View Full Version : Strength of coolant in 2015 Moomba mondo

09-27-2015, 08:06 PM
Winterized my boat this weekend. Before putting it away I thought I would check the strength of coolant. It tested at -20c I thought my tester was inaccurate so I used a different one. Same thing why would the dealer not have checked this. Temperature here in the winter will get as low as -35 at times. Just wondering if anyone else has experienced this?

09-28-2015, 11:52 AM
The dealer should be checking that and they should tell you what the reading is. An independent check would be worth the time as there are a few variables that change the protection and that is the initial mix that is used and also the dilution from water within the motor that is recirculated. Draining an engine of water isn't rocket science but using antifreeze can be. They should document what the freeze protection is and you should be able to verify.

09-28-2015, 12:18 PM
-35 is cold! Remember that anti-freeze/water mix greater than 65-70% actually raises the freezing point, so your mix could either be too low or too high (I've seen people winterize with 100% antifreeze thinking it is better than a 50/50 or 60/40 mix). Also, from a cooling standpoint water is better than antifreeze, I run 25/75 mix in my summer toys but I don't depend on that mix for freeze protection. At your temperatures, you may have to trade off running a high ratio for freeze protection or a lower mix for cooling but than expect to drain it for the winter. I'm glad I don't deal with temps that cold on a regular basis (a single overnight low of -20F is about the worst for me)

09-28-2015, 06:10 PM
All the RV/marine antifreeze I've seen is pre-mixed and -50

09-28-2015, 07:50 PM
They are talking about normal antifreeze (green) for closed cooled systems. The RV/Marine antifreeze doesn't go in the motor. Its 'bio' friendly and is intended to be used in RV water tanks, toilets, etc...

09-28-2015, 09:15 PM
They make RV/Marine antifreeze made for winterizing engines that is good for -50 and is pink and -100 that is purple. That is at what temp the antifreeze turns to slush.

09-28-2015, 10:35 PM
I have been using RV antifreeze for 15+ years to winterize my boat. I aware of what it is. HOWEVER, the OP has a 2015 Mondo which has the CLOSED COOLED Ford Raptor motor. That motor uses standard antifreeze similar to what you would find in your car (the green stuff). These engines don't require winterization (the heat exchanger does).

johndeereMoomba69 - did it test to -20C (celcius)? That's only -4F which does seem high. I'd check with the dealer. Since its closed cooled, did you just drain the heat exchanger to winterize? If so, I'd probably drain some coolant and top it off with pure antifreeze (no mix) and turn it over to mix it and retest. As long as you don't run it (pull the safety lanyard), it shouldn't fire and therefore heat up. You are just trying to circulate antifreeze to mix it.

09-29-2015, 05:53 PM
I think all of us are "missing the boat" on this one! The antifreeze being used in almost every new marine application (and even some construction equipment) is using the new environmentally friendly Polypropylene Glycol (PG) antifreeze. Not the Ethylene Glycol (EG) antifreeze we are all accustomed to using. That being said, the antifreeze tester you might be using is not one for PG rather EG. The specific gravity between the two are different and would produce a false reading. So you might have the correct low temp reading. I really can't see Skiers Choice sending a boat out, especially to the Great White North with the improper concentration.
Celsius, what's that? Here in Southern Florida it doesn't get below 40'F; I can't even fathom -20'F.