Coolant Information
Which coolant?
According to Richard Mastry, with Mastry Engines, Catalina's supplier of all Yanmar engines:
The engines use Yanmar Ultralife YG30.
The recommended alternatives are all pre-mixed:
Texaco LLC part #7998
Havoline LLC part #7994
These are also listed in the Engine manual. Although he did not explicitly say that you should flush out the Yanmar coolant to use the other approved brands, he recommended it. I believe the other two brands are also red in color. Interestingly enough, here in the Northeast it has been equally difficult for me to find either the Texaco or Havoline brands.
Finally, I buy all of my Yanmar spares from Old Port Marine in Newport RI. I greatly respect their advice and expertise and asked what they used. For their launches, rebuilds and repowers they use Shell Rotella TELC Red 50/50. I will probably go with this if and when I can no longer get access to the Yanmar stuff (which is surely rebranded from someone else)....
Amazing that something as simple as which coolant to use can be so
complicated! ~ Jon Vez
When asked about flushing the coolant, Jon explained:
As for flushing, yes using distilled water until you can get 90% of the old out, then refill with what you are going to use, drain and refill should do it (a royal pain, which is why I did all the research before in the first place). You will find that the hardest part is getting the old stuff out of the hoses leading to the hot water heater. You can disconnect those hoses at the heater and try to drain as much as you can from there. Finally you will probably have the airlock problem rearing its ugly head again. For this, just keep filling and vacating air bubbles. Some folks crack the hose at the water heater and try to burp out the air. I find that the low coolant drain is ideally situated to get most of the air out with relative ease...good luck and I've confused you in any of this, let me know and I will try to clarify...
According to Richard Mastry, with Mastry Engines, Catalina's supplier of all Yanmar engines:
The engines use Yanmar Ultralife YG30.
The recommended alternatives are all pre-mixed:
Texaco LLC part #7998
Havoline LLC part #7994
These are also listed in the Engine manual. Although he did not explicitly say that you should flush out the Yanmar coolant to use the other approved brands, he recommended it. I believe the other two brands are also red in color. Interestingly enough, here in the Northeast it has been equally difficult for me to find either the Texaco or Havoline brands.
Finally, I buy all of my Yanmar spares from Old Port Marine in Newport RI. I greatly respect their advice and expertise and asked what they used. For their launches, rebuilds and repowers they use Shell Rotella TELC Red 50/50. I will probably go with this if and when I can no longer get access to the Yanmar stuff (which is surely rebranded from someone else)....
Amazing that something as simple as which coolant to use can be so
complicated! ~ Jon Vez
When asked about flushing the coolant, Jon explained:
As for flushing, yes using distilled water until you can get 90% of the old out, then refill with what you are going to use, drain and refill should do it (a royal pain, which is why I did all the research before in the first place). You will find that the hardest part is getting the old stuff out of the hoses leading to the hot water heater. You can disconnect those hoses at the heater and try to drain as much as you can from there. Finally you will probably have the airlock problem rearing its ugly head again. For this, just keep filling and vacating air bubbles. Some folks crack the hose at the water heater and try to burp out the air. I find that the low coolant drain is ideally situated to get most of the air out with relative ease...good luck and I've confused you in any of this, let me know and I will try to clarify...
Ron Ginter added: Okay, this may be getting over the top, but for anyone interested, I found this on the Cruisers Forum:
From “Keeping It Cool” ~ by Paul Weissler“ http://silverstone.fortunecity.com/ferrari/464/coolant.htm
Conventional American coolant (green or gold) contains silicates (a long-used aluminum corrosion inhibitor) and other inhibitors. Silicates work quickly to protect aluminum, but also are depleted relatively quickly in service. They're also somewhat abrasive (being based on silicon-sand), so they've been implicated in water pump seal wear. Advocates say tests show silicates last longer than was commonly believed. And with the latest seal materials, they actually do a better job of protecting the water pump, because they both resist cavitation erosion-corrosion and "repair" any that occurs.
OAT coolant (orange or pink) contains no silicates and no phosphates. It's a blend of two or more organic acids, a specific class of inhibitors with slow-acting, long-life properties. Texaco's Havoline Dex-Cool (also sold under the Goodwrench label by GM) was the first example. Prestone and Peak also have introduced OAT coolants that are chemically compatible with Dex-Cool.
Conventional Japanese coolant (green or red) contains no silicates, but has a heavy dose of phosphates and other inhibitors, including a modest amount of one or two organic acids.
Conventional European coolant (blue or yellow) contains a low dose of silicates and no phosphates, but does include other inhibitors, including one organic acid.
Hybrid European coolant (blue or green) is similar to conventional European, but with a much greater dose of organic acids. It's a balanced formula designed to have the silicates provide the primary protection for the aluminum, then allow the organic acids to provide long-term protection.
Hybrid American coolant (green or orange) contains a moderate dose of silicates, plus a blend of organic acids.
See also: “Coolant Color and its Significance” http://www.englefieldoil.com/PDF/coolantcolor.pdf
From “Keeping It Cool” ~ by Paul Weissler“ http://silverstone.fortunecity.com/ferrari/464/coolant.htm
Conventional American coolant (green or gold) contains silicates (a long-used aluminum corrosion inhibitor) and other inhibitors. Silicates work quickly to protect aluminum, but also are depleted relatively quickly in service. They're also somewhat abrasive (being based on silicon-sand), so they've been implicated in water pump seal wear. Advocates say tests show silicates last longer than was commonly believed. And with the latest seal materials, they actually do a better job of protecting the water pump, because they both resist cavitation erosion-corrosion and "repair" any that occurs.
OAT coolant (orange or pink) contains no silicates and no phosphates. It's a blend of two or more organic acids, a specific class of inhibitors with slow-acting, long-life properties. Texaco's Havoline Dex-Cool (also sold under the Goodwrench label by GM) was the first example. Prestone and Peak also have introduced OAT coolants that are chemically compatible with Dex-Cool.
Conventional Japanese coolant (green or red) contains no silicates, but has a heavy dose of phosphates and other inhibitors, including a modest amount of one or two organic acids.
Conventional European coolant (blue or yellow) contains a low dose of silicates and no phosphates, but does include other inhibitors, including one organic acid.
Hybrid European coolant (blue or green) is similar to conventional European, but with a much greater dose of organic acids. It's a balanced formula designed to have the silicates provide the primary protection for the aluminum, then allow the organic acids to provide long-term protection.
Hybrid American coolant (green or orange) contains a moderate dose of silicates, plus a blend of organic acids.
See also: “Coolant Color and its Significance” http://www.englefieldoil.com/PDF/coolantcolor.pdf