We’ve had a couple of questions related to additives. I don’t know exactly how long after Ford put America on wheels the first products popped up laying claims to cure what ails your car, extend its life, improve performance, reduce fuel and oil consumption just to name a few but it couldn’t have been to long. Without looking too hard I found this ad from the SC Johnson company advertising its Car Savers, from the wax most know them by, to a carbon remover treatment.
Because there are so many different fluids and so many flavors of additives for those different fluids we’re going to break them down by system. Up first fuel additives.
Fuel additives are usually marketed in four basic flavors, fuel line anti-freeze/water remover, fuel system cleaners, fuel stabilizers, and octane boosters.
Heet is likely the best known anti-freeze/water remover. Does it work? Absolutely, all products sold as fuel line antifreeze, are all or almost all alcohol. The alcohol mixes with the water and allows it to mix with the gasoline. Is it needed or beneficial? It depends on a couple of factors. In much of the US what is sold as “gasoline” at the pump contains some alcohol, up to 10%. So if you use gas containing ethanol you’ve got more than enough alcohol in the tank already.
So what if you use un-adulterated gasoline? That depends some on the car. Until the 70’s direct venting of fuel tanks were the norm. So the normal expansion and contraction with temperature changes meant a lot of air was exchanged, increasing the opportunity for condensation to occur. Then the EPA brought evaporative emission controls into the picture. The early systems at a minimum forced the tank to breathe through a long hose greatly reducing the air exchange. With the advent of OBD-II systems it’s a closely controlled system all but eliminating air entering the tank. So it is likely unnecessary in modern cars, for most drivers, but for your Curbside Classic it may be indicated depending on climate and the fuel in your area.
Fuel system cleaners, these also go way back, though of course at the beginning they were sold as carburetor cleaners. Gumout is one that goes way back and is probably the best known. Do they work? Certainly many formulations do, though this is a crowded segment and undoubtedly the effectiveness will vary from brand to brand. The active ingredient is some type of solvent, naphtha is a common choice and many contain some type of oil along with an often small amount of their proprietary chemicals. Is it needed or beneficial? Fact is that since the mid 90’s there have been minimum fuel detergency standards in place in the US. That ethanol added to some gas is also a good solvent. So again for most drivers in most modern cars there really isn’t a need. But for your carb equipped Curbside Classic who’s fuel bowl is vented to the atmosphere an occasional or regular dose is likely a good idea.
Fuel stabilizers. This one that many Curbside Classic owners are likely to consider when they put it away for the sometimes long winter. Fact is fuel does go bad with age. It actually oxidizes and the different components can evaporate at different rates. With gas containing ethanol it can degrade in as little as 3 months. Looking at the MSDS for a number of them show that the common components are oils from “light” to “heavy”, naphtha, and a usually small amount of their particular proprietary component. The reasons given why they work range from that they are an anti-oxidant, to that they contain a more volatile compound that becomes that “target” of the oxidation process.
Hey wait a minute……..the components of the fuel system cleaners and fuel stabilizers seem pretty similar….hmmm.
Yup and you’ll find a number of products that claim to both be fuel system cleaners and fuel stabilizers, even if they are primarily marketed as for one or the other. The products that are primarily sold as stabilizers tend to have a thicker base than the cleaning products. In my research for this I noted that some people indicated that the products that use a heavy oil base sometimes seemed to leave their own residue. Others have noted good results using a product marketing as a combo cleaner/stabilizer for long term storage.
Octane Boosters. Many claim to make racing fuel out of ordinary pump gas. They seemed to take off with the intro of “low-lead” and reduced availability of extreme octane fuels in the 70’s. Do they work? Most brands have proven to raise the octane but it usually is an expensive way to get octane. If your car starts to ping after filling up at a questionable station it might provide what is needed to run that batch out. If you’ve got an old school super high compression engine and the race gas you normally use isn’t available then a couple or 3 bottles may be just the ticket. For the most part however fixing the underlying issue or changing your tune/set up to accommodate the fuel available would be more cost effective in the long run.
