Coolant Recommendation?

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
I need to drain my cooling system for a hose replacement, so this is a good opportunity to change the coolant. It's a Westerbeke 38B-FOUR, based on a normally-aspirated Mitsubishi four cylinder diesel.

I have previously read about the different extended life coolants (ELC) and recall some horror stories about certain kinds, and the effects of mixing them, and so on. I can't recall the details. I am hoping someone here can recommend a suitable coolant type for my engine. Here's what the manual says:
ENGINE COOLANT
WESTERBEKE recommends a mixture of 50% antifreeze and 50% distilled water. Distilled water is free from the chemicals that can corrode internal engine surfaces. The antifreeze performs double duty. It allows the engine to run at proper temperatures by transferring heat away from the engine to the coolant, and lubricates and protects the cooling circuit from rust and corrosion. Look for a good quality antifreeze that contains Supplemental Cooling Additives (SCAs) that keep the antifreeze chemically balanced, crucial to long term protection. The distilled water and antifreeze should be premixed before being poured into the cooling circuit.

PURCHASING ANTIFREEZE
Select a brand of antifreeze specified for diesel engines. Antifreeze specified for diesel engines contain a special additive to protect against cavitation erosion of the engine's cylinder walls. Prestone and Zerex are two nationally known brands that offer antifreeze specifically for the use in diesel engines. Select the pre-mix variety so that the correct mixture will always be added to the cooling system when needed. Change the antifreeze mixture according to the MAINTENANCE SCHEDULE in this manual.
So, can anyone translate that into a specific product recommendation?

Capacity: the manual says 6 quarts, but mine has a water heater added, plus a second, remote pressure tank. How much extra do you think I'll need?

Thanks in advance,

jv
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
Suggest contacting Westerbeke directly (link below) for coolant recommendation and purchase by the quart , if possible. When I recently purchased coolant for my Yanmar I bought a gallon of Yanmar coolant, albeit probably overpaid.....and have extra coolant for the next change-out.

 
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Jun 21, 2004
2,532
Beneteau 343 Slidell, LA
Suggest contacting Westerbeke directly (link below) for coolant recommendation
I changed my coolant a couple of years ago and used the recommended coolant that was suggested in the Yanmar manual.
They advised Yanmar coolant or equivalent; one that was listed as an acceptable substitute was Havoline extended life coolant (red stuff).
The previous owner was using green coolant; therefore, I had to flush the system several times with distilled water, prior to converting to Havoline. One gallon was more than adequate because it had to be diluted with 50% distilled water. Pay close attention because some coolants come pre-diluted and dont require mixing; others are concentrated and require dilution.
 
May 24, 2004
7,129
CC 30 South Florida
Anti freeze formulated for Diesel Engines? Is that a marketing ploy or is there really such a thing. Buy a good quality antifreeze from a reputable manufacturer and mix it at a 1:1 ratio with distilled water. I get the distilled water at Pharmacies as they also use the same to prepare prescriptions. Water provides the cooling and the antifreeze chemicals the protection against freezing and corrosion. If you use 60% antifreeze to 40% water you will be reducing the cooling capacity and if you use the inverse mix you reduce the protection. Stick to 50% equal parts for designed levels of cooling and protection.
 

NYSail

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Jan 6, 2006
3,048
Beneteau 423 Mt. Sinai, NY
I used shell rotella elc at the recommendation of yanmar mechanic in Newport (mike the mechanic). Flushed several times changed all hoses thermostat and all good. I bought premixed so no dilution necessary. Add what they recommend then keep filling to compensate for water heater etc.... always good to have a little extra just in case.

Good luck
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
Our engine came from the factory with the original Dex-Cool formulation. It was HORRIBLE.... Dex-Cool was reformulated but our engine came from the factory with the old stuff, when it shipped from Westerbeke. It caused the engine to sludge up very badly. These days, after discussing this with the Mitsubishi industrial distributor because Westerbeke lacked any detail, I use a diesel specific antifreeze. I have been using Rotella Ultra ELC for many years as I can get it locally at our NAPA location where we have a commercial account. I change it annually and it's inexpensive, about $1 - $2 more than a typical auto coolant.

