G
Guest
Guest
I have a direct cooled Perkins 4107 and wonder how users add antifreeze to protect from frost.
vyv_cox
Well-known member
I have always drained everything down and left it empty. This includes the exhaust water trap and calorifier. There is normally a drain tap or screw at the lowest point on the block (can't speak for your engine). However, I do think that this leaves the internal cooling spaces liable to corrosion over the winter.
Coating the internal surfaces with antifreeze seems like a good idea to inhibit corrosion, but the method often advocated leaves a lot to be desired. This is to fill a bucket with antifreeze solution and run it through on a total loss basis. A far better idea, which I have used once, is to take a 5 gallon plastic drum, cut one side or a large slot out of it and hang it over the transom so that the exhaust fitting discharges into it. Then take a hose from it to the engine water pump suction. Half fill the drum with antifreeze solution and run the engine. Exhaust gases are discharged harmlessly but the coolant is recirculated. Run until the coolant gets up to normal running temperature, by which time all internal surfaces are well coated. There is then no need to drain down.
Coating the internal surfaces with antifreeze seems like a good idea to inhibit corrosion, but the method often advocated leaves a lot to be desired. This is to fill a bucket with antifreeze solution and run it through on a total loss basis. A far better idea, which I have used once, is to take a 5 gallon plastic drum, cut one side or a large slot out of it and hang it over the transom so that the exhaust fitting discharges into it. Then take a hose from it to the engine water pump suction. Half fill the drum with antifreeze solution and run the engine. Exhaust gases are discharged harmlessly but the coolant is recirculated. Run until the coolant gets up to normal running temperature, by which time all internal surfaces are well coated. There is then no need to drain down.
G
Guest
Guest
Agree with Vyv in that draining down is the simpler of the two methods. We used to connect up a freshwater supply to the engine once the boat had been hauled out and run the engine until it was warmed up. We then drained down the block and the exhaust manifold. Also need to make sure that water in not lying in any low point of the engine and you need to check any heat exchangers on the engine or gearbox.
regards
John C
regards
John C
mike_kolling
N/A
Run engine up until its hot, then switch it off.
Close the seacock, open the lid of the water filter and start the engine up and tip Antifreeze into the water filter until it comes out of the exhaust. Its a bit of a two man job but works well.
Close the seacock, open the lid of the water filter and start the engine up and tip Antifreeze into the water filter until it comes out of the exhaust. Its a bit of a two man job but works well.
AndrewB
Well-known member
Never bothered.
Just drain off. (a) Its seawater, so its going to take a pretty cold spell to freeze it, specially inside a boat; (b) As long as there is plenty of space for expansion, some freezing probably won't cause any harm.
A bit casual perhaps, but I had a direct-cooled engine for 20 years and never had problems even in 1986 when the boat was covered by a snowdrift for three weeks, and the creek froze over.
Just drain off. (a) Its seawater, so its going to take a pretty cold spell to freeze it, specially inside a boat; (b) As long as there is plenty of space for expansion, some freezing probably won't cause any harm.
A bit casual perhaps, but I had a direct-cooled engine for 20 years and never had problems even in 1986 when the boat was covered by a snowdrift for three weeks, and the creek froze over.
angusmacgregor
New member
It's fairly easy. Hot or cold, remove cover to thermostat and lift out thermostat. Drain block and close tap. Pour diluted antifreeze solution into thermostat housing, about 2litres of 50% solution. Replace thermostat and cover. N.B. It is all lost as soon as the engine is resarted and runs up to temperature.