Winterization

Spidrmunky

Cadet
Joined
Aug 2, 2020
Messages
23
Hey everyone. Is it okay to drain the block, put the drain cocks back in, fire up boat while running antifreeze thru the intake? Is this harmful at all?
 

Spidrmunky

Cadet
Joined
Aug 2, 2020
Messages
23
I’m just worried about no liquid in the boat for the time it takes to circulate and come out exhaust
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,487
or follow the manual. drain all the plugs, prod and poke the drains, and if you want to add antifreeze, use a funnel and add to the thermostat housing
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,158
Trying to suck it up can burn the impeller. I manually (remove the drain plugs) drain, poke the holes, and disconnect the bottom end of the big hose that connects the thermostat housing to the circulation pump. Them put some gasket sealer on the threads and reinstall the plugs. Then reconnect the bottom end of the big hose and disconnect the top end. Stick a funnel in the big hose and fill with AF till it spurts out of the thermostat housing. Reconnect hose and the engine is done very easy. Do the exhaust manifolds the same way. Manual drain & backfill.
 

muc

"Retired" Association of Marine Technicians...
Joined
Jul 7, 2004
Messages
2,170
Hey everyone. Is it okay to drain the block, put the drain cocks back in, fire up boat while running antifreeze thru the intake? Is this harmful at all?

That's how thousands of boats are done every year in Minnesota for about the last 25 years.
Some will use a bilge pump or water puppy and most use gravity to supply the muffs.

Just don't use the cheap pink stuff from the big box stores that has Alcohol in it.

Note that in the new engines antifreeze isn't recommended anymore. It's now required!
 

Spidrmunky

Cadet
Joined
Aug 2, 2020
Messages
23
I thought it would be okay. I also watched a mercury video on YouTube that drained then ran coolant through muffs after draining. Anyway, I appreciate everyone’s input.
 

RaceCarRich

Petty Officer 1st Class
Joined
May 31, 2015
Messages
234
Spider, if you are really concerned about starting after draining (although I’m sure the advice you already received here is good) this guy’s kit has it running on water with ability to switch from water to antifreeze while the boat is running so never runs dry. He pulls all plugs afterwards to confirm what comes out is pink.

Myself (5.0, MPI) I’m trying to decide between feeding antifreeze through the muffs -or- simply draining then filling each hose going to thermostat housing with antifreeze. I’m open to opinions as to which is better.

Not trying to hijack but in about a month we’ll be seeing a lot of winterizing threads!
 

starcentral

Seaman Apprentice
Joined
Sep 27, 2018
Messages
39
The dumbest thing I ever saw was a guy on YouTube fill a kiddie pool with dozens of jugs of antifreeze and dunk his drive in it.

On my 3.0L I use drain hoses then fill up through large hose on water pump, fast easy and painless.
 
Top