No water seems to be coming out of the exhaust. Water flows thru the intake value after opening the seacock. Checked the impeller and its fine. One guy had a problem with exhaust buildup --- but where can you get at the exhaust pipe to clean it. Mixing elbow and heat exchanger and thermostat were also mentioned. Im not very mechanical. How do you check them? Vinegar or de-scaler to clean the insides? Thanks Richard
Engine over heat still not resolved
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impeller turning?
Hello, It would help if you provided the engine make and model. Is the impeller turning? It is possible that the raw water pump has broken. Then, even with a good impeller, no water would be pumped. If the impeller is turning, I would remove one end of the heat exchanger, or maybe just remove the zinc, and see if water is making it that far. From the heat exchanger the water goes to the exhaust and then the waterlift muffler. You should be able to trace the flow. Good luck, Barry
Hello, It would help if you provided the engine make and model. Is the impeller turning? It is possible that the raw water pump has broken. Then, even with a good impeller, no water would be pumped. If the impeller is turning, I would remove one end of the heat exchanger, or maybe just remove the zinc, and see if water is making it that far. From the heat exchanger the water goes to the exhaust and then the waterlift muffler. You should be able to trace the flow. Good luck, Barry
Does your engine have a radiator cap?
If so it is a fresh (anti really) water cooled engine. if it does not then it is a raw (sea) water cooled engine. The radiator cap will not be on a radiator it will be somewhere around the engine or on a plastic bottle. Raw water cooled engines have to warm up before water is released to the exhaust. There is a small bypass hole in the thermostat that keeps the exhaust cool till that happens.
If so it is a fresh (anti really) water cooled engine. if it does not then it is a raw (sea) water cooled engine. The radiator cap will not be on a radiator it will be somewhere around the engine or on a plastic bottle. Raw water cooled engines have to warm up before water is released to the exhaust. There is a small bypass hole in the thermostat that keeps the exhaust cool till that happens.
Two other ideas
1. Among the interesting little “tidbits” of information that I’d remembered reading about on the website had to do with cleaning out the raw water intake with a dinghy foot pump. On a nice mid-winter March sail with Ken Heyman, our treasurer who was here visiting, we had just left the South Beach Marina and were motoring over to see the “Lady Washington,” one of the tallships that regularly visits the Bay Area and has cannonball encounters of the close kind with fellow tallships. Since it was cold out, there seemed to be a bit more white smoke from the exhaust than usual, which I attributed to the lower air temperature. Upon checking the temperature gauge, we noted it was pegged and stopped the engine immediately. Ken and I went through a checklist of actions we could take. Sailing back to the marina was not among them, since there was no wind and the end of the ebb was setting us north towards the Bay Bridge. Thru hull strainer clear – check. Raw water entering – check, but a trickle and less than expected. Raw water pump impeller in one piece – check. Raw water pump turning – check. Spare raw water pump gasket to replace cover – check. Temperature gauge working properly – check. Hoses and thru hull clear – hmm… We got the dinghy foot pump out from the lazarette, replaced the strainer and opened the seacock. Because the arrangement of the hoses and the strainer on “Aquavite” aren’t configured to connect the pump there, we removed the hose from the raw water pump and used the dinghy pump at that end of the hose. That turned out to be actually be easier than trying to work under the head sink. There was significant resistance at first, but after setting the three way valve on the foot pump to a higher pressure setting, the pump started working. Whatever had been clogging either the thru hull or the line was flushed out. Once everything was reassembled, we started the engine and all was well. Lesson Learned: It pays to read the material on the [C34] website because you just never know when you’ll be faced with an insurmountable problem only to find out that one of our skippers had “been there – done that” and had most importantly reported it for all of us to know. Thanks to Ken for his analytical assistance! 2. Remove your HX and check the tube going into it from the raw water pump. Even if the tubes are fine, sometimes this tube gets cacked up with salt deposits.
1. Among the interesting little “tidbits” of information that I’d remembered reading about on the website had to do with cleaning out the raw water intake with a dinghy foot pump. On a nice mid-winter March sail with Ken Heyman, our treasurer who was here visiting, we had just left the South Beach Marina and were motoring over to see the “Lady Washington,” one of the tallships that regularly visits the Bay Area and has cannonball encounters of the close kind with fellow tallships. Since it was cold out, there seemed to be a bit more white smoke from the exhaust than usual, which I attributed to the lower air temperature. Upon checking the temperature gauge, we noted it was pegged and stopped the engine immediately. Ken and I went through a checklist of actions we could take. Sailing back to the marina was not among them, since there was no wind and the end of the ebb was setting us north towards the Bay Bridge. Thru hull strainer clear – check. Raw water entering – check, but a trickle and less than expected. Raw water pump impeller in one piece – check. Raw water pump turning – check. Spare raw water pump gasket to replace cover – check. Temperature gauge working properly – check. Hoses and thru hull clear – hmm… We got the dinghy foot pump out from the lazarette, replaced the strainer and opened the seacock. Because the arrangement of the hoses and the strainer on “Aquavite” aren’t configured to connect the pump there, we removed the hose from the raw water pump and used the dinghy pump at that end of the hose. That turned out to be actually be easier than trying to work under the head sink. There was significant resistance at first, but after setting the three way valve on the foot pump to a higher pressure setting, the pump started working. Whatever had been clogging either the thru hull or the line was flushed out. Once everything was reassembled, we started the engine and all was well. Lesson Learned: It pays to read the material on the [C34] website because you just never know when you’ll be faced with an insurmountable problem only to find out that one of our skippers had “been there – done that” and had most importantly reported it for all of us to know. Thanks to Ken for his analytical assistance! 2. Remove your HX and check the tube going into it from the raw water pump. Even if the tubes are fine, sometimes this tube gets cacked up with salt deposits.
