I recently removed and cleaned my heat exchange unit (on a Universal M35 B). After putting it back on, I also changed the thermostat and temperature sending unit for the heat gauge as it seemed to be running cold. This seemed to fix this problem and the engine ran at about 165 degrees. (I had a little problem bleeding the air out because there is no bleeder valve, so what I did was run the engine and loosten one of the temp sending units until nothing but coolant came out.) Yesterday I took the boat out. I motored about 45 minutes up the Oakland-Alameda estuary and then raised the sails and sailed for several hours. On my return the wind died down so I turned on the motor and motor sailed. I ran the motor at about 2400 rpm's for about an hour. Every time I looked, the temperature was still around 165 or so. After about an hour the water temp alarm went off. I shut off the engine after a quick look at the gauge. My memory was that it was still at 165 or so, but maybe I was looking at it wrong since I was stressing a little. AFter about 5 minutes, I checked the gauge and it was reading close to 180. The gauge showed the temperature gradually dropping, until it was below 120, as I slowly sailed down the estuary. However, when I turned on the engine, the alarm still went off. This was after the engine had be shut down for about an hour or hour and a half. Today, I checked the connection from the temp unit that goes to the alarm and it seems fine. I didn't crank up the engine, but when I turned the key on the alarm did not go off (as opposed to last night). What I can't figure out is (1)Why the gauge seemed to read normal but the alarm still went off, even after over an hour. (2)Why it took several hours of running the engine before the alarm went off. Any ideas?
water temp alarm
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You need one of these:
What you need is an Infrared (IR) Thermometer. I had a similar problem and my Raytek MT4 diagnosed the problem as the gauge not the sending unit in about 30 seconds. By simply aiming the laser beam, at the thermostat housing, where the sending unit resides, I quickly discovered it was running between 176 & 181 degrees. This is exactly where it should be running based on my 180 degree thermostat. More often than not it's the gauge not the sending unit. You could still have some air trapped in there though.... I would never own a boat or a car without also owning an IR thermometer!! PS- If you need a new temp gauge the Teleflex gauges are all Universal uses and you can buy one at WM right off the shelf for about $25.00 - $30.00 as opposed to paying BIG $$$ for the one that actually says Universal on it. Here's the gauge I used on my Westerbeke which uses the same instrument panel as the M35 (unless it's a Catalina). If it's a Catalina with the pedestal mounted gauges they just use a different Teleflex gauge style as opposed to the Teleflex Red series.. Teleflex Red Temp Gauge: http://www.boatersworld.com/product/348500059.htm Infrared Thermometer Raytek MT4: http://www.testequipmentdepot.com/raytek/noncontact/mt2andmt4.htm PS Again: John you should have a bleeder petcock in your thermostat housing right next to the temp sending unit. Look on page 45 of your M35B parts manual or go here and look at it: http://www.westerbeke.com/Online_Manuals/201021_m25xpb_m35b_m40b_parts_man.pdf The part is listed as part# (011471) / description PECCOCK / REMARKS 1/8 inch NPT EXT SEAT (BRASS) This is on page 46. If you currently have a plug there remove it and replace it with a 1/8 NPT petcock...
