Major Generator Problems (Formerly Pink vs. Green Coolant for Kohler Genset?)

[Dockhead]

My 1500 RPM Kohler genset is the one major piece of gear on board which has never given me a minute of trouble -- it has been totally bulletproof in 3 years and 310 hours of service. I don't even know that much about it -- other than changing oil and fuel and oil filters, I've never touched it. Never even had the sound enclosure off of it.

Until yesterday. I ran it the other day for 13 hours putting a good charge on my flattened batteries. The next morning, I started it, and in 10 minutes it shut down. My heart sank. Oh no . . . . . that's all I need now, I thought.

Started it up, and it shut down again. There was no coolant in the overflow bottle. I let it cool off, took off the top panel of the sound enclosure (for the very first time), filled the cooling system. It took a couple of liters. So it overheated and was automatically shut down. Oh crap . . .

But it turned out not to be so bad. Following the ancient mechanic's principle of eliminating the simple things first, I checked the seawater strainer -- bingo! A big piece of seaweed totally clogging it. I took it out and thoroughly washed the strainer. After that, the genset ran fine.

But I noticed that the coolant is opaque, brown, and sludgy, which cannot be good. I can only guess that someone -- I guess the engineer who did total service of engine and genset when I bought the boat -- mixed pink coolant with the green stuff. Oh crap again . . .

I hope it hasn't caused any permanent damage. The Kohler manual doesn't say what type to use. I'll call them tomorrow, but I guess the first thing I will do is thoroughly flush out the system. Fill it with plain water, run it, let it cool off, drain it completely, repeat several times. And just run it on plain water for a while if I need to, until I can get some info from Kohler.

Anybody had this problem?

[ShaunJ]

I have seen that opaque, brown, and sludgy looking stuff in cars that haven't had any service to the cooling system after years of neglect the green stuff turns pretty foul looking.
Are you sure someone did service it?

[barnakiel]

The sludgy thing may be rust deposits. Flush the thing real well. Replace zincs. If the exchanger is easy to take off, take it off, open, clean. Check out the pump/s at the same time.

The colors of the coolant may be the colors the mixing company gave them - different colors for different content of glyco.

We use less glyco in hot climes, more in cold. Plenty for winter lay-up.

Cheers,
b.

[bstreep]

As noted above, I'd give it a complete flush.

The coolant types are specific to the engines. If you have an iron block with an iron head, plain old green coolant is fine. One of the other premium coolants is specifically for engines with a mixed environment - aluminum head and iron block, for instance. Since we drive MB vehicles, I only use MB coolant in our cars... and in our boat. What the heck, it's $18 a gallon. Who cares.

Additional thought: Water is the best for heat transfer. 50% MAX ratio of antifreeze vs. water. If you use 100% antifreeze, you may very well have an overheating problem!

[thinwater]

"The sludgy thing may be rust deposits. Flush the thing real well. Replace zincs. If the exchanger is easy to take off, take it off, open, clean. Check out the pump/s at the same time."
True. Air leaks are also VERY important and can make ANY coolant turn rusty.

"The colors of the coolant may be the colors the mixing company gave them - different colors for different content of glyco."
Nonsense. Variable colors are only found in winterizing PG products, which should NEVER be used in engines cooled by glocol mixtures in service. Apropriate vehical engine coolant should be used, either automotive or diesel type in wet sleave engines only. It does not need to be a non-toxic type and probably should not be (no trucks are). BTW, neither EG nor PG are toxic to fish in ralistic dilutions, though recycling is always best.

"We use less glyco in hot climes, more in cold."
Nonsense in the case of a glycol-cooled engine. Regardless of the climate, all manufactures require a 50/50 mixture to insure sufficient corrosion protection and overheat protection. The corrosion protection is the thing.









Plenty for winter lay-up.

Cheers,
b.[/QUOTE]

[bstreep]

Originally Posted by thinwater

"The colors of the coolant may be the colors the mixing company gave them - different colors for different content of glyco."
Nonsense. Variable colors are only found in winterizing PG products, which should NEVER be used in engines cooled by glocol mixtures in service. Apropriate vehical engine coolant should be used, either automotive or diesel type in wet sleave engines only. It does not need to be a non-toxic type and probably should not be (no trucks are). BTW, neither EG nor PG are toxic to fish in ralistic dilutions, though recycling is always best.

