Is anyone else familiar with the oddities of a Hunter Legend 40 exhaust system?
It has a lift muffler underneath the engine so you can't replace without lifting engine. Wraps back around the top of engine to an inverted trap then down underfloor, thru centerline berth, in a pan beam up out of beam into a low cabinet, thru stern bulkhead over the diesel fuel tank, then out a below waterline thru hull. A super long and complex 2" hose run defying all standard design guides. But it's worked for 30+ years with too much backpressure the engine runs hot and smokes.
The water is not cold as it first runs thru oil cooler and then coolant exchanger up to an inverted U with air vent which is actually a non-vented brass bolt. Then it necks down into an inverted U mixing elbow from a 3 cylinder engine by necking down from 1" to a 1/2" side port on the mixing elbow (not a good flow pattern to mix with exhaust. I'm wondering if they did that on purpose to restrict waterflow to reduce backpressure??? Say it ain't so and it's just a crappy design. HDI Marine sells full size mixing elbows with a full 1" port on the heel.
So, who can tell me why they designed/installed it this way. The industry pro's I've contacted can't figure out how it works because the 2" hose is so long and has multiple traps for two high points as well as sagging hose.
I need to replace as cooked the muffler, but looking to simplify and reduce backpressure. If you have appreciate the feedback on how and if it worked well. Thanks.
It has a lift muffler underneath the engine so you can't replace without lifting engine. Wraps back around the top of engine to an inverted trap then down underfloor, thru centerline berth, in a pan beam up out of beam into a low cabinet, thru stern bulkhead over the diesel fuel tank, then out a below waterline thru hull. A super long and complex 2" hose run defying all standard design guides. But it's worked for 30+ years with too much backpressure the engine runs hot and smokes.
The water is not cold as it first runs thru oil cooler and then coolant exchanger up to an inverted U with air vent which is actually a non-vented brass bolt. Then it necks down into an inverted U mixing elbow from a 3 cylinder engine by necking down from 1" to a 1/2" side port on the mixing elbow (not a good flow pattern to mix with exhaust. I'm wondering if they did that on purpose to restrict waterflow to reduce backpressure??? Say it ain't so and it's just a crappy design. HDI Marine sells full size mixing elbows with a full 1" port on the heel.
So, who can tell me why they designed/installed it this way. The industry pro's I've contacted can't figure out how it works because the 2" hose is so long and has multiple traps for two high points as well as sagging hose.
I need to replace as cooked the muffler, but looking to simplify and reduce backpressure. If you have appreciate the feedback on how and if it worked well. Thanks.