I mentioned gasoline containing ethanol a couple of times so we should probably discuss that since it certainly could be considered a fuel additive. I don’t want to start the debate of why it’s good/bad so hopefully we can stay away from the political side, there are lots of other sites to debate politics. Fact is some cities and states have mandated some or all fuel be E10, some metropolitan areas have year round or seasonal “oxygenated fuel” (E5.75%), other areas may contain anywhere up to E10 despite the lack of a State, Local, or Fed mandate.
Just to make it more confusing are the individual state’s labeling laws. It varies from prohibiting noting the presence of ethanol, others allowing it but not requiring it, to states that require at least a sticker containing words to the effect “may contain up to 10% ethanol”. So you may have to do a little research to see what exactly it is that you get from your local pumps. But knowing what you are putting in the tank of your car especially your Curbside Classic.
Now I’m not a chemist nor do I play one on TV, so if there are any chemists out there and can shed some more light on these products speak up. Have you had a particularly good or bad experience with fuel additives? Never used one in your life? Let us know.
They still sell Motor Cure under the Restore brand. I’ve used it but never “felt” it’s benefits.
If you do the math on most Octane boosters you’ll find that they don’t do as much as they appear to claim. They claim 7 points, that makes 93 octane 93.7 not 100.
The only one I’ve found that actually does work is Torco’s Accelerator. 16 ounces added to 10 gallons of 93 octane gets you 97. It’s twice or triple the price of most store bought boosters though.
I like the smell of race fuel so when I need high octane I usually just go to a station that has 99+ and blend it with whatever is in the tank.
Snake Oil is more about the perceived benefits than actual results. There are a lot of people that like being “sold” on stuff thinking they are doing a good thing for their ride.
Those were the guys who would give their cars a tankful of premium instead of regular gas as a special present, maybe after someone bought them a fancy imported beer.
My favorite was always Marvel Mystery Oil. I was never quite sure what it did. The cans said to add it to your gas and add it to your oil. I guess it was good for everything.
Where I grew up in Fort Wayne, Indiana, there was an old, old gas station called Barto’s Lubricated Gas – I think that they used to add some sort of additive to the fuel like Marvel’s.
Being the curious type in my earlier days, I used Marvel Mystery Oil in the gas tank of my ’77 K5 Blazer with a 350ci engine. It got rid of nearly all the valvetrain noises that were occurring.
As far as using additives on cars with an ECU, I wouldn’t bother.
Marvel Mystery Oil appears to be very closely related to Automatic Transmission Fluid and using ATF may produce similar results. I used to live near their HQ in Portchester NY but never went in.
Marvel Mystery oil cured the “quart of oil burned every 3,000 miles” in my 100,000 mile plus Oldsmobile 307 V8 in my 1987 Cutlass. However right around that time “MaxLife” oil came out and worked for me in the same way. Although it didn’t do anything for the ticking lifters the car had from the day my Dad bought it at 65,000 miles.
All the old fellows swear by it around here, as well as Sea Foam. And most of the time they know what they are talking about.
My favorite was always Marvel Mystery Oil. I was never quite sure what it did. The cans said to add it to your gas and add it to your oil. I guess it was good for everything.
Where I grew up in Fort Wayne, Indiana, there was an old, old gas station called Barto’s Lubricated Gas – I think that they used to add some sort of additive to the fuel like Marvel’s.
It was, if I remember correctly, a “top cylinder lubricant” – Mobil sold the same thing as Upperlube. It was for sticking valves, a problem that apparently happened a lot on older-design hardware.
The only use I had for Upperlube was in our Gravely Tractor…the six-horse Gravely-designed engine, the design which dated from the 1930s, had a flathead but cross-flow design; and the valve stems sat outside the air-cooled single-cylinder jug. The exhaust valve would stick WITHOUT FAIL on a long shutdown – long enough to completely cool; as in overnight or for a week.
Upperlube eliminated the problem, so long as you remembered to add it to the gas. I tried outboard motor oil; it didn’t work.
I suspect Barto’s Lubricated Gas just had a top-cylinder lubricant as an additive. Good if you had a Rambler or Jeep flathead…
Excellent analysis Eric.