Be careful however, as you do not want to mix coolants unless the bottle says something to the effect of; "all makes all models". Peak, Prestone, NAPA etc. all have an "all makes all models" coolant. If you don't know what coolant you have it is best to use one that can be mixed with any existing coolant. Most older sailboat diesels we come across are using a "green" coolant except for Yanmar, and some other newer engines that use an HD diesel type coolant, which is usually red/pinkish.

When I switched out the Dex-Cool I had to run a full Rydlyme purge, then flush the engine, then make the switch to an HD coolant which has been Rotella Ultra ELC.

Don't even get me started on the local diesel mechanic who went around switching all his EG customers to a PG "green" engine coolant, thinking it was better for the environment, then not marking the engines as such.Boat yards & owners were then adding green EG to the green PG.... Talk about an $$$$$$$ oops..
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Thanks, @Maine Sail for the specific recommendation. And thanks to everyone else who replied.

I don't know what's in there now, but it's red, almost an orange-like red. I hate the thought of flushing it, as it's a pain to fill this system, with the second, remote pressure tank. And I'd have to bring a ton of distilled water with me. Would it be OK to use well water for the flushing, draining it, of course, to fill with the new stuff?

Don't even get me started on the local diesel mechanic who went around switching all his EG customers to a PG "green" engine coolant, thinking it was better for the environment, then not marking the engines as such.Boat yards & owners were then adding green EG to the green PG.... Talk about an $$$$$$$ oops..
It's my understanding that typical coolant is not harmful to the marine environment. Is that so?
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
I need to drain my cooling system for a hose replacement, so this is a good opportunity to change the coolant. It's a Westerbeke 38B-FOUR, based on a normally-aspirated Mitsubishi four cylinder diesel.
Ooooooooh, sounds like this is not a regular maintenance item :doh:.

I change mine every two years because I'm too lazy to drain all of the external hosing and Domestic hot water heat exchanger. Only the block gets drained and quickly too. I figure the turnover is sufficient to keep the corrosion inhibitors and other etceteras up to a good % concentration.
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Ooooooooh, sounds like this is not a regular maintenance item :doh:.

I change mine every two years because I'm too lazy to drain all of the external hosing and Domestic hot water heat exchanger. Only the block gets drained and quickly too. I figure the turnover is sufficient to keep the corrosion inhibitors and other etceteras up to a good % concentration.
There are heavy duty coolants that have compatible additive boosters you can add.
 

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Ooooooooh, sounds like this is not a regular maintenance item :doh:.

I change mine every two years because I'm too lazy to drain all of the external hosing and Domestic hot water heat exchanger. Only the block gets drained and quickly too. I figure the turnover is sufficient to keep the corrosion inhibitors and other etceteras up to a good % concentration.
That makes sense like the guys I knew as a kid, who had cars that leaked and burned oil, like a quart a month. They never changed the oil, saying it was being renewed by all the oil they added. But, they weren't ever draining the crud.
 

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
I have been using Rotella Ultra ELC for many years as I can get it locally at our NAPA location where we have a commercial account.
I bought this today; had to order it for next-day pickup at my local NAPA (which I love), along with a new NAPA Gold oil filter. There's always some kind of discount online, got 10% off on 3 gallons of the pre-mixed stuff. Thanks for the recommendation.
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Shell Rotella Ultra ELC has become virtually unobtainable. I'm thinking it's out of production. NAPA no long lists it. The only sources I found were one place online where I'd have to buy six gallons, and someone on eBay who wants stupid money for it.

