Diesel engines are known for their reliability and durability, but even they have their share of problems. One of the most common issues that diesel engine owners face is blowby. Blowby is the escape of combustion gases from the combustion chamber into the crankcase of the engine. It can lead to reduced engine performance, increased oil consumption, and even engine damage if left untreated. In this article, we will discuss how to fix blowby in a diesel engine.
What is Blowby?
Before diving into how to fix blowby, let’s first understand what it is. Blowby is a term used to describe the escape of combustion gases from the combustion chamber into the crankcase of the engine. These gases consist of unburnt fuel, water vapor, and combustion byproducts such as carbon dioxide and nitrogen oxides. Blowby can occur in both gasoline and diesel engines, but it is more common in diesel engines due to their higher compression ratios.
Symptoms of Blowby
Blowby can cause various symptoms that indicate its presence. Some of the most common symptoms of blowby include:
- Increased oil consumption
- Reduced engine performance
- Blue or gray smoke from the exhaust
- Oil leaks from the engine
- Excessive crankcase pressure
- Abnormal engine noises
Causes of Blowby
Blowby can be caused by various factors, some of which include:
- Worn piston rings
- Worn cylinder walls
- Worn valve seals
- Broken or worn piston skirts
- Clogged or damaged PCV valve
- Overheating of the engine
- Incorrect engine oil viscosity
How to Fix Blowby
Step 1: Diagnose the Problem
The first step in fixing blowby is to diagnose the problem. This involves checking the various components of the engine that can cause blowby, such as the piston rings, cylinder walls, valve seals, and PCV valve. A compression test and leak-down test can also be performed to determine the extent of the blowby.
Step 2: Replace Worn Components
If the diagnosis reveals that the blowby is caused by worn components such as piston rings or cylinder walls, they will need to be replaced. This involves removing the engine from the vehicle and disassembling it to access the affected components. The new components can then be installed and the engine reassembled.
Step 3: Clean the Engine
Blowby can lead to the accumulation of oil and carbon deposits in the engine, which can cause further damage and reduce engine performance. Therefore, it is important to clean the engine thoroughly after fixing the blowby. This involves using a degreaser and a pressure washer to remove the accumulated debris and gunk.
Step 4: Use the Correct Engine Oil
Using the correct engine oil is important to prevent blowby from occurring in the future. It is recommended to use an oil with a viscosity that matches the manufacturer’s specifications. Engine oil with a higher viscosity can lead to reduced engine performance, while oil with a lower viscosity can lead to increased oil consumption.
Step 5: Perform Regular Maintenance
Regular maintenance is crucial to prevent blowby from occurring in the future. This includes changing the engine oil and oil filter as per the manufacturer’s recommendations, replacing the PCV valve if it is clogged or damaged, and keeping the engine cool to prevent overheating.
Blowby is a common problem in diesel engines that can lead to reduced engine performance, increased oil consumption, and even engine damage if left untreated. However, by following the steps outlined in this article, you can fix blowby and prevent it from occurring in the future. Remember to diagnose the problem, replace any worn components, clean the engine, use the correct engine oil, and perform regular maintenance.