In the 1990’s, I worked at Advance Auto parts and we sold a “miracle product” that caused no small amount of controversy. It was called Dura Lube and it was a love it/hate it product that mechanics generally didn’t recommend. It was mucho expensive.
One mechanic that I dealt with a bit explained that all of these “mechanic in a can” products that were made for the crankcase were basically oil thickeners that gave the illusion of power if the engine had worn rings or such. They also quieted noisy parts-for a while. He said that you could achieve the same thing with gear oil in the crankcase,but you better not plan on long term ownership if you did that. He was right. We sold a lot of these products (and 5 gallon buckets of gear oil) to small time used car dealers.
Most octane boosters make use of the fact that ethanol is a high-octane additive (e-85 is about 110-115 octane, depending on the blend). Everytime I’ve used an octane booster, I’ve noticed the same effect as fuel with a high ethanol content: poor mileage. As for fuel system cleaners, they do a fairly good job of keeping the fuel injector pintle clean, but products like Sea-Foam and Berryman’s seem to work better than Gumout or any store brand. I know pump gas has detergents in it, but they are not very concentrated. That’s where the injector cleaner additive comes in handy. I have seen an improvement of about 1-2 mpg in my 98 Suburban using Lucas Fuel System Cleaner. I know 1-2 mpg doesn’t sound like much, but when you started at 17 mpg on a 44 gal. tank, 18-19 is a marked improvement.
The most effective, and most toxic octane booster product used to be 104+ Real Lead, which as the name implied was basically a can of tetraethyl lead. Magazine testing showed it really would produce a boost if you started with premium unleaded gasoline but the stuff would dissolve plastic.
The other “interesting” products were carbon removers, most notably the John Muir solution for decoking a Beetle by slowly pouring a quart of diesel fuel down the carb while the engine was running and the old GM Goodwrench top engine cleaner which you would leave sitting overnight and which produced a massive smokescreen on startup as the crud went out the tailpipe.
Seafoam seems to work well when I put it in the gas tank. I also like slick 50 but I don’t know how well it works, if at all.
Sea Foam works good for it’s intended purpose, unlike many of the other ones.
I’ve used Sea Foam in my V50 from time to time, and a friend puts it in his boats regularly.
Good analysis Eric. I have had good luck with Seafoam and Marvel Mystery Oil. But you can do the same thing with a Coke bottle, some ATF, and water. ATF and kerosene are useful for many things. For diesel systems Lubro Moly Diesel Purge works wonders. But most over the counter cures don’t seem to do much.
Me and several friends know from personal experience that Marvel Mystery Oil works great for freeing up engines that are frozen up after sitting unstarted for decades.
Just squirt it into the cylinders, let it sit a couple days, and voila’. Liquid wrench does the same thing.
I’ve tried a fuel stabilizer for when the 2WD Ranger is mothballed for the winter (Stab-l), and it seemed to work OK, but have since switched to non-oxygenated fuel for the winter. Unless you have a 1954 or older, you can’t pump non-oxy directly into the tank, so I use cans. My small engines (generators, mower and such) all use non-oxy, so I’ve got a fair stash. FWIW, two-stroke mix seems to work better without ethanol in the picture.
Now, all I need is a replacement for Blitz’s !@#$% eco-safe filler spouts. Time to look for a quasi-portable tank and pump.
The ethanol in pump gas ate the rubber fuel line connectors and the soft carburetor parts in my ’66 Beetle. No one nearby sells non E10 gas either. I wish there was a way to get rid of the alcohol.
I am going to run a bottle of Techron thru my ’10 Hyundai’s tank next month to keep things cleaned up. I’ve owned it 2 years and haven’t put any additive in it yet but I hear it does keep your fuel injectors clean.
Look for a product called Star-Tron. It counter-acts pretty much all the problems inherent in ethanol use.
Good piece, Eric. I don’t use fuel additives but I can vouch for the “ethanol effect.” My car is new enough to be low compression with hardened valve seats, never had a trouble with regular gas until the past couple years. Cold starts would be hard and there was a sort of bog when I’d accelerate. When I heard that premium Shell has no ethanol I switched to that and noticed a difference as soon as I worked through the old stuff. I don’t know the chemistry behind it but computerless carbs just don’t like too much corn juice.
