85 Malibu Skier winterization

[WDK]

Hi guys...

 A friend just bought this boat with a 350 Mercruiser engine. We winterized it as per previous owners instructions:

1. Get up to temp on the lake. 170* F. Thermostat open

2. drain two block plugs and two manifold plugs and reinsert plugs  

3. Unhook raw water hose from through hull fitting 

4. Run engine (10-15 min after getting to 170* in 30*f ambient temps) while pouring antifreeze (total 3 gallons) through main water inlet hose until plenty of dark pink came out exhaust. 
 

my concern is the possible dilution of antifreeze by water that may have been in the hose between the impeller and engine. Is this cause for concern? We used -50* antifreeze and do get temps in the -40 range. 

thanks for any help in advance 

 

Edited October 25, 2020 by WDK

[WDK]

Also.... put boat on trailer obviously between running on lake and pulling hose at through hull fitting 

[SkiPablo]

you don't need to heat up the engine after you drain the block (unless I'm reading you wrong) - just run it long enough to add the antifreeze b/c you have already drained the water out of the block.  i typically run the -75 stuff, so if you are concerned it won't hurt to pull a few more gallons through

[oldjeep]

In addition to the 4 plugs you listed, pull off the j hose and blow out the heater if you have one.  Then just pour a couple of gallons in via the upper heater hose and the upper part of the j hose.

[WDK]

On 10/25/2020 at 9:28 PM, SkiPablo said:

you don't need to heat up the engine after you drain the block (unless I'm reading you wrong) - just run it long enough to add the antifreeze b/c you have already drained the water out of the block.  i typically run the -75 stuff, so if you are concerned it won't hurt to pull a few more gallons through

Thanks for the answer... my concern was that even though the block and manifolds were empty... we didn't drain the hose between the impeller and block. So as the antifreeze was added would have diluted somewhat as it fills the block and manifolds.