What you need is an Infrared (IR) Thermometer. I had a similar problem and my Raytek MT4 diagnosed the problem as the gauge not the sending unit in about 30 seconds. By simply aiming the laser beam, at the thermostat housing, where the sending unit resides, I quickly discovered it was running between 176 & 181 degrees. This is exactly where it should be running based on my 180 degree thermostat. More often than not it's the gauge not the sending unit. You could still have some air trapped in there though.... I would never own a boat or a car without also owning an IR thermometer!! PS- If you need a new temp gauge the Teleflex gauges are all Universal uses and you can buy one at WM right off the shelf for about $25.00 - $30.00 as opposed to paying BIG $$$ for the one that actually says Universal on it. Here's the gauge I used on my Westerbeke which uses the same instrument panel as the M35 (unless it's a Catalina). If it's a Catalina with the pedestal mounted gauges they just use a different Teleflex gauge style as opposed to the Teleflex Red series.. Teleflex Red Temp Gauge: http://www.boatersworld.com/product/348500059.htm Infrared Thermometer Raytek MT4: http://www.testequipmentdepot.com/raytek/noncontact/mt2andmt4.htm PS Again: John you should have a bleeder petcock in your thermostat housing right next to the temp sending unit. Look on page 45 of your M35B parts manual or go here and look at it: http://www.westerbeke.com/Online_Manuals/201021_m25xpb_m35b_m40b_parts_man.pdf The part is listed as part# (011471) / description PECCOCK / REMARKS 1/8 inch NPT EXT SEAT (BRASS) This is on page 46. If you currently have a plug there remove it and replace it with a 1/8 NPT petcock...
Good stuff from Maine Sail
Because you messed with it I would diagnose your problem as a faulty sending unit. Check to make sure the lead is not shorted on anything. The R&R you did may have caused it to fail. Expansion from engine heat may have caused the failure to delay. Remove the lead and see if the alarm continues to sound. Ground the lead to see if it sounds(it should). Check the resisitence of the sending unit with an ohmmeter(lead disconnected and engine cold). Also make sure this is not your low oil pressure alarm. That could be much worse. Tim R.
Because you messed with it I would diagnose your problem as a faulty sending unit. Check to make sure the lead is not shorted on anything. The R&R you did may have caused it to fail. Expansion from engine heat may have caused the failure to delay. Remove the lead and see if the alarm continues to sound. Ground the lead to see if it sounds(it should). Check the resisitence of the sending unit with an ohmmeter(lead disconnected and engine cold). Also make sure this is not your low oil pressure alarm. That could be much worse. Tim R.
I will also add..
I will also add to what Tim said. On that engine there are two temp monitoring devices. The first is part #7 and it's the "Temperature Sending Unit". This sends a signal directly to the gauge and is independent of the alarm system. The second is part #2 and it's a "Water Temperature Alarm" switch which is set to go off if the temp gets to high. Diagnose the operating temperature first before you rush to judgment. If the engine is running at 180 then the alarm could be one of the other warning devices such as oil pressure..
I will also add to what Tim said. On that engine there are two temp monitoring devices. The first is part #7 and it's the "Temperature Sending Unit". This sends a signal directly to the gauge and is independent of the alarm system. The second is part #2 and it's a "Water Temperature Alarm" switch which is set to go off if the temp gets to high. Diagnose the operating temperature first before you rush to judgment. If the engine is running at 180 then the alarm could be one of the other warning devices such as oil pressure..
thanks, and...
Thanks for the speedy replies. Some additional thoughts: First, I double checked to make sure it wasn't the low oil pressure. No, that's not it. Second, as for a bleeder petcock: The diagram in the manual shows one temp sending unit - for the alarm, and then the petcock. Where the diagram shows the petcock is where my temp sending unit for the gauge is. Second, I haven't had problems with the gauge up until now, so my question is why should the gauge suddenly go bad now? In any case, why would it be overheating, but only after running for several hours? If there's still air somewhere in they system, is it possible that it could move from one part to another and only affect the circulation after this time?
Thanks for the speedy replies. Some additional thoughts: First, I double checked to make sure it wasn't the low oil pressure. No, that's not it. Second, as for a bleeder petcock: The diagram in the manual shows one temp sending unit - for the alarm, and then the petcock. Where the diagram shows the petcock is where my temp sending unit for the gauge is. Second, I haven't had problems with the gauge up until now, so my question is why should the gauge suddenly go bad now? In any case, why would it be overheating, but only after running for several hours? If there's still air somewhere in they system, is it possible that it could move from one part to another and only affect the circulation after this time?
How did you clean your HE?
