My boat has a 350 with a 288 penta leg....I think. I know it has a fresh water cooling system so does that mean I don't need to hook up water muffs when I run it? Have a small oil leak and need to leave it running for a bit to find it. I have never had a fresh water cooling system so I am a little unsure.
Fresh water cooling system
- Thread starter TGofers
- Start date
quicksilver11
Member
You need the muffs, there will be a raw water pump that will supply water to cool the FW cooling system.
It is pumping SW through the heat exchanger ect when in the water.
It is pumping SW through the heat exchanger ect when in the water.
bigbruce
Crew Member
The "fresh water cooling" isn't really "fresh" water. It's the same kind of water/anti freeze mixture that you have circulating in your car's engine block. It's purposes is to have this mixture circulating through the block rather than having raw sea water circulating there. The water/antifreeze mixture is circulated through a heat exchanger - that tubular thingy with hoses coming in and out of it - that uses raw sea water pumped up from your outdrive by a raw water pump to cool the mixture. As quicksilver sand, if your leg isn't in the water, you will need the muffs to ensure there is cold water pumped into the heat exchanger to cool the stuff circulating through the block.
wildthing
Well-Known Member
and if you are running a sea water pump
depending on its age change out or renew the impella in the sea pump as
well dont forget to flush the leg with muff's and the block via the raw intake
or you may find its cooled just by the leg
i have a sea pump on mine and installed a twist disconnect from the builders supply
bought two one go's inline before the pump the other i fitted a garden hose attachment
so rather than mess around with a toilet plunger under the boat i just lift the dog house and connect up the garden hose to flush with
could post a pic up if want
depending on its age change out or renew the impella in the sea pump as
well dont forget to flush the leg with muff's and the block via the raw intake
or you may find its cooled just by the leg
i have a sea pump on mine and installed a twist disconnect from the builders supply
bought two one go's inline before the pump the other i fitted a garden hose attachment
so rather than mess around with a toilet plunger under the boat i just lift the dog house and connect up the garden hose to flush with
could post a pic up if want
fillet_and_release
Member
Assuming a Volvo with a Johnson raw water pump, running it with out water will wipe out the pump impeller and over heat the rubber pieces between the manifolds and y pipe ( they will go first anyway. It's not nice to other things either.)
Muffs work well on my 280 leg. Not sure about yours but there is a drain hole on mine that I plug when I put the muffs on and it picks up water way quicker.
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Muffs work well on my 280 leg. Not sure about yours but there is a drain hole on mine that I plug when I put the muffs on and it picks up water way quicker.
Sent from my iPhone using Tapatalk
daddystoy
Well-Known Member
I am going to assume it is a 280 leg. I have a 270 leg which is virtually identical to a 280. Like other people have said, don't run your engine without muffs. You will burn out your impeller in the raw water pump do to overheating it by running the engine and not having water go through that pump to lubricate the impeller. Also as was mentioned there is an additional pick-up hole on the bottom of the leg. It is easy to find. It is about 1/2 to 3/4" in diameter. Plug this hole when using muffs. By plugging this hole when you are using muffs it allows the water to get into the cooling system much quicker and easier than if you don't plug it.
