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What is cylinder glazing, and can you fix it without tearing down the engine?
In the large majority of cases, yes. Cylinder glazing can look like a symptom of serious mechanical wear, but in most cases the engine isn't worn out at all. Most often, the cylinder wall is actually imbedded with hard carbon deposits that have been polished mirror-smooth by the reciprocal motion of the piston and piston rings. That carbon build up is destroying the compression ring seal. The good news is that the carbon build-up can be an easily fixable problem.
When many engines are rebuilt to overcome problems such as excessive oil use, low compression, and blow-by, it is very often found that they are not excessively worn, but are only heavily carboned-up, particularly on the cylinder walls and in the compression ring grooves. These are exactly the types of engines that can be effectively recovered without a costly rebuild.
FTC Decarbonizer fixes cylinder glaze at its source. It is a unique fuel catalyst that works during normal engine operation, catalytically enhancing the combustion process and oxidizing the hard carbon from the cylinder wall cross-hatch micro-grooves and the compression ring grooves simultaneously. No teardown required.
What is cylinder glazing?
Cylinder walls have cross-hatch micro-grooves machined into their surfaces. These micro-grooves hold the essential engine oil needed for the compression rings to seal correctly against the cylinder wall. Without that critical oil film, the rings won't seal properly and the engine will lose compression.
Cylinder glaze is what happens when hard carbon fills those micro-grooves and becomes polished smooth. The carbon builds up over time as a result of incomplete or inefficient combustion. As the piston moves up and down, the compression rings rub against the carbon-filled surface and polish it progressively smoother. Eventually the surface becomes glass-like -- shiny, mirror-smooth, and unable to retain adequate oil film.
A viable cylinder wall has a visible cross-hatch pattern — fine grooves machined at opposing angles into the surface, dull and slightly rough to the touch. A glazed wall looks the opposite: smooth and reflective, almost mirror-like, with no visible texture. Often, this is not a sign that the cylinder is worn smooth. Frequently, it is a sign that the micro-grooves are just packed with polished carbon. The underlying wall may still be dimensionally correct, but the surface grooves can no longer perform their vital function.
Signs your cylinder walls are glazed
Cylinder glazing affects both gasoline and diesel engines. It doesn't usually announce itself with a single obvious symptom. It shows up as several things progressively getting worse over time.
The symptoms of cylinder glaze overlap significantly with those of stuck compression rings. Both conditions share the same cause and usually occur together. The difference is in action: stuck compression rings considerably diminish the ring-seal effect by stopping both the ring's natural outward expansion against the cylinder wall, as well as blocking compression pressure getting behind the ring to further intensify the sealing effect. Meanwhile, cylinder glaze degrades ring-to-cylinder sealing by reducing the cylinder-wall oil film needed for compression-ring sealing.
In practice the symptoms are similar, but pure cylinder glaze without stuck rings tends to produce a more gradual onset of problems. By the time symptoms are obvious, both conditions are usually present.
Excessive oil consumption.
The oil film in the cross-hatch micro-grooves is vital for correct compression ring seal against the cylinder wall. When the micro-grooves are glazed over with compacted, polished carbon deposits, the all-important oil film cannot be maintained. Consequently, too much oil gets past the rings into the combustion chamber and is burned. The engine uses more oil than it should, and blue or grey exhaust smoke is often seen. On gasoline engines, oil-fouled spark plug tips are often a reliable field indicator. Stab-revving a stationary gasoline engine and watching the exhaust for blue smoke is another quick check.
Low or uneven compression.
A compression test is often a reliable way to confirm ring seal failure from cylinder glaze. Low readings across cylinders, or readings that vary significantly between cylinders, can be a highly likely indicator. Further confirming tests are recommended. When the cross-hatch micro-grooves are packed and polished smooth with carbon deposits, the oil film is no longer assisting the compression seal. Consequently, the compression rings lose part of their sealing effect regardless of whether the rings themselves are stuck or in otherwise good mechanical condition.
