Author |
Message |
Bob Kelly
New member Username: bkseawolf
Post Number: 1 Registered: 08-2011
| Posted on Tuesday, August 16, 2011 - 12:23 am: |
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Hello all, I have a P-60 in my 1962 Columbia 29. When I bought it 12 years back, it did not have a t-stat. Just a gate valve to adjust the raw water circulation. When I installed a DOYLE t-stat, I noticed two things. One, I would get no raw water to the exhaust until the t-stat reached temp. I thought there should be water at the exhaust at all times? Two, a lot of steam coming out of exhaust, even though temp gauge showed normal operating temp, 160 degrees I believe. I also mounted the t-stat on the engine bulkhead due to room limitations and the salt water that sat in it corroded the internal parts. Any advise regarding this cooling system would be helpful. I have been running without a t-stat for over a couple of years now. Thanks. Bob |
Howard Taylor
Member Username: catec
Post Number: 14 Registered: 01-2006
| Posted on Tuesday, August 16, 2011 - 09:45 am: |
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Hi Mr. Kelly, 160 degrees is too hot for salt water cooling. and a thermostat tends to restrict the water flow from the water cooled exhaust causing overheating of the exaust system and associated hoses. I prefer using a small ball valve to control cooling flow to the engine and manually adjust for 110 to 120 degrees. [email protected] |
Eddie Ross
Senior Member Username: eddie
Post Number: 269 Registered: 04-2003
| Posted on Tuesday, August 16, 2011 - 10:00 am: |
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It doesn't sound like you have the proper hose routing. Thermostat housing should be attached to the exaust manifold with a 1/2" pipe thead fitting. There are then 2 hoses, one from the water inlet and one from the cylinder head, on either end of the thermostat housing. |
Eddie Ross
Senior Member Username: eddie
Post Number: 270 Registered: 04-2003
| Posted on Tuesday, August 16, 2011 - 11:26 am: |
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Ben Sidaway
New member Username: b_sidaway
Post Number: 1 Registered: 08-2011
| Posted on Tuesday, August 16, 2011 - 09:40 pm: |
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I have the thermostat in the same position as in the photo above. I also don't get any water in the exhaust until the thermostat opens at 160. Then I get steam and water periodically from the exhaust as the thermostat open and closes. The engine has run fine like this for years. I got a new thermostat from Moyer Marine where they state that the thermostat is designed to open at 160 deg. For freshwater the temperature will settle between 170-190 |
Bob Kelly
New member Username: bkseawolf
Post Number: 2 Registered: 08-2011
| Posted on Thursday, August 18, 2011 - 12:01 am: |
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Thanks to all for your suggestions. I had routed all hoses in accordance to the Palmer manual. The reason the t-stat in not on the manifold is that my companion way step sets on top of this location and would not fit, so I installed a hose from the manifold location of the original t-stat placement to the t-stat that I mounted on the engine compartment bulkhead. The way the manual says to install the t-stat, I can see no way to have water out the exhaust until the t-stat opens at temp; as in Ben's reply. I did drill a small hole in the t-stat plate to allow a trickle of water to hit the exhaust before the t-stat opens. The steam out the exhaust bothered me so I pulled out the t-stat all together and have been running the engine without one. I may simplify as Howard suggest, and just install a ball valve in place of the t-stat. Any ideas on why I am getting steam out the exhaust while running with a t-stat??. |
Eddie Ross
Senior Member Username: eddie
Post Number: 271 Registered: 04-2003
| Posted on Thursday, August 18, 2011 - 09:46 am: |
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The thermostat housing diverts water rather than stopping the flow as with automotive engine. Note that the cold water hose is not seen in the photograph. The thermostat within the housing shuts off the water coming from the engine allowing cold water to enter directly from the seacock. When it opens it allows hot water from the engine through and shuts off the cold water intake. |
Bob Kelly
New member Username: bkseawolf
Post Number: 3 Registered: 08-2011
| Posted on Thursday, August 18, 2011 - 10:49 pm: |
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Eddie, The t-stat has one end stamped "bypass" and the other stamped "out". I have the out line plumbed to my lift canister that is connected to the exhaust, and goes overboard. The bypass side is plumbed to the bypass tee that is just beyond the inlet seacock. As I see it, the water pump flows water from the seacock to the engine block and up to the t-stat and through the bypass back to the inlet to circulate again until the t-stat reaches its opening temp, 160 for this t-stat, and the cooling water is diverted to the exhaust and overboard. That is why I am getting no water in the exhaust until the t-stat opens. This seems strange to me as I thought other raw water cooled engines had water out the exhaust as long as the engine was running. I may be mistaken. Please let me know if my thoughts above are correct on the way the system works. Any ideas on the steam that comes out with the exhaust when the t-stat opens? Thanks. Bob |
Eddie Ross
Senior Member Username: eddie
Post Number: 272 Registered: 04-2003
| Posted on Thursday, August 18, 2011 - 11:11 pm: |
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That doesn't sound right. E-mail me at [email protected] I have some skematics. Note that the photo does not show the bypass water hose which is off the picture beyond the left hand side of photo. |
Ben Sidaway
New member Username: b_sidaway
Post Number: 2 Registered: 08-2011
| Posted on Tuesday, August 23, 2011 - 10:06 pm: |
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Bob, check out an old post of mine showing how my thermostat is plumbed. I think it is the same as Eddie's. Post is at http://www.oldmarineengine.com/discus/messages/3430/6234.html |