What Can Cause High Crankcase Pressure In A Diesel Engine?

Venting a conventional V-8 engine isn’t difficult. Usually, all that’s required is a breather atop each valve cover. Of course, replacing one with a PCV valve to introduce some vacuum into the system and redistribute the unburned hydrocarbons back into the engine via the carburetor or throttle body results in a cleaner and more environmentally friendly alternative. Supercharged applications, on the other hand, can be finicky. When employing a standard push-in style breather, increased pressure in the crankcase might produce blow-by, coating that trick engine compartment in a fine mist of fuel-oil. Adding a PCV valve is an excellent idea until the engine is boosted, at which point the internal check valve is forced shut, leaving the valve useless. Instead of pulling new air into the breather and using the PCV valve to relieve the crankcase pressure, the internal pressure is vented out the breather, potentially leading in another greasy blow-by incident. When the engine is under load or at high rpm, pressure builds up quickly and needs to be alleviated the most.

Can a clogged air filter cause high crankcase pressure?

The Walker and Racor CCVs use slightly different techniques, despite the fact that they both work in the same way. The Walker system has a single air filter and coalescing filter located on the turbo, but the Racor system has a separate coalescing filter mounted distant from the turbo inlet.

Closed systems require limited, but crucial, maintenance. The air filter on the outside must be cleaned or replaced once a year or every 250 hours of operation.

The engine will be starved for air if the air filter becomes blocked, and performance will suffer as a result. The vacuum in the crankcase will grow until the regulator takes control and generates a bypass to relieve the pressure. While most systems have a restriction indicator to warn you to this condition, regardless of whether excessive restriction is shown, you should always follow the prescribed service intervals.

Eliminate your air filter and lightly brush it to remove any loose particulates before servicing it. After that, spritz on the manufacturer’s cleaning solution and let it sit for 10 to 15 minutes. Finally, using fresh water under low pressure, rinse the air filter from the inside out. After allowing the filter to dry, add the filter oil that came with the service kit and reinstall the filter.

Can too much oil cause crankcase pressure?

To understand why overfilling your engine oil is a bad idea, it’s helpful to start with some basic information.

Engines are made up of hundreds of finely constructed pieces that work together at high speeds and temperatures, all of which require oil for optimum lubrication and smooth operation. Oil is added to an engine’s crankcase via the “Oil” cap beneath the hood by you or your mechanic. When the engine is not operating, the oil sits in the oil pan. When you start the engine, the oil flows throughout it and passes through an oil filter, which filters out impurities that could cause damage.

The level in the oil pan grows too high when too much oil is applied. This permits the crankshaft, a fast-moving lobed rod, to come into touch with the oil and aerate it. The end result is a foamy, frothy fluid that can’t lubricate the engine adequately. Consider it your engine’s method of converting cream to whipped cream. Nobody wants their engine to be lubricated with whipped cream.

The additional oil also causes excessive pressure inside your engine, which will try to escape through various gaskets and seals. If one or more of them fails, leaks will occur, requiring costly repairs.

How do you fix excessive Blowby?

“FTC Decarbonizer is added to the diesel at each fill to prevent engine blow by, and then you simply drive the engine clean! The decarbonization procedure is delicate and gradual, but effective, cleaning turbos and DPFs in the process.”

To restore full cleanliness to the lower piston rings, most engines will need to be cleaned from the oil side as well. This entails flushing the engine with Flushing Oil Concentrate. It targets hard, baked-on deposits and engine sludge with detergents and, according to the producers, restores the engine “throughout “as new clean”

The longer you ignore blow-by, the more carbon builds up in your engine. Black smoke and oil soot levels are rising! Performance and fuel efficiency decline. Excessive carbon on pistons can cause quick wear. Carbon buildup in the ring grooves causes the majority of fractured piston rings. By cleaning the engine up, and more importantly, keeping it clean, the chance of engine failure is considerably reduced!

Engine blow by reduced

The images below are from a decade ago, when Caterpillar D11R dozers were working in Queensland’s Bowen Basin. The rebuild life was estimated to be around 11,000 hours. Many failures occurred as a result of excessive carbon buildup, with some failures occurring after only 3000-4000 hours. Rebuild intervals were typically 8,000-10,000 hours. FTC Decarbonizer was used by one 10-piece fleet that stood out! At 15,000 hours, the first engine was pulled down and determined to be in great condition. They eventually settled on 18,000-hour rebuild intervals.

Turbochargers, EGR valves, and diesel particulate filters are all clogged by increased exhaust soot. Turbo seals are chewed away by increased oil soot. Blowby is responsible for a lot of disastrous failures.

Engine blow by difficulties can be resolved, resulting in engines that are less stressed, more efficient, and last longer. The key to extending the life of Euro V emission-controlled engines is to burn the fuel cleanly for low exhaust soot and low oil soot levels.

What are the symptoms of a bad crankcase breather hose?

Poor fuel economy, the Check Engine Light going on, engine misfires while idling, and engine noise are all common symptoms.

How do I know if my crankcase breather is bad?

Excessive oil consumption, oil leaks, a clogged breather filter, and a decline in overall performance are all indicators of a defective PCV valve.

What happens if crankcase breather is clogged?

Another symptom that a crankcase breather isn’t working properly is a sluggish engine. Vacuum leakage from a clogged breather can result in an improper air-fuel ratio. At low engine speeds, you’ll notice a reduction in overall power and acceleration. This problem, if left unaddressed, can result in a buildup of corrosive acid, which can destroy the entire engine and result in a full loss of power.

What is normal crankcase pressure for a diesel engine?

Most diesel engines have a maximum permitted crankcase pressure of 1.0″ H2O to 4.0″ H2O. For diesel engines, contaminated crankcase emissions can be a major issue.