switched over to ethanol-free gasoline hoping that the smell would go away. It did not. Is there any additive available that would diminish the odor? Thanks
What kind of hot rod do you have now that has a catalyst in it?
I am old enough to remember cars without catalysts and they did not smell with the gasoline of the day. Now, when I run my older non-catalyst cars (vintages 1966 to 1972) they smell from the gasoline. There are no exhaust leaks and the carburetors don't leak. Even tweaking the mixture to run a bit lean is no help. So can anyone tell me why the smell is only on cars without catalysts? Did the government make the refiners add something to the gasoline so that non-catalyst cars would smell? I used to use "normal" 93 octane fuel that I use in my daily drivers, then I switched over to ethanol-free gasoline hoping that the smell would go away. It did not. Is there any additive available that would diminish the odor? Thanks
What kind of hot rod do you have now that has a catalyst in it?
Back in the early 80's we had a lot of servicemen with papers allowing cat removal for Europe. Germany at that time had vary little no lead gas.
The cats that were not removed lasted a few months before plugging and the O2 which could not be be removed in every case I saw lasted about a year, parts stores at that time had a huge stock of O2's for US cars. Going by that I would say you don't have a problem.
The cats that were not removed lasted a few months before plugging and the O2 which could not be be removed in every case I saw lasted about a year, parts stores at that time had a huge stock of O2's for US cars. Going by that I would say you don't have a problem.
Today's 100LL generally contains less than 2g Pb per gallon. 100LL can contain UP TO 2.0 g/gal. However, much of today's 100LL is actually 100VLL (very low lead) and has considerably less.
Note: in 2011, the FAA approved the use of 100 very low lead as an equivalent replacement for 100LL. I've heard that the 100VLL is now commonly in use, it's still called 100LL though.
There is some question as to how much lead is really in 100VLL. Some sources say it's as low as 0.5g/gal.
https://www.nbaa.org/ops/environment/avgas/20110914-FAA-SAIB-NE-11-55.pdf
Note: in 2011, the FAA approved the use of 100 very low lead as an equivalent replacement for 100LL. I've heard that the 100VLL is now commonly in use, it's still called 100LL though.
There is some question as to how much lead is really in 100VLL. Some sources say it's as low as 0.5g/gal.
https://www.nbaa.org/ops/environment/avgas/20110914-FAA-SAIB-NE-11-55.pdf
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So removing the lead means sooner servicing of engines? What is replacing the Lead in the Av fuel?
Originally Posted By: Vern_in_IL
So removing the lead means sooner servicing of engines? What is replacing the Lead in the Av fuel?
MMO
So removing the lead means sooner servicing of engines? What is replacing the Lead in the Av fuel?
MMO
you should not experience any issues with the small amount of fuel that was burned. you probably consumed around 2 grams of lead.
it's a misconception that the "low" part of 100LL is really low; up to 2.2 grams per gallon are allowed (very similar to auto gas from decades past) the "low" in 100LL refers to the fact that its lower than the 4.2 grams/gallon that was/is typical of 100/130 green Av Gas.
I could tell from smell and dirty oil from my brother's plane that the oil was really dirty and nasty; I attributed it to the lead in the fuel; but that is only a guess. and that was with maybe 50 hours on the oil; and 3 quarts top up between oil changes.
but I'm pretty sure you are fine. yes, there are some regulars at the airport who purchase 100LL; I'm not sure if they understand what they are doing. also, my 1970 Cougar was run for years on unleaded gas; no valve problems.
it's a misconception that the "low" part of 100LL is really low; up to 2.2 grams per gallon are allowed (very similar to auto gas from decades past) the "low" in 100LL refers to the fact that its lower than the 4.2 grams/gallon that was/is typical of 100/130 green Av Gas.
I could tell from smell and dirty oil from my brother's plane that the oil was really dirty and nasty; I attributed it to the lead in the fuel; but that is only a guess. and that was with maybe 50 hours on the oil; and 3 quarts top up between oil changes.
but I'm pretty sure you are fine. yes, there are some regulars at the airport who purchase 100LL; I'm not sure if they understand what they are doing. also, my 1970 Cougar was run for years on unleaded gas; no valve problems.
as a side note, Mobil paid for the repairs on alot of Aviation engines. plenty of engine failures with lead sludge when they sold their Mobil 1 avaiation oil. from the engineering reports, it seems that part of the problem was the fact that many personal planes sit alot, and the lead would not stay in suspension. IIRC, the higher use planes (flight schools, other commercial planes) had little to no problems. AMSOIL, Mobil, others, do not recommend synthetic oil for aviation piston engines that use leaded fuel.