So, I decided: WalMart Super Tech Prediluted 50/50 Heavy-Duty Extended Life Antifreeze/Coolant, 1 Gallon. $10.96 per gallon. The heavy duty is not available as a concentrate, but at this price, I love the convenience of pre-mixed anyway. Check this from their web page:

Super Tech Prediluted 50/50 Heavy Duty Extended Life antifreeze/coolant is a nitrite-free organic acid technology (OAT) that meets or exceeds ASTM requirements. Free of phosphates, borates, nitrites, silicates, and amines. It provides up to 1,000,000 miles or 20,000 hours of protection and is recommended for initial fill or top-off in all gasoline or diesel engines.
Super Tech Prediluted 50/50 Heavy-Duty Extended Life Antifreeze/Coolant, 1 Gallon:
  • Ready to use
  • Extended service life — up to 1,000,000 miles, 8 years or 20,000 hours of off-road use
  • Free of phosphates, silicates, nitrites, amines, and borates
  • Prevents pitting caused by cavitations and corrosion of brass, copper, solder, steel, cast iron, and aluminum
  • Extended life corrosion protection for aluminum and all other engine metals
  • High-quality defoamer which is non-harmful to hoses, plastics, or gaskets
  • Great for mixed fleets — approved for use in heavy duty and light duty engines
  • Meets or exceeds ASTM 6210. Ideal for CAT EC-1, Cummins, Detroit Diesel, Navistar, or mixed fleets
  • Compatible with the major American brands of organic acid technology coolants on the market today
Compare to the "regular" Super Tech ELC which is rated for 150,000 miles. Wow.

Such a deal! Three gallons ordered, will be delivered to my house today for free (WalMart+ membership). That's enough to fill my system just about twice. I want to have extra on board in case I blow a hose or something while cruising.
 
Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
Diesel engines often require an additive that prevents cavitation pitting of the cylinder sleeves. We use diesel rated coolant at work or we add the diesel supplement to regular coolant. We have one 28 liter V12 Cummins engine that wasn't well cared for and it has seized up. The coolant passages look terrible. As time permits we are disassembling this engine. It has a leak in the water to air after-cooler and I suspect a hole in a cylinder sleeve. I suspect the tech was using regular coolant and tap water.

A few years ago my boss decided that we would all switch to Peak Final Charge OAT coolant. All of the techs are now dealing with small leaks everywhere. Most of the leaks are at hose connection, some from water pumps and some from radiators. Some of the water pumps will stop leaking after a few hours of run time. I tighten the hose clamps but that often isn't enough to stop the flow. The radiators get replace or repaired. I won't use this stuff in my personal equipment.
 
Last edited:

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Diesel engines often require a additive that prevents cavitation pitting of the cylinder sleeves. We use diesel rated coolant at work or we add the diesel supplement to regular coolant. We have one 28 liter V12 Cummins engine that wasn't well cared for and it has seized up. The coolant passages look terrible. As time permits we are disassembling this engine. It has a leak in the water to air after-cooler and I suspect a hole in a cylinder sleeve. I suspect the tech was using regular coolant and tap water.

A few years ago my boss decided that we would all switch to Peak Final Charge OAT coolant. All of the techs are now dealing with small leaks everywhere. Most of the leaks are at hose connection, some from water pumps and some from radiators. Some of the water pumps will stop leaking after a few hours of run time. I tighten the hose clamps but that often isn't enough to stop the flow. The radiators get replace or repaired. I won't use this stuff in my personal equipment.
Wow, thank you for your expertise! There are so many experts on this forum!

So, what do you think of the Super Tech HD ELC? Did you have a chance to read the spec I posted?

Thanks,

jv
 
Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
I have not read the specs. If it's rated for use in diesels it should say that. Although I'm not using NAPA diesel coolant I recommend it because it specifies that it has the required diesel supplement in it and it's easy to find.
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
I have not read the specs. If it's rated for use in diesels it should say that. Although I'm not using NAPA diesel coolant I recommend it because it specifies that it has the required diesel supplement in it and it's easy to find.
Thanks again. Yes, it says "Meets or exceeds ASTM 6210. Ideal for CAT EC-1, Cummins, Detroit Diesel, Navistar, or mixed fleets."

I looked at ASTM 6210, and it's impressive.

I'm going to look into Supplemental Coolant Additives (SCA) for maintenance.

jv
 
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