How to winter a Mercruiser

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macnorton

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Its a 1.7 tdi 120 hp with outdrive, boat is afloat and can't get muffs on the leg, will draining the intercooler
and heat-exchanger be enough? The block is full of antifreeze so its only the raw system that is of concern.
I know what the book said, but how do you do yours.
Thanks.
 
I had a pair of these engines in my old Sunline. I never drained the drives or filled with antifreeze, and the boat was either in freshwater or out on the hard. I kept tube heaters in the engine bay, with a thermal plug set to come on below 5c. Never had a problem even down to minus 19c.
 
rafiki_ said:
I had a pair of these engines in my old Sunline. I never drained the drives or filled with antifreeze, and the boat was either in freshwater or out on the hard. I kept tube heaters in the engine bay, with a thermal plug set to come on below 5c. Never had a problem even down to minus 19c.
Click to expand...

No mains where the boat is!
 
If you can reach the drive you can fit flush muffs with a short length of hose with a funnel in & pour antifreeze solution in whilst the engine is running until it comes out of the exhaust then switch off, you then have antifreeze in your raw water side which will prevent freezing & act as a corrosion inhibitor which is what kills many of those 1.7's
seen plenty of cracked blocks & heat exchangers due to frost despite what people say about "mine was fine"
 
Beamishken said:
If you can reach the drive you can fit flush muffs with a short length of hose with a funnel in & pour antifreeze solution in whilst the engine is running until it comes out of the exhaust then switch off, you then have antifreeze in your raw water side which will prevent freezing & act as a corrosion inhibitor which is what kills many of those 1.7's
seen plenty of cracked blocks & heat exchangers due to frost despite what people say about "mine was fine"
Click to expand...
Can't get to leg and don't have muffs, i intended to take of a pipe and pour antifreeze through but can't find any where?
Have drained manifold and intercooler but would prefer to be sure.
 
Beamishken said:
If you can reach the drive you can fit flush muffs with a short length of hose with a funnel in & pour antifreeze solution in whilst the engine is running until it comes out of the exhaust then switch off, you then have antifreeze in your raw water side which will prevent freezing & act as a corrosion inhibitor which is what kills many of those 1.7's
seen plenty of cracked blocks & heat exchangers due to frost despite what people say about "mine was fine"
Click to expand...
Can't get to leg and don't have muffs, i intended to take of a pipe and pour antifreeze through but can't find any where?
Have drained manifold and intercooler but would prefer to be sure.

Whoops double post!
 
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there is a hose comes in through the transom shield to the engine you could remove that one & block it off (to prevent water entering the boat) then fit a hose where you removed it from the engine & pour antifreeze in there.

you will need to get quite a long hose so you can get a 'head' so water can be forced round the engine as the circulation pump is in the leg
 
If it is in salt water I wouldn't expect the UK to get cold enough to freeze it and being full of water is better than being full of salty air. If its on fresh water then you could always buy a set of muffs as they're not expensive and borrow a dingy or tender from someone to access the leg from the water?
 
I think with this engines reputation for internal corrosion of the intercooler & heatexchanger at £2K a pop that the corrosion inhibiting property of the antifreeze is as important as the antifreeze property
The top & bottom covers of the intercooler are coated with what looks like a fired enamel but once the coating is breached they rot badly it's worth taking them off annually & checking them & treating them with epoxy or similar if the coating is damaged
The heatexchanger manifold also suffers but it's harder to service
 
Beamishken said:
there is a hose comes in through the transom shield to the engine you could remove that one & block it off (to prevent water entering the boat) then fit a hose where you removed it from the engine & pour antifreeze in there.

you will need to get quite a long hose so you can get a 'head' so water can be forced round the engine as the circulation pump is in the leg
Click to expand...

Thanks that is what I was looking for, could you say which side it is? Im not as flexible as I was!
boat is in fresh water.
 
Have you considered removing impeller and re-fitting cover, finding inlet pipe (do not know engine so can't comment), then find outlet pipe (should be connected to exhaust outlet. Again do not know engine so can't advise). Then get a 12 volt pump (bilge pump will work), a bucket, your winterisation fluid of choice and use the pump to pump fluid from bucket, into inlet pipe (with a suitable connection) around salt circuit then back into bucket via outlet pipe.

This will ensure circuit is completely protected. As mentioned corroded/ cracked heat exchanger / aftercooler would be a real PITA.
 
tribblehunter said:
Have you considered removing impeller and re-fitting cover, finding inlet pipe (do not know engine so can't comment), then find outlet pipe (should be connected to exhaust outlet. Again do not know engine so can't advise). Then get a 12 volt pump (bilge pump will work), a bucket, your winterisation fluid of choice and use the pump to pump fluid from bucket, into inlet pipe (with a suitable connection) around salt circuit then back into bucket via outlet pipe.

This will ensure circuit is completely protected. As mentioned corroded/ cracked heat exchanger / aftercooler would be a real PITA.
Click to expand...
It's an alpha drive therefore pump is in the leg!
 
macnorton said:
Actually thinking of removing impeller and fitting a belt driven Jabsco, but that is a job for the future need to protect it all now.
Click to expand...
That's probably a realy good idea,a front crank mounted pump from a volvo or a mercruiser bravo petrol engine would fit easily to the 1.7 diesel crank & you could fit a thru hull pick up scoop to help with the cooling water flow to the engine which is one of this engines problems
I might consider that for our rib which is fitted with a 1.7
 
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