Blow-by.
Combustion and compression pressure that escapes past the compression rings into the crankcase is a direct sign of ring-to-cylinder seal failure. Check the PCV valve pipe for oil vapor or residue and watch for pulsing pressure or vapor when the oil filler cap is removed. On many diesel engines, look for smoky vapor or oil droplets from the engine breather tube. Pressure pushing oil mist out of any of those vents is blow-by.
The engine feels flat.
Pressure escaping past the rings is pressure that isn't pushing against the piston. Engine power is lost. Fuel economy drops. The engine feels sluggish overall and just doesn't operate the way it used to.
Cold start problems, particularly on diesel engines.
Diesel engines ignite and combust fuel through compression pressure alone. When cylinder glaze has degraded the ring seal and, consequently, reduced compression pressure, a cold diesel engine may crank longer before finally starting. Additionally, thick white exhaust smoke - partially combusted fuel vapor – is often visible on startup, and clears only once the engine reaches operating temperature. Gasoline engines are less affected at cold start because they don't rely on compression for ignition. Spark plugs ignite the fuel in gasoline engines. However, severely low compression can cause hard start conditions.
What causes cylinder glazing?
Cylinder glaze is caused by hard carbon deposits that accumulate in the cylinder wall cross-hatch micro-grooves and are polished smooth by the reciprocal movement of the compression rings. The carbon is a byproduct of incomplete or inefficient combustion.
Incomplete or inefficient combustion — from extended idling, short-trip driving, light engine load, poor fuel quality, or an engine running rich — creates unburned carbon residue. Most of that carbon is expelled through the exhaust. But a significant portion accumulates on the pistons, the ring lands, the compression ring grooves, and the cylinder walls.
On the cylinder walls specifically, the carbon deposits fill the cross-hatch micro-grooves. As the piston moves up and down, the compression rings slide against this carbon-filled surface. The rings polish the carbon progressively smoother with each stroke. Over time, the cross-hatch pattern disappears entirely under a layer of smooth, hard, polished carbon. The surface becomes glassy. The essential oil film that depends on those micro-grooves can no longer be maintained. The ring-to-cylinder seal is severely compromised.
Cylinder glaze and stuck compression rings almost always occur together because they share the same cause. The same carbon that fills the cylinder wall micro-grooves also fills the compression ring grooves, cementing the rings in place. Both problems need to be addressed — and FTC Decarbonizer addresses both simultaneously through the same catalytic combustion process.
Diesel engines are more prone to this. The diesel combustion process typically produces more carbon byproduct, and US diesel fuel quality is generally poor by world standards, exacerbating the carbon byproduct production problem.
How FTC Decarbonizer removes cylinder glaze without a teardown
In the past, the only way to deglaze cylinders was a complete engine teardown: the pistons removed, the cylinder walls mechanically re-honed, and the engine fully reassembled. It's an invasive job and an expensive one.
FTC Decarbonizer is a fuel-borne catalyst added directly to the fuel tank where it synthesizes with the fuel. During the combustion cycle, its catalytic effect lowers the combustion temperature of carbon deposits, causing them to oxidize and burn off during normal engine operation. In the combustion chamber, FTC Decarbonizer works on the cylinder walls, in the cross-hatch micro-grooves, on the compression rings, and in the compression ring grooves.
As the carbon burns off the cylinder wall micro-grooves, the cross-hatch grooves progressively recover. The micro-grooves are restored. The oil film that the rings critically depend on is reinstated. The compression ring seal improves. At the same time, carbon burning off the compression ring grooves causes the rings to expand sufficiently again against the cylinder wall. Both actions of the ring seal recover together.
FTC Decarbonizer works progressively to safely burn off hard carbon in the combustion chamber as the engine operates. If there is substantial carbon buildup, the oxidizing process takes longer than if there is not a lot of carbon buildup. Every engine is different.
