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Unable to Circulate anti freeze into engine Please HELP!

2K views 8 replies 7 participants last post by  Rockter 
#1 ·
I have a model 5411 Universal Diesel. It says that it is raw water cooled. It has two rubber hoses coming out of the thru-hull near the engine. One hose goes to the oberderfor water pump on the left side of the engine The 2nd hose goes to the right side of the engine which looks like its going to the exhaust.

I disconnected both hoses put it in a bucket of antifreeze. I ran the engine for about ten min. it approached 130 degrees F its normal operating temp is 150F. What was happening is it seemed to be circulating the anti freeze up the first hose through the pump and out the 2nd hose. I was expecting it to pump out the stern exhaust thru hull. But my friend who was looking back there saw nothing come out of there. What am I doing wrong, first time winterizing this engine.

Does the engine need to be 150 degrees to pump out the stern of the boat? Why does it recirculate the water through the 2nd hose, I thought raw water cooled would just run the raw water in through the pump through the engine and out the stern? Please help, thanks.:confused:
 
#3 ·
the 5411 is an 11 hp engine as I recall - used to have one years ago.
Can't understand how (or why) you could have 2 intake hoses -the only one of any import is the one going into the oberderfor pump - put that one in the antifreeze after the thermostat reaches op temp at which point the thermostat opens allowing the pump to suck through to the exhaust.
 
#8 · (Edited)
I have a model 5411 Universal Diesel. It says that it is raw water cooled. It has two rubber hoses coming out of the thru-hull near the engine. One hose goes to the oberderfor water pump on the left side of the engine The 2nd hose goes to the right side of the engine which looks like its going to the exhaust.
This is the Model 5411 Operation Manual . Save it for future reference if you don't have a copy. Page 36 shows your cooling system. The second hose is the recirculating hose.

I disconnected both hoses put it in a bucket of antifreeze. I ran the engine for about ten min. it approached 130 degrees F its normal operating temp is 150F. What was happening is it seemed to be circulating the anti freeze up the first hose through the pump and out the 2nd hose. I was expecting it to pump out the stern exhaust thru hull. But my friend who was looking back there saw nothing come out of there. What am I doing wrong, first time winterizing this engine.

Does the engine need to be 150 degrees to pump out the stern of the boat?
No, there should be a small flow out the exhaust even when the thermostat is closed. Perhaps you have some scale build up in the system that is preventing overboard discharge when the thermostat is closed.

Why does it recirculate the water through the 2nd hose, I thought raw water cooled would just run the raw water in through the pump through the engine and out the stern? Please help, thanks.:confused:
Hopefully you'll understand the explanation in the manual on how the cooling system works. If you remove the thermostat and pinch off the recirculating hose with vise grips, antifreeze should be forced out the exhaust. When removing the thermostat you may see the restriction that is blocking flow to the exhaust and be able to clean it out. If not, it is probably a good idea to flush the engine with a mild acid to clean out deposits. There are other threads in Sailnet that describe how to do this. After you have antifreeze coming out the exhaust, shut off the engine and replace the thermostat and hoses. Make sure you don't put the thermostat in backwards. See page 39 of the Parts Manual (You should save a copy of this too. It's $30.25 at Torreson Marine)

Not to hijack, but does anyone have a copy of the Service / Shop manual?
 
#9 ·
Sau...

There should be a way of draining the block(s). On the olde Volvo MD17c I have... three separate barrels... there are three wee drain plugs at the bottom of the blocks.
Often, for winter, I just drain the system and leave it dry, blowing the water out of the gearbox cooling channel just by blowing on the hose.
If it's dry, it cannot freeze.
I cracked the aftmost block 2 winters ago when I let it freeze, in an unexpected -14C Scottish night. It still weeps slightly, and weeps out, thankfully.
 
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