Did you have it dipped or did you try and clean it by running a hanger through it? You may have knocked some crud loose that is clogging your system. Like Maine Sail said, first confirm that your coolant is really that hot. Tim R.
Did you have it dipped or did you try and clean it by running a hanger through it? You may have knocked some crud loose that is clogging your system. Like Maine Sail said, first confirm that your coolant is really that hot. Tim R.
Temp Sending Unit and gage
Shouldnt the temp sending unit be matched to the gage? On my Catalina 30, I had a Universal Diesel and had a similar problem. The dealer told me to change the sending unit and gage at the same time. Tony B
Shouldnt the temp sending unit be matched to the gage? On my Catalina 30, I had a Universal Diesel and had a similar problem. The dealer told me to change the sending unit and gage at the same time. Tony B
John..
"Second, I haven't had problems with the gauge up until now, so my question is why should the gauge suddenly go bad now?" and... "I recently removed and cleaned my heat exchange unit (on a Universal M35 B). After putting it back on, I also changed the thermostat and temperature sending unit for the heat gauge as it seemed to be running cold." John, It seems as if you are contradicting yourself. You say it was "running cold" so you changed the temp sending unit. Why did you do that before properly diagnosing if it was the gauge or the sending unit? A gauge is $25.99 and an Infrared Thermometer is about $50.00 at NAPA. You need to properly diagnose and without knowing your actual engine operating temperature you have no idea what's going on. To say the gauge is working correctly is a bold statement when you truly don't know. My guess is that your thermostat, for that engine, is a 180 degree or 160 so if your gauge was reading low as in "This seemed to fix this problem and the engine ran at about 165 degrees." it could still be the culprit because if your t-stat is a 180 degree that's what your gauge should read and if it's a 160 it should read closer to 160 not 165.... Buy the Infrared and trouble shoot it... How's your intake? Have you cleaned the basket and made sure the hose is not clogged with weeds before the strainer? How's your impeller?
"Second, I haven't had problems with the gauge up until now, so my question is why should the gauge suddenly go bad now?" and... "I recently removed and cleaned my heat exchange unit (on a Universal M35 B). After putting it back on, I also changed the thermostat and temperature sending unit for the heat gauge as it seemed to be running cold." John, It seems as if you are contradicting yourself. You say it was "running cold" so you changed the temp sending unit. Why did you do that before properly diagnosing if it was the gauge or the sending unit? A gauge is $25.99 and an Infrared Thermometer is about $50.00 at NAPA. You need to properly diagnose and without knowing your actual engine operating temperature you have no idea what's going on. To say the gauge is working correctly is a bold statement when you truly don't know. My guess is that your thermostat, for that engine, is a 180 degree or 160 so if your gauge was reading low as in "This seemed to fix this problem and the engine ran at about 165 degrees." it could still be the culprit because if your t-stat is a 180 degree that's what your gauge should read and if it's a 160 it should read closer to 160 not 165.... Buy the Infrared and trouble shoot it... How's your intake? Have you cleaned the basket and made sure the hose is not clogged with weeds before the strainer? How's your impeller?
John..
"Second, I haven't had problems with the gauge up until now, so my question is why should the gauge suddenly go bad now?" and... "I recently removed and cleaned my heat exchange unit (on a Universal M35 B). After putting it back on, I also changed the thermostat and temperature sending unit for the heat gauge as it seemed to be running cold." John, It seems as if you are contradicting yourself. You say it was "running cold" so you changed the temp sending unit. Why did you do that before properly diagnosing if it was the gauge or the sending unit? A gauge is $25.99 and an Infrared Thermometer is about $50.00 at NAPA. You need to properly diagnose and without knowing your actual engine operating temperature you have no idea what's going on. To say the gauge is working correctly is a bold statement when you truly don't know. My guess is that your thermostat, for that engine, is a 180 degree or 160 so if your gauge was reading low as in "This seemed to fix this problem and the engine ran at about 165 degrees." it could still be the culprit because if your t-stat is a 180 degree that's what your gauge should read and if it's a 160 it should read closer to 160 not 165.... Buy the Infrared and trouble shoot it... How's your intake? Have you cleaned the basket and made sure the hose is not clogged with weeds before the strainer? How's your impeller?
