A friend has a Westerbeke 4kw genset in need of a new exhaust mixing elbow. The existing one has some carbon buildup and a small leak.
The existing one is homemade with a 0.75 in pipe nipple (for the water) welded into a 1.5in pipe nipple (for the exhaust). I thought it would be ok to fab up a new one like the old one, but another friend adamantly insisted that the homemade unit would damage the engine. He went on at great length about the possibility of drawing water into the cylinder thru the exhaust valve on the engine because the exhaust valve is not closed when the pistons begin their intake stroke. I'm not a diesel mechanic, but I wouldn't expect the intake and exhaust valves to overlap enough for this to be a real problem. I thought large overlaps were for high rpm racing engines, not for diesels. Anyone got an opinion? Let me rephrase--anyone got an opinion based on experience?
Since the old homemade unit worked for over 20 years, I am inclined to endorse a homemade over the cost of a factory replacement.
Thanks,
Gil
The existing one is homemade with a 0.75 in pipe nipple (for the water) welded into a 1.5in pipe nipple (for the exhaust). I thought it would be ok to fab up a new one like the old one, but another friend adamantly insisted that the homemade unit would damage the engine. He went on at great length about the possibility of drawing water into the cylinder thru the exhaust valve on the engine because the exhaust valve is not closed when the pistons begin their intake stroke. I'm not a diesel mechanic, but I wouldn't expect the intake and exhaust valves to overlap enough for this to be a real problem. I thought large overlaps were for high rpm racing engines, not for diesels. Anyone got an opinion? Let me rephrase--anyone got an opinion based on experience?
Since the old homemade unit worked for over 20 years, I am inclined to endorse a homemade over the cost of a factory replacement.
Thanks,
Gil