View Full Version : Question on using FlushPro with Antifreeze

10-22-2009, 09:24 AM
My 07 Mobius LSV has the 325 Assault motor with the factory flushpro on it.

I bought 3 gallons of Marine/RV -50 degree antifreeze and was told that to get it to cycle through the engine that I pour this into a big pail, insert a small hose into the pail, and attach the other end of the hose into the flushpro.

I think this means that I turn on the engine and the motor and flushpro will such in the antifreeze and the existing water will flow out the back of the boat. Does that mean that once my 3 gallons are through the motor, block and all pipes will be filled with the antifreeze?

Any ideas would help. I am putting the boat into 'heated' storage but I want to be sure I get the water out - just in case.

Thanks everyone in advance.


you da man
10-22-2009, 09:34 AM
engine needs to be at operating temperature before the antifreeze is added or else it will not circulate through all parts of the engine.

10-22-2009, 09:38 AM
IU understand that. But when the 3 gallons go in, and water then flows through the engine and out the back, do I simply shut the motor off once all the antifreeze is sucked out of the bucket and starts coming out the back of the boat??

Does it really get 'everywhere'.

10-22-2009, 02:23 PM
Would like to know if I just have the antifreeze sucked up through the flushpro...and if 3 gallons is enough to know it will get all through the entire engine. Any one with insight, it would be much appreciated. Thanks

10-22-2009, 03:07 PM
Please see the post below. Looks like deerfield ran the engine on regular water til it reached operating tem and the thermostat opened. Then he switched to anti-freeze. But he recirculated the anti-freeze thru the system rather than running it once thru. Maybe deerfield can answer your question.

I always drain the water instead of running anti-freeze so I'm not much help on this one.


10-22-2009, 03:27 PM
Drain the block, disconnect and drain the exhaust manifold lines,drain the j tube, drain your impellar lines, reconnect
lines, reinstall block plugs, then run using flushpro. then check block plugs for the antifreeze. only way to be certain, or like others put a bucket under the exaust and circulate 5 gallons thru your motor after you drain the block, you still have to disconnect your exhust lines as there may still be water in those.

if you have a heater you have to drain this too before using flushpro

the above way is best way so as not to dilute your plumbing antifreeze with water in the block or heater

note never drain a hot engine then suck up anything cold even antifreeze into the block

not sure as to why you have a flush pro, do you use it in salt water

10-22-2009, 03:59 PM
here are the perko flushpro instructions, man i have way too much time on my hands lol

Directions for Winterizing Your Boat (Out of Water):
1. After flushing with fresh water, open all drain cocks.
2. When all water is drained out of the engine, close drain cocks and tape shut
the water inlet on the bottom of the boat.
3. Insert adapter into garden hose connection on the top of the valve.
4. Using a 5 gallon bucket, mix applicable amount of anti-freeze and water
(See anti-freeze directions for temperatures and appropriate amounts of
anti-freeze and water mixture).
5. Place end of hose into bucket of anti-freeze mixture.

6. Start engine,

Do not exceed 1100 RPM. Allow engine to draw all antifreeze

solution into engine. Immediately shut off engine to prevent loss of
anti-freeze from exhaust.
7. Remove tape from intake and garden hose from valve.
Directions for Winterizing Your Boat (In Slip):
1. After flushing process is complete, remove adapter from FlushPro™ cap
strap and insert adapter into FlushPro™ valve.
2. Using a piece of garden hose, place male end of hose into FlushPro™
valve and place the other end into applicable amount of bio-degradable
anti-freeze mixture bucket, container etc. (approximately 5 to 10 gallons).
3. Open all pet cocks and drain engine block and water cooled headers. If pet
cocks are plugged, use a small nail to unclog openings. When all the water
has drained out, close all pet cocks and replace any plugs you have
4. Start engine(s) and your sea water pump will automatically pump antifreeze
from the bucket into your engine and headers.

Do not exceed 1100


When the bucket is empty Immediately shut down engine(s).You are
now winterized.

Are you confused now?

I usually drain mine like Al , much easier. Occasionally i will pump antifreeze into the block thru a block plug after i have drained it. My thoughts are this may reduce corrosion thru the winter, but most of the corrosion probably occurs during the summer. Also , by draining you will get out any corrosion particles that have built up in the bottom of the block.

10-22-2009, 04:46 PM
Your wrote 1. After flushing with fresh water, open all drain cocks.

What is a drain cock? No jokes please!

10-22-2009, 04:52 PM
those are the perko instructions not mine.......but the drain cocks are the block drain plugs located on either side of the lower block

10-22-2009, 08:45 PM
You can warm the motor and then add antifreeze via the flush pro and then drain the engine etc afterwards and leave the waterjackets virtually empty with the left over being antifreeze in the block. Esentially thats the way i do it. Kinda the best of both worlds.If you have a heater leave that full of antifreeze or blow the lines out there as well.

10-23-2009, 11:01 AM
Whats a waterjacket?

10-23-2009, 11:55 AM
Passages in the engine block thru which the water circulates.