That earlier post was for a Mustang and a Road Runner, not this car that had the lead put into it. It is a Prowler. I put a new custom exhaust on it and the cat looks more like a resonator, so the mechanic thought he was doing me a favor by using this high octane AvFuel.
Thanks for the responses. it looks like I won't have a problem.
Thanks for the responses. it looks like I won't have a problem.
Your mechanic thought that AvGas was appropriate for a street driven vehicle? And upon finding out it wasn't drained said AvGas and put in a fuel intended for a UTV, motorcycle or boat?
He would never touch anything of mine.
What fuel do you use in your Prowler?
BUT, if your story is 100% true, you have no worries. It would take a lot more than a gallon of low lead to coat the catalyst and render it ineffective. Your bigger problem is what else the "mechanic" may have done to be helpful.
He would never touch anything of mine.
What fuel do you use in your Prowler?
BUT, if your story is 100% true, you have no worries. It would take a lot more than a gallon of low lead to coat the catalyst and render it ineffective. Your bigger problem is what else the "mechanic" may have done to be helpful.
Originally Posted By: Building3
I had my hot rod in for service at my local mechanic for a few odds and ends. While there, it ran out of gasoline. Thinking that he would be helpful, he went to the nearby airport and picked up 5 gallons of leaded aviation fuel. He needed the engine to run for some of the servicing. Anyway, he may have used a gallon or so of AvFuel. When I told him that the car had a catalyst he dropped and drained the tank and put in 5 gallons of ethanol free Sunoco Recreational fuel. So my question is: How much leaded fuel will ruin a catalyst? I had a new custom welded exhaust put on the car a few years ago. I doubt that I have 3-4,000 miles on it. So the cat is virtually new. Any thoughts or advice would be appreciated. Thanks
You'll be fine it was minimal run-time.
I had my hot rod in for service at my local mechanic for a few odds and ends. While there, it ran out of gasoline. Thinking that he would be helpful, he went to the nearby airport and picked up 5 gallons of leaded aviation fuel. He needed the engine to run for some of the servicing. Anyway, he may have used a gallon or so of AvFuel. When I told him that the car had a catalyst he dropped and drained the tank and put in 5 gallons of ethanol free Sunoco Recreational fuel. So my question is: How much leaded fuel will ruin a catalyst? I had a new custom welded exhaust put on the car a few years ago. I doubt that I have 3-4,000 miles on it. So the cat is virtually new. Any thoughts or advice would be appreciated. Thanks
You'll be fine it was minimal run-time.
Originally Posted By: maxdustington
Originally Posted By: Vern_in_IL
So removing the lead means sooner servicing of engines? What is replacing the Lead in the Av fuel?
MMO
Hahahahaha, made me laugh!
But interestingly enough, it may be MMT. So you are only off by a letter.
MMT(Methylcyclopentadienyl manganese tricarbonyl) is used in refineries worldwide to raise the octane of fuel as an alternative to TEL (Tetra-ethyl lead) but is far more environmentally friendly than lead and is not harmful to emission control devices. This is the favoured active compound in most good quality octane boosters. It typically leaves a flat reddish color on the plugs and in the tailpipe.
Originally Posted By: Vern_in_IL
So removing the lead means sooner servicing of engines? What is replacing the Lead in the Av fuel?
MMO
Hahahahaha, made me laugh!
But interestingly enough, it may be MMT. So you are only off by a letter.
MMT(Methylcyclopentadienyl manganese tricarbonyl) is used in refineries worldwide to raise the octane of fuel as an alternative to TEL (Tetra-ethyl lead) but is far more environmentally friendly than lead and is not harmful to emission control devices. This is the favoured active compound in most good quality octane boosters. It typically leaves a flat reddish color on the plugs and in the tailpipe.
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