No engine disassembly is required. FTC Decarbonizer catalytically enhances the combustion process and oxidizes all hard carbon from the combustion chamber while the engine continues normal operation.
FTC Decarbonizer is perfect for all gasoline and diesel engines and is recommended as part of a regular maintenance routine. If your engine is showing signs of cylinder glazing, when used as directed, FTC Decarbonizer will fix it. Add it to the fuel tank and let the catalytically enhanced combustion process do the work.
Why most cylinder glaze treatments don't work
Solvent-based fuel system cleaners are widely marketed for engine carbon problems. They don't work on cylinder glaze. The carbon that has filled and been polished into the cylinder wall micro-grooves is hard and dense. A brash fuel injector cleaner-solvent passing through the fuel system cannot reach the cylinder wall surface with sufficient concentration or contact time to make any meaningful difference to it. At most, it might just be a brief rinse before it is very rapidly consumed during the combustion process.
Mechanical deglazing — honing or boring the cylinder — works, but it requires a full engine teardown, removal of the pistons, and significant labor. Honing can needlessly remove material from the cylinder wall surface, impacting important tolerances. Re-boring requires an intense teardown, machine shop involvement, and new pistons, etc. Extremely costly.
FTC Decarbonizer works differently because it integrates entirely into the overall combustion process, dramatically enhancing it. During the fuel combustion process, its catalytic effect lowers the combustion temperature of the carbon, causing the deposits to oxidize and burn off as part of the combustion cycle. The combustion flame reaches the cylinder wall surface with every stroke along with FTC Decarbonizer's catalytic effect. It is active with every combustion event, continuously, for as long as it's in the fuel, and for as long as the fuel is combusting. This is how it reaches and removes carbon that a solvent cannot touch.
Is it worth treating before you rebuild?
A gasoline engine overhaul might cost as much as $7,000. A diesel pickup starts at $15,000 to $20,000. Larger trucks, semi-trailers, and other larger diesel-powered equipment easily run $25,000 to $50,000. Mining and large industrial engines reach $400,000 to $500,000.
For an engine that is otherwise in sound mechanical condition, it just makes sense to address the carbon issue before tearing down the engine. FTC Decarbonizer costs a fraction of a mechanical overhaul, and if the cylinder glazing and compression ring seal failure are caused by carbon deposits rather than physical wear or damage, it will fix them.
The distinction matters. Cylinder walls that are dimensionally worn cannot be restored with an additive treatment. But glazed cylinder walls are in most cases dimensionally sound. The surface is compromised by hard carbon, not by wear. Treating the carbon first is a practical and low-cost way to determine which problem you're dealing with. If compression and oil consumption improve after adequate treatment, the cause was carbon build up. If it doesn't, mechanical wear is more likely and a teardown becomes the appropriate next step.
Frequently asked questions about cylinder glazing
What people are saying
“My Peterbilt 389 with the ISX-15 was burning tons of oil and had bad blowby. It's got around 500,000 miles on it. I was going through about 3 gallons of oil every 1400 miles. So I started using the FTC Decarbonizer I got from you, hoping I wouldn't have to get a rebuild. Within about a month the blowby had slowed down a lot! And the oil burning is right down too, now I only need to take 1 gallon of oil with me instead of 3 or 4 gallons. I'm confident that will improve more as I keep using the FTC Decarbonizer. I'll use the Flushing Oil Concentrate in about 3,000 miles when the oil change is due. Hoping that'll tidy up the last of the oil burning. Thanks for your help.”
Steve B, San Diego, CA -- Peterbilt 389, Cummins ISX-15, 500,000 miles
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Ready to try it?
If your engine is showing signs of cylinder glazing, FTC Decarbonizer is the fix. It catalytically enhances the combustion process and oxidizes all hard carbon from the combustion chamber during normal operation, costs a fraction of a teardown, and is perfect for all gasoline and diesel engines, from the smallest to the largest.