Coolant Recommendation?

jviss

.
Feb 5, 2004
4,627
Tartan 3800 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
3,777
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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Likes: BigEasy
Jun 21, 2004
1,884
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
6,790
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
2,741
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
11,436
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
4,627
Tartan 3800 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
3,904
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
4,627
Tartan 3800 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
4,