"Second, I haven't had problems with the gauge up until now, so my question is why should the gauge suddenly go bad now?" and... "I recently removed and cleaned my heat exchange unit (on a Universal M35 B). After putting it back on, I also changed the thermostat and temperature sending unit for the heat gauge as it seemed to be running cold." John, It seems as if you are contradicting yourself. You say it was "running cold" so you changed the temp sending unit. Why did you do that before properly diagnosing if it was the gauge or the sending unit? A gauge is $25.99 and an Infrared Thermometer is about $50.00 at NAPA. You need to properly diagnose and without knowing your actual engine operating temperature you have no idea what's going on. To say the gauge is working correctly is a bold statement when you truly don't know. My guess is that your thermostat, for that engine, is a 180 degree or 160 so if your gauge was reading low as in "This seemed to fix this problem and the engine ran at about 165 degrees." it could still be the culprit because if your t-stat is a 180 degree that's what your gauge should read and if it's a 160 it should read closer to 160 not 165.... Buy the Infrared and trouble shoot it... How's your intake? Have you cleaned the basket and made sure the hose is not clogged with weeds before the strainer? How's your impeller?
True, but...
Mainsail is right: I was not sure if it was running cold or that was just what the gauge indicated. I just made the assumption that it was the thermostat or the sending unit. One thing I'm wondering: Is the sending unit for the gauge supposed to have pipe dope on the threads, or does this prevent proper grounding of this unit? If that is the case, then maybe that's the problem. When I installed the new sending unit, I put pipe dope on the threads. If it's not grounded properly, would this mean that the gauge would indicate it's running cooler than it actually is? If that's so, then maybe this is combined with failure to properly bleed the air out of the cooling system, which is causing the overheating in the first place. What does this theory sound like? PS. My wife was looking over my shoulder at this thread and commented on how nice it is that everybody takes the time to pitch in with suggestions. I agree with her.
Mainsail is right: I was not sure if it was running cold or that was just what the gauge indicated. I just made the assumption that it was the thermostat or the sending unit. One thing I'm wondering: Is the sending unit for the gauge supposed to have pipe dope on the threads, or does this prevent proper grounding of this unit? If that is the case, then maybe that's the problem. When I installed the new sending unit, I put pipe dope on the threads. If it's not grounded properly, would this mean that the gauge would indicate it's running cooler than it actually is? If that's so, then maybe this is combined with failure to properly bleed the air out of the cooling system, which is causing the overheating in the first place. What does this theory sound like? PS. My wife was looking over my shoulder at this thread and commented on how nice it is that everybody takes the time to pitch in with suggestions. I agree with her.
True, but...
Mainsail is right: I was not sure if it was running cold or that was just what the gauge indicated. I just made the assumption that it was the thermostat or the sending unit. One thing I'm wondering: Is the sending unit for the gauge supposed to have pipe dope on the threads, or does this prevent proper grounding of this unit? If that is the case, then maybe that's the problem. When I installed the new sending unit, I put pipe dope on the threads. If it's not grounded properly, would this mean that the gauge would indicate it's running cooler than it actually is? If that's so, then maybe this is combined with failure to properly bleed the air out of the cooling system, which is causing the overheating in the first place. What does this theory sound like? PS. My wife was looking over my shoulder at this thread and commented on how nice it is that everybody takes the time to pitch in with suggestions. I agree with her.