"We use less glyco in hot climes, more in cold."
Nonsense in the case of a glycol-cooled engine. Regardless of the climate, all manufactures require a 50/50 mixture to insure sufficient corrosion protection and overheat protection. The corrosion protection is the thing.
.

[/QUOTE]

Sorry, but I disagree with both of your "nonsense" comments:

1) Coolant is often colored by the "brand" for their use: for instance, Mercedes Benz, BMW, and VW/Audi/Porsche all use the SAME coolant, but all are colored for their specific brands, and NONE of them resemble "green" generic EG. All of the above are formulated for a mixed alloy system, rather than a pure iron system, as "green" coolant is.

2) Again incorrect. In warm weather, a lower ratio of "coolant" to water will result in better heat exchange. EG/PG are much poorer heat exchangers than water. You want to use enough "coolant" to keep corrosion and bubble formation (that erodes metal as they collapse) at bay, but still provide optimum heat transfer. 100% water is a much better "coolant" than EG/PG. In areas of very low temperatures, 50/50 may not be enough. All of this in mind, my experience has been that too many people think "more is better" when it comes to "coolant", when the opposite is often true.

[Capn Morgan]

Hi Dockhead

Flush it yes, but my suggestion would be not to leave the water inside for any length of time. Minerals in it will cause deposits rather quickly as well as corrosion. If you can't find pre-mixed coolants, you can always mix your own, but if so, try to add de-mineralized water. If you have a watermaker, you may be able to feed it with fresh water from your tanks. The product will be nearly as good as distilled water and good enough for the engine or genset.

Cheers!

M

[Capn Morgan]

I forgot to mention that most engine manufacturers recommend changing the coolant every couple of years... and not to mix them.

[Dockhead]

Oh, crap - digging through the manual I see that this genset has an anode in the cooling system. I have not changed it in my ownership. My main engine doesn't have one and I just didn't think about it. I wonder if I have major corrosion damage? All that carp in the cooling system might just be rust

[leftbrainstuff]

+1 for bstreep. Colour is no indicator of coolant ingredients or concentration. Minimum temperature is the primary parameter in determining what mix ratio to use. Also take note of the other poster who mentioned cast iron and aluminum combinations. I have a preference for using neat coolants and making my own mix.

[mrm]

Well, as for colours it can get complicated. 'Branding' same product with colour happens. But colour is also used to distinguish incompatible chemistries of additives packages used. A good example is Volkswagen. Their original coolant G11 was greenish (concentrate looking greenish-blueish). Later they introduced pink coloured G12 which was *not* compatible with G11 and resulted in brown sludge when the two were mixed. Even later they introduced purple (a G12A?, iirc) formulation which (again iirc) *was* backwards compatible.... So there is no one good answer here.

As for OP problem, flush it with clean water, fill with distilled or deionized for the time being and replace with the correct type when you get that information.

[bstreep]

The anode should be for the SW part of the cooling system, right?

This does remind me that I'm due for a flush for both the engine and the generator.

[Cheechako]

Often the pink is the animal safe stuff and the green ethylene glycol. Which color compliments your gen housing well?

[Hud3]

I'm confused. I've used the pink antifreeze (propylene glycol based) to winterize my boat's potable water system because it's non-toxic, but I didn't think it was made for use in an engine cooling system. Am I wrong?

My Yanmar (2001 4JH3(B)E) came charged with the orange coolant (ethylene glycol based). You're not supposed to mix the green with the orange, although the Texaco orange can tolerate up to 10% of the green.

[Cheechako]

AfAIK the pink is for engines, just animal safe and more expensive... from Wiki:
"Propylene glycol is a component in newer automotive antifreezes and de-icers used at airports. Like ethylene glycol, the freezing point of water is depressed when mixed with propylene glycol due to increased opportunity for hydrogen bonding. Unlike ethylene glycol, propylene glycol is of very low toxicity. Both are readily biodegradable."
Also interesting, going from 50% mix to 60% AF mix takes you from -28F protection to -60F protection! (for those of you considering the NW passage!)