Understanding A Marine Exhaust System
Marine exhausts systems are an important and often overlooked part of a marine engine. Most vessels have a 'wet' exhaust system. Salt water is injected at the riser - the outlet for exhaust from the exhaust manifold. This mixture of exhaust gas and water is then passed through a series of bends until it exits the boat, preferably at the stern.
Exhaust gases mixed with salt water create a highly corrosive compound. This is why exhaust systems are commonly made using non-corrosive components such as nitrile rubber reinforced hose (brown - not green - stripe), galvanized steel, fiberglass or plastic. The purpose of these components, which vary in size and shape depending on the engine size and layout of the engine room, is to prevent hydraulicing of the engine. This is caused when an engine has filled with salt water which has entered via the exhaust and can cause extensive damage if left for more than two hours. Water enters the exhaust from wave action at stern and poor exhaust design. In some ocean conditions, such as a following sea, water can be forced back up the exhaust when the engine is not running. Poorly designed exhausts allow water to flow back and fill the waterlock/muffler box then up the hose into the exhaust manifold, through the exhaust valves and into the combustion chamber. With the engine full of water the engine cannot crank over as it is cannot compress water.
You will know your engine is hydrauliced if it will not turn over - generally after a long sailing period - and you have removed the starter motor and ensured it works. To remove water from inside the combustion chambers, first remove all injectors, crank engine over to blow water out, refit injectors, bleed injector lines, and start. Then leave motor running until exhaust sorted out.
Check to see that the riser is not coked up or corroded - a common problem. To check the exhaust riser remove the exhaust hose from the riser (often a difficult procedure) and look up the pipe to see if it is restricted by exhaust/salt build up. If build up is excessive the riser will have to be removed to check the engine end of the pipe. Coke can be scraped out to provide a short term fix although often the riser will have to be replaced. There are aftermarket systems which vary in quality. Make sure you fit the right design for the application.
Ensure your water-lock is low enough and big enough to hold all the water in exhaust system. Is there a gooseneck or central vertical loop in the exhaust hose at the transom exit? Is there a siphon break and is it functioning properly - no leaking valves?
Exhaust gas is poisonous and can cause sea sickness and headaches. Replace any faulty parts immediately. Use double hose clamps on each joint or, preferably, super clamps, bolt style, and exhaust cement if need be. Hot sections should be lagged with fiberglass tape to prevent burns.
Beware of asbestos lagging. Many older vessels and marine engine installations had exhaust systems that were lagged with asbestos tape and rope. Asbestos sound-proofing was also common in older boats.
3:19 AM | Labels: exhaust, marine, System, Understanding | 0 Comments
Include a marine exhaust system
Marina are exhausted is an important marine and often overlooked. Most ships have a "wet" exhaust system. The salt water is injected into the lift - the removal of the escape of exhaust gases. This mixture of gas and water has passed through a series of curves, to miss the boat, preferably in the back.
The exhaust gas is mixed with salt water, a highly corrosive compound. Therefore, the exhaust systems are often using non-corrosiveComponents such as nitrile rubber reinforced with glass fiber tube (Brown - Banda - not green), galvanized steel or plastic. The purpose of these elements, which vary in size and shape depending on the size of the engine and the design of the engine room is to avoid hydraulicing engine. This is an engine of salted water, drain and can cause considerable damage if it occurs more than two hours to fill. The water comes from the wave at the rear exhaust and poordrainage design. Under certain conditions of the sea like a sea below, the water can back up the exhaust pipe when the motor is not enforced. Poorly designed exhaust the water to flow back and fill the box of water intake / exhaust pipe and valves in the combustion chamber and exhaust discharge. With the engine full of water can not run the engine and you can not compress water.
You know that your engine is not running as SYSTEM -Usually after a long veil - and they removed the starter and make sure it works. To remove water from inside the combustion chamber for the first time all the injectors to operate the engine in the water, mount the nozzles rate, blood lines and how the injector. Then allow the engine until the leak fixed.
Verify that the elevator is not clogged or corroded - a common problem. To verify the vertical exhaust pipe, remove the jack post (often long and difficult)and look at the exhaust / salt build-up is limited. When construction of the column is too large to be removed for the motor to check the line. Coca-Cola can be scraped to obtain a short-term solution, but often the result must be replaced. There are systems in different parts of the quality. Make sure you put a good application design.
To block the water is low enough and large enough to hold all the water in the exhaust system. There is aA gooseneck or central vertical loop at the end of the hose on the front page? There is a trap and its smooth operation - without valves leak?
Exhaust is toxic and can cause dizziness and headaches. Replaced immediately. Use double hose clamps on each joint cement or, preferably, super clamps, bolt style exhaust, if necessary. sections of fiberglass hot after the band to prevent burns.
Beware of asbestos ago. Many large vessels andmarine engine installations had exhaust systems that have remained with asbestos tape and rope. Sound insulation of asbestos in old boats.
11:19 PM | Labels: exhaust, include, marine, System | 0 Comments