Generally, people don’t understand the purpose of exhaust flanges in the engine, unless they need to fix it. However, it is essential for the exhaust system and it makes the system efficient. The main purpose of flanges is to make out the hot gases through the exhaust system without obstruction.
Moreover, flanges connect the exhaust manifold to the exhaust pipe. Normally, these are connected with a rubber gasket that seals the exhaust pipe with the manifold and avoids leaks. If the exhaust system has leaked it causes a lot of noise and car performance will go down. To fix exhaust leak at flange, either you need to repair the exhaust flange leak or replace the old flange with a new one. The flange repair is a complicated process and needs special attention.
In this article, I will guide you on how to fix exhaust leak at flange.
What is an Exhaust System?
Automobile exhaust systems caries away harmful gasses like carbon monoxide, nitrogen oxide, and hydrocarbon from the system. An effective exhaust system provides efficient fuel economy and is environmentally friendly. Let’s look at some important components of an exhaust system.
1. Exhaust Manifold
The manifold collects all the exhaust gases from each cylinder into one point. Normally, it is of cast iron, and it connects engine exhaust ports. If the exhaust gases cannot go out through the exhaust manifold due to hindrance, the manifold glows to red duet to overheated.
2. Exhaust pipe
The major purpose of the exhaust pipe is to allow gasses to escape from the system without obstruction. Obstruction in pipes causes a problem in car effectiveness.
3. Exhaust Flanges
Exhaust flanges are the small part of the exhaust system that connects the pipe to the manifold. Moreover, if there is a leak in the flanges, car performance will be compromised. The leaks are hazardous and extremely toxic and can cause damage to the vehicle's performance.
4. Muffler
When emissions pass through the exhaust system muffler reduces the sound of the car engine. Additionally, for leaks in the muffler, muffler sealer reduces the sound of the engine.
5. Hangers
Hangers are known as exhaust support. They secure and support exhaust pipes that are present underneath the car.
6. Catalytic Converter
The catalytic converter filters the toxic byproduct that comes exhaust system.
How to fix exhaust leak at flange?
When you start the engine and notice a loud sound coming out the exhaust. It is the main proof of exhaust leaks. If you hear hissing or tapping noise, it indicates the manifold leaks. Moreover, if you hear a rumbling sound that is much louder than normal, it indicates an exhaust flange leak. Let us look at the exhaust repair flange process.
Step 1: Turn off the engine
After identifying the problem turn off the engine and let it cool for several hours. It is because the exhaust pipe is too hot.
Step 2: Clean the location of the leak
Before cleaning use rubber gloves and glasses to avoid dirt into your eyes and hands. Use sandpaper to remove material from the surface of the leak. Moreover, after scrubbing the surface apply acetone to clean the damaged area.
Step 3: Use exhaust seal
Usually, the hole in the pipe is small, and by using exhaust tape it is easily fixed. Moreover, if there is a gap between the flanges use adhesive sealant to cover the gap. It is not a permanent solution. However, it works well.
Replacement exhaust flange
Generally, all automobile has flange connector that connects exhaust parts like mufflers, exhaust manifold, the catalytic converter. The exhaust manifold gasket seals the gap between the exhaust port and exhaust manifold. It not only reduces the sound of the engine but also stops escaping harmful gases. Most exhaust manifold gaskets don’t need a sealant. However, some gasket comes with their sealant. Exhaust manifold gasket sealant can burn due to extreme heat in the header interference.
Let’s look at the replacement process:
Step 1: Inspect the pipe with a leak
The exhaust manifold flange gasket connects the front pipe. However, the rear pipe connects with the exhaust pipe. To access the leak, disconnect the rear flange connection.
Step 2: Identify and remove the bolts and screws
The bolts and screws secure the flange from damage. Moreover, when the car is jacked up, bolts and screws are easily identified. Take a ratchet to unscrew or loosen the screw. Remove all the bolts, except bolts that are on the sides of the header.
Step 3: Separate the flange connection
Hangers provide support to the exhaust pipe. Use a hanger tool to release hangers that are near the flange. Additionally, disconnect every connection on the pipe and manifold.
Step 4: Clean the flange connector
Use a clean cloth to clean the surface. If the exhaust pipe is rusty use sandpaper to scrub the rust away and also unclog the catalytic converter to get better fuel economy.
Step 5: Remove the old flange
Sometimes old flange gets stuck, use a knife or flat metal piece to remove the stuck ones. Furthermore, scrape the dirt off for proper seal. Apply automobile sealant on both sides of the gasket for good grip.
Step 6: Connect the new flange gasket
Properly fit the new flange to avoid any leaks. Now reconnect the connector, hangers, screws, and bolts. Start the automobile and check for any leaks. If you notice any sound re-tighten the hardware again. Sometimes gasket requires welding. Weld-on exhaust flange requires mechanic assistance because it is not an easy task
How to Identify exhaust leak at flange?
Before repairing let us discuss how to identify exhaust leaks in the exhaust system. Moreover, the best way to inspect exhaust leaks is by physically monitoring the exhaust manifold, exhaust pipe, and flanges. These are the sign of exhaust leaks.
1. Loud engine noise
2. Decreased fuel economy
3. Vibrating gas pedal
4. Gas smell
5. Reduced acceleration and power of an automobile
6. Engine overheating
FAQ
1. How much does it cost to fix an exhaust flange leak?
Generally, exhaust flange repair requires 2 to 3 hours. Some automobile repair shops charge between $80 to $100 per hour. So approximately the cost of repair is $160 to $ 300.
2. Can you use JB Weld on the exhaust flange?
No, J-B Weld is not for repairs in extreme temperatures and the combustion chamber is extremely hot. Most experts don’t recommend using J-B weld for exhaust manifold, pipe, and catalytic converter repairs.
3. Can you drive with a manifold leak?
Yes, driving with an exhaust leak is not safe because fumes in the chamber contain toxic gases like carbon monoxide. The leaks shouldn’t be ignored because it a safety hazard.
4. Will an exhaust leak throw a code?
Commonly, it is rare for an exhaust leak to throw a code. However, it depends upon the location of the exhaust and O2 sensor.
5. What does an exhaust leak sound like?
An exhaust leak sounds like ticking or puffing. However, the rumbling sound louder than usual is the indicator of the leaks.
Conclusion
The exhaust system is one of the most important systems. It makes toxic gas away from the car and improves the fuel economy. This article answers the question how to fix exhaust leak at flange? Although flanges don’t seem to be an important part of an exhaust system. However, it’s essential for the health of the system.
If the exhaust system is not working well car consumes more fuel, makes noises and the engine is not efficient. Regular checks for leaks can help in avoiding this problem.