Octane booster: My brother’s Chrysler can only survive on 94 octane since he rebuilt the engine. The highest grade that most stations in our area sell is 91, so he always carries a container or two of octane booster for times when he needs gas and can only find a station with 91.
Stabilizer: When storing my cars, I used to just fill the tank with the same grade that I normally used and not use any additives. The car seemed a little low on power til that tank was run out in the spring, but otherwise everything was fine. Now that the gas has ethanol in it, I worry that it has a shorter shelf life and the ethanol may do bad things sitting in the fuel system. Now I fill my cars with hi-test (91 or 94 octane) and add Stabil before storing. Between these measures, the gas doesn’t seem to lose any zip after sitting for 6 months.
Fuel system treatments: In my area, newer vehicles require an emissions test every 2 years. The old-school mechanic that I take my wife’s vehicle to for E-tests recommends a shot of Lucas fuel system treatment in the full-up before taking the test. Normally that’s the only time I throw in anything but gas in the tank of that vehicle. However, last summer we took her 2006 CR-V on a camping trip in the Catskills. Something about the gas sold in that area (?) caused the CR-V to have starting problems the first time we started it every morning. I bought a bottle of Lucas fuel treatment and threw it in, and there were no more starting problems. It certainly seems to have some beneficial properties.
Your article only discussed gas engine fuel system additives. In my truck (1994 Cummins) I have started using Power Service diesel additive with every fill. It’s a cetane booster, but the main reason I use it is to improve the lubricity of the fuel. I’ve also read about some guys dumping some non-detergent motor oil in the gas tank on every fill-up. The new low-sulfur diesel does not lubricate as well as the older diesel fuel did, which will cause extra wear on injection pumps and injectors in older diesel engines. (Some jurisdictions are pushing for minimum levels of biodiesel blend as well, which will not help lubricity either.) The injection pump in my Cummins at least gets lubricated by crankcase oil, but many injection pumps in older diesels are ONLY lubricated by the fuel.
I assume part 2 of this series will be crankcase oil additives, so I won’t comment on those now.
Since I work at a Honda/Yamaha motorcycle dealership, I’m very familiar with carburetor cleaning on a piece of equipment that’s allowed to sit too long. Every gas can in the house gets Sta-Bil in it before filling, all my power equipment runs on stabilized gas, and if it looks like the motorcycles are going to sit the winter out they get it, too.
Anecdotal evidence and what with the horde of variables and the cost of performing truly useful “blind studies,” engine tear-downs, etc. modern fuel additives are assuredly of s YMMV nature.
Google “YMMV” if unsure of the acronym’s translation.
TechRon… found in Chevron and other branded gasoline.
Can be entered into vehicle if unavailable in your area’s petrol dispensing joints via black-colored plastic bottles.
Some human units gurgle the advice that a “dosage” be followed by an oil change soon thereafter.
Since it appears to cause no harm I give the Silverado with its 4.8 liter screaming creator of propulsive power a once-yearly TechRon treatment followed by an oil change.
Lots of online debate.
Bountiful in-depth discussion about all the lubes, etc. below
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=cfrm
My old Dodge Lancer turbo was very finicky about it’s fuel, it would only develop max boost if it had 91 or better octane. While I owned the car, I had tried every gasoline brand available to me, but the only one that ever seemed to deliver full boost was the old Amoco Ultra Platinum unleaded. No other fuel anywhere I bought it would ever give me full boost, including the other big names, like Mobil, Shell, Hess, Chevron, etc.
Occasionally, the car would develop a bit rougher idle than normal, usually after using cheap-o fuel when I would get stuck having to buy crap gasoline at some Interstate fuel stop. There were two grades of Techron, One was a fuel injector cleaner with Techron in it, which apparently was a lower concentration of the active ingredients, The actual Techron-branded fuel system cleaner which apparently had a much higher concentration of the active ingredients. The Techron branded fuel system cleaner worked as advertised, as it seemed to clean up the idle condition at least until I could find Amoco gasoline again.