Check things one at a time
in sequence. You can use a cordless drill with a socket that fits onto the front of the pump to turn it (remove the drive belt from the pulley temporarily). If you are sure you have water into the pump, unhook or loosen the outlet and see if there is water coming out there. If so, unhook or loosen the hose at the next location which is the exhaust manifold on my engine (Yanmar 35 hp). If there is pressure there, check the raw water outlet at the outlet (rear) of the manifold. Then on to the elbow water inlet fitting. If there is water getting there and it is not going into the exhaust elbow, that is likely the problem. Stick a screwdriver into the hose fitting and twist it around to see what you get out. It may be full of carbon and rust. You may get enough of it out to allow water to flow or it may be clogged around the exhaust side too much. If it comes clean enough to allow water flow, you still will need to deal with the elbow itself by cleaning or replacing it. If you get a new one, get the nipple to go with it. You can remove the elbow but it is no easy job if it is rusted on. You will need a pipe wrench or two and maybe a long pipe to fit on one of them for more leverage. Remove the exhaust hose first and stick a screwdriver up inside and see what comes out. You may be able to clean it out enough that way to get some water to flow. Removing the elbow is fairly obvious with the exception of the nipple which has regular thread on one end and reverse thread on the other. See if you can loosen the elbow at the lower threaded part of the nipple. That is the regular thread so it should loosen in the normal direction. Once you get it off, you can chisel out the carbon and rust but be careful not to break the metal casting. Just get out the crud and then you will be able to get water to pass through it. If you want to replace it with black pipe model like I did, check the archives for what I did a couple of years ago for about $20. Mine is still going strong with no problems. When you reattach it, use a lot of non teflon high temperature anti-sieze compound on the pipe threads.
in sequence. You can use a cordless drill with a socket that fits onto the front of the pump to turn it (remove the drive belt from the pulley temporarily). If you are sure you have water into the pump, unhook or loosen the outlet and see if there is water coming out there. If so, unhook or loosen the hose at the next location which is the exhaust manifold on my engine (Yanmar 35 hp). If there is pressure there, check the raw water outlet at the outlet (rear) of the manifold. Then on to the elbow water inlet fitting. If there is water getting there and it is not going into the exhaust elbow, that is likely the problem. Stick a screwdriver into the hose fitting and twist it around to see what you get out. It may be full of carbon and rust. You may get enough of it out to allow water to flow or it may be clogged around the exhaust side too much. If it comes clean enough to allow water flow, you still will need to deal with the elbow itself by cleaning or replacing it. If you get a new one, get the nipple to go with it. You can remove the elbow but it is no easy job if it is rusted on. You will need a pipe wrench or two and maybe a long pipe to fit on one of them for more leverage. Remove the exhaust hose first and stick a screwdriver up inside and see what comes out. You may be able to clean it out enough that way to get some water to flow. Removing the elbow is fairly obvious with the exception of the nipple which has regular thread on one end and reverse thread on the other. See if you can loosen the elbow at the lower threaded part of the nipple. That is the regular thread so it should loosen in the normal direction. Once you get it off, you can chisel out the carbon and rust but be careful not to break the metal casting. Just get out the crud and then you will be able to get water to pass through it. If you want to replace it with black pipe model like I did, check the archives for what I did a couple of years ago for about $20. Mine is still going strong with no problems. When you reattach it, use a lot of non teflon high temperature anti-sieze compound on the pipe threads.
Lots of possibilities
Some of these suggestions may not apply to your engine: 1) Check raw water intake- is thruhull valve open and is the filter unclogged? 2) Check raw water hoses- are they old and tired, possibly kinked or clogged? 3) Remove the thermostat and check that it works by throwing it in some boiling water. 4) Check that you have the right thermostat for your model engine. 5) Look at the parts diagram for the water pump and check that yours has the same parts. 6) Test the impeller turns when the engine turns. Get the manual for your engine and read it before you run the engine again.
Some of these suggestions may not apply to your engine: 1) Check raw water intake- is thruhull valve open and is the filter unclogged? 2) Check raw water hoses- are they old and tired, possibly kinked or clogged? 3) Remove the thermostat and check that it works by throwing it in some boiling water. 4) Check that you have the right thermostat for your model engine. 5) Look at the parts diagram for the water pump and check that yours has the same parts. 6) Test the impeller turns when the engine turns. Get the manual for your engine and read it before you run the engine again.
FWIW
I went through an overheating issue and did everything suggested and the problem ended up being the exhaust hose was kinked underneath the floor. (my engine is in the center of the boat) My old boat had a check valve between the exhaust elbow and muffler, they can go bad too.
I went through an overheating issue and did everything suggested and the problem ended up being the exhaust hose was kinked underneath the floor. (my engine is in the center of the boat) My old boat had a check valve between the exhaust elbow and muffler, they can go bad too.
Check raw water strainer
Had a similiar problem last weekend. I had cleaned out our raw water strainer and didn't fully retighten the wing nuts holding the cap in place when reassembling. It had lost suction, I guess. During troubleshooting, we saw the small water leak from the strainer assembly. We repositioned the strainer and retightened the nuts and VOILA, water spurted from the exhaust. Last year we had to replace the mixing elbow because of no exhaust water so I knew THAT couldn't be the problem so soon.
Had a similiar problem last weekend. I had cleaned out our raw water strainer and didn't fully retighten the wing nuts holding the cap in place when reassembling. It had lost suction, I guess. During troubleshooting, we saw the small water leak from the strainer assembly. We repositioned the strainer and retightened the nuts and VOILA, water spurted from the exhaust. Last year we had to replace the mixing elbow because of no exhaust water so I knew THAT couldn't be the problem so soon.
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