How to Seafoam my engine
Every day auto forum members ask the same question: “Should I Seafoam my engine?” If you want to use Seafoam to clean fuel injectors, my answer is no. There are much better products to use in my opinion.
What is Seafoam engine treatment
Seafoam is one brand of engine treatment. The manufacturer lists three ways it can be used; poured into the crankcase to remove crankcase deposits, poured into the gas tank as a fuel injector cleaner, or sucked into a vacuum line as an upper engine or top engine cleaner. According to Seafoam engine treatement’s MSDS product safety sheet, it’s comprised of three liquids;
Pale Oil 40-60%
Isopropyl Alcohol 10-20%
So you’re looking at a product that contains a lubricating oil, a solvent, and alcohol. All three products can act to break up engine deposits. That’s what it claims to do. So far, so good.
Seafoam engine treatment as an engine cleaner
If you add Seafoam to your oil, it can dissolve buildup and deposits in your crankcase. Sounds good, right? Well, towards the end of this article I discuss the pros and cons of using an oil additive to do that.
Seafoam engine treatment added to your gas tank as a fuel injector cleaner
The two most effective fuel injector and fuel system cleaners are polyisbutylamine (PIBA) and polyetheramine (PEA). Seafoam doesn’t contain either of them. The Naphtha and alcohol components can act as solvents to clean deposits from fuel injectors, but I believe they’re not the best cleaners for fuel injectors or carbon deposits. I’m not sure how the Pale Oil helps clean fuel injectors, but keep in mind that Seafoam engine treatment claims that their product can be used in multiple ways, so as a fuel additive, perhaps the Pale Oil rides along for free and burns like ordinary fuel.
Seafoam engine treatment injected into a vacuum line to perform top end cleaning
When added to the gas tank, Seafoam engine treatment is applied to the back of the valves by the fuel injectors (in non-direct injection vehicles). But when used in a vacuum line, Seafoam engine treatment comes into direct contact with all the internal components located in the intake manifold. So the solvents have the potential to contact and clean valve stems as well as the back of each intake valve. Again, not the best cleaners, but they do clean.
Now let’s compare the chemical makeup of Seafoam and other products that claim to clean fuel injectors. I’ve picked some popular brands
The first two products on the list are multi-purpose cleaners Seafoam engine treatment and Gumout Multi-System Tune Up. You’ll see that they’re also oils, Naphtha, and alcohol
Sea Foam Motor Treatment SF-16, SF-128, SF-55 (Sold in bottles at retail stores)
Gumout Multi-System Tune-Up (Sold in bottles at retail stores)
Next we have products that are marketed specifically as fuel system cleaning products
Chevron Techron Fuel Injector Cleaner (Sold in bottles at retail stores)
Chevron Techron Concentrate Plus (SC) (Sold in bottles at retail stores)
Chevron TECHRON Bulk Gasoline Additive (added as a fuel injector cleaner at bulk storage sites)
Gumout All-In-One® Complete Fuel System Cleaner (Sold in bottles at retail stores)
Lucas Deep Clean™ Fuel System Cleaner (Sold in bottles at retail stores)
Royal Purple Max-Clean Fuel System Cleaner & Stabilizer (Sold in bottles at retail stores)
STA-BIL fuel stabilizer (Sold in bottles at retail stores)
ACDelco Upper Engine and Fuel Injector Cleaner (Sold in bottles at GM dealers and online)
As you can see, each product has a different chemical mix, ranging from distilled petroleum products to polyether amines (PEA) and glycol ethers and aryl alcohol. As you go from a general multipurpose cleaner like Seafoam and Gumout Multi System tune up, you’ll see the ingredients change from light oils and Naphtha to PEA, glycol ethers, trimethylbenzene and proprietary products. Keeping in mind that all Top Tier fuels require fuel injector cleaners, it’s worth reviewing the Chevron Techron bulk product that’s added at the fuel depot prior to deliver to the gas station.
Back to Should you seafoam your engine?
In my opinion Seafoam or similar products added to a tank of gas won’t hurt your engine, although I’m also not convinced that the light oils and Naphtha based products do much good. I think if you’re going to add a gas treatment to the tank, a product containing polyisbutylamine (PIBA) and polyetheramine (PEA) might perform better.
Next comes the issue of whether you should inject Seafoam or other top engine cleaners like the ACDelco Upper Engine and Fuel Injector Cleaner cleaner into a vacuum line. Here’s where I have a problem with the technique.
In a vehicle equipped with a MAF sensor, all incoming air is metered by the MAF usually mounted right after the air filter. As soon as you remove a vacuum line on a MAF equipped engine, you introduce UNMETERED air. The PCM sees the unmetered air by way of the pre-cat oxygen sensor suddenly going lean. The PCM responds by adding fuel. Now you inject Seafoam or Gumout Multi-Tune product into the intake vacuum line along with the added fuel. Whether you’re cleaning the valve stems and interior of the intake is almost irrelevant at this point because what you’re also doing is dumping extra fuel and cleaning solvents into the catalytic converter. What’s a catalytic converter? It’s an incinerator that’s designed to burn off excess fuel and oil. If the catalytic converter on your car is mounted in or right after the exhaust manifold, this injection technique can cause your catalytic converter to overheat and self destruct. Yup–a $1,000 repair bill because you tried to clean your engine.
So what can you do?
First, you can try another injection method. The ACDelco Upper Engine and Fuel Injector Cleaner product recommends injection by atomizing the product into the air intake duct, not a vacuum line. That way you’re not getting unmetered air past the MAF. To do this you can buy the product in an aerosol can or buy an atomizer canister. Load the liquid into it and pressure with compressed air. Then, spray the product into the air snorkel so it’s measured along with incoming air. As the product burns, the pre-cat oxygen sensor notices the richer mixture and the PCM cuts fuel trims. In my opinion, this is the only safe way to inject a top engine cleaner without destroying your catalytic converter. However, some car makers still warn against this method. They’re concerned that however much the PCM cuts back on fuel trim, this additional fuel may be too much for an exhaust mounted catalytic converter to handle.
For top engine cleaning, I prefer the ACDelco Upper Engine and Fuel Injector Cleaner atomized into the air duct prior to the MAF sensor.
Finally, there’s the issue of using engine flush solvents in the crankcase.
I have to honest, I’m not a fan of this at all. My opinion, of course, but if you take care of your engine with regular oil changes, you don’t need to add any solvents or flushing agents. I believe they do more harm than good. When poured into the crankcase as an additive, they tend to loosen deposits that can break away and clog oil galleries, hydraulic lifters, and the oil filter. So you think you’re doing your engine a favor and the next thing you know, you’ve got a lifter tick or engine knock. Instead, I would opt for more frequent oil changes if you’re at all concerned about deposits or sludge in your engine.
©, 2015 Rick Muscoplat
Posted on by Rick Muscoplat