Mainsail is right: I was not sure if it was running cold or that was just what the gauge indicated. I just made the assumption that it was the thermostat or the sending unit. One thing I'm wondering: Is the sending unit for the gauge supposed to have pipe dope on the threads, or does this prevent proper grounding of this unit? If that is the case, then maybe that's the problem. When I installed the new sending unit, I put pipe dope on the threads. If it's not grounded properly, would this mean that the gauge would indicate it's running cooler than it actually is? If that's so, then maybe this is combined with failure to properly bleed the air out of the cooling system, which is causing the overheating in the first place. What does this theory sound like? PS. My wife was looking over my shoulder at this thread and commented on how nice it is that everybody takes the time to pitch in with suggestions. I agree with her.
John..
John no worries about the pipe dope as the water in the system, which the temp sending unit sticks into, acts as a ground too plus you'll still have plenty of metal to metal contact even with pipe dope or teflon tape but for future reference you don't need dope or teflon on a temp sending unit. I still say the best money you can spend is on an infrared thermometer. Heck you already spent that much just "replacing parts" that were most likely unnecessary. I have diagnosed many, many problems on my boat with my infrared from refrigeration problems to engine problems. I also shoot the water with it before blindly diving in so I know how much of a "shock" to expect. It also comes in handy in the spring when I need to paint my bottom. Sometimes the air temp is warm enough but my hull, especially the lead keel, is still too cold to apply the paint and by simply aiming my infrared thermometer at it I know in an instant if I can apply the paint or not... You should be able to find one for fairly short money at any of the auto-parts stores...
John no worries about the pipe dope as the water in the system, which the temp sending unit sticks into, acts as a ground too plus you'll still have plenty of metal to metal contact even with pipe dope or teflon tape but for future reference you don't need dope or teflon on a temp sending unit. I still say the best money you can spend is on an infrared thermometer. Heck you already spent that much just "replacing parts" that were most likely unnecessary. I have diagnosed many, many problems on my boat with my infrared from refrigeration problems to engine problems. I also shoot the water with it before blindly diving in so I know how much of a "shock" to expect. It also comes in handy in the spring when I need to paint my bottom. Sometimes the air temp is warm enough but my hull, especially the lead keel, is still too cold to apply the paint and by simply aiming my infrared thermometer at it I know in an instant if I can apply the paint or not... You should be able to find one for fairly short money at any of the auto-parts stores...
John..
John no worries about the pipe dope as the water in the system, which the temp sending unit sticks into, acts as a ground too plus you'll still have plenty of metal to metal contact even with pipe dope or teflon tape but for future reference you don't need dope or teflon on a temp sending unit. I still say the best money you can spend is on an infrared thermometer. Heck you already spent that much just "replacing parts" that were most likely unnecessary. I have diagnosed many, many problems on my boat with my infrared from refrigeration problems to engine problems. I also shoot the water with it before blindly diving in so I know how much of a "shock" to expect. It also comes in handy in the spring when I need to paint my bottom. Sometimes the air temp is warm enough but my hull, especially the lead keel, is still too cold to apply the paint and by simply aiming my infrared thermometer at it I know in an instant if I can apply the paint or not... You should be able to find one for fairly short money at any of the auto-parts stores...
John no worries about the pipe dope as the water in the system, which the temp sending unit sticks into, acts as a ground too plus you'll still have plenty of metal to metal contact even with pipe dope or teflon tape but for future reference you don't need dope or teflon on a temp sending unit. I still say the best money you can spend is on an infrared thermometer. Heck you already spent that much just "replacing parts" that were most likely unnecessary. I have diagnosed many, many problems on my boat with my infrared from refrigeration problems to engine problems. I also shoot the water with it before blindly diving in so I know how much of a "shock" to expect. It also comes in handy in the spring when I need to paint my bottom. Sometimes the air temp is warm enough but my hull, especially the lead keel, is still too cold to apply the paint and by simply aiming my infrared thermometer at it I know in an instant if I can apply the paint or not... You should be able to find one for fairly short money at any of the auto-parts stores...
Pipe Dope
The sending unit requires good ground to engine block, pipe dope / teflon tape should not be used. New idea! How is water flow at exhaust, any steam after running for an hour. How long since the mixing elbow has been cleaned. I had delayed alarm when I purchased Fullsailed in 2004. Steam and alarm after about 90 minutes @ 2500 rpm. Mixing elbow was culprit. Common issue on Yanmar 2GM20F Dennis W. S/V FullSailed
The sending unit requires good ground to engine block, pipe dope / teflon tape should not be used. New idea! How is water flow at exhaust, any steam after running for an hour. How long since the mixing elbow has been cleaned. I had delayed alarm when I purchased Fullsailed in 2004. Steam and alarm after about 90 minutes @ 2500 rpm. Mixing elbow was culprit. Common issue on Yanmar 2GM20F Dennis W. S/V FullSailed
Pipe Dope
The sending unit requires good ground to engine block, pipe dope / teflon tape should not be used. New idea! How is water flow at exhaust, any steam after running for an hour. How long since the mixing elbow has been cleaned. I had delayed alarm when I purchased Fullsailed in 2004. Steam and alarm after about 90 minutes @ 2500 rpm. Mixing elbow was culprit. Common issue on Yanmar 2GM20F Dennis W. S/V FullSailed
The sending unit requires good ground to engine block, pipe dope / teflon tape should not be used. New idea! How is water flow at exhaust, any steam after running for an hour. How long since the mixing elbow has been cleaned. I had delayed alarm when I purchased Fullsailed in 2004. Steam and alarm after about 90 minutes @ 2500 rpm. Mixing elbow was culprit. Common issue on Yanmar 2GM20F Dennis W. S/V FullSailed
I just put 4 turns of teflon pipe sealant tape on a 1/2
inch copper fitting and threaded it hand tight into a brass fitting and checked for continunity. There was zero ohms resistance. I don't believe that pipe dope cpild be considered an insulator between pipe fittings.
inch copper fitting and threaded it hand tight into a brass fitting and checked for continunity. There was zero ohms resistance. I don't believe that pipe dope cpild be considered an insulator between pipe fittings.
I just put 4 turns of teflon pipe sealant tape on a 1/2
inch copper fitting and threaded it hand tight into a brass fitting and checked for continunity. There was zero ohms resistance. I don't believe that pipe dope cpild be considered an insulator between pipe fittings.
inch copper fitting and threaded it hand tight into a brass fitting and checked for continunity. There was zero ohms resistance. I don't believe that pipe dope cpild be considered an insulator between pipe fittings.
mixing elbow
I have had the boat about 6 months. It's almost 10 years old and the engine has about 325 hours on it. I have not cleaned the mixing elbow and my guess is that the previous owner never did either. Would it need cleaning after this number of hours of use? Or is the hours of use less the issue than the age, since the salt water sits in there whether the motor is running or not? (Again, though, it seems to me that the problem most likely has something to do with the work I just did on the motor.)
I have had the boat about 6 months. It's almost 10 years old and the engine has about 325 hours on it. I have not cleaned the mixing elbow and my guess is that the previous owner never did either. Would it need cleaning after this number of hours of use? Or is the hours of use less the issue than the age, since the salt water sits in there whether the motor is running or not? (Again, though, it seems to me that the problem most likely has something to do with the work I just did on the motor.)
mixing elbow
I have had the boat about 6 months. It's almost 10 years old and the engine has about 325 hours on it. I have not cleaned the mixing elbow and my guess is that the previous owner never did either. Would it need cleaning after this number of hours of use? Or is the hours of use less the issue than the age, since the salt water sits in there whether the motor is running or not? (Again, though, it seems to me that the problem most likely has something to do with the work I just did on the motor.)
I have had the boat about 6 months. It's almost 10 years old and the engine has about 325 hours on it. I have not cleaned the mixing elbow and my guess is that the previous owner never did either. Would it need cleaning after this number of hours of use? Or is the hours of use less the issue than the age, since the salt water sits in there whether the motor is running or not? (Again, though, it seems to me that the problem most likely has something to do with the work I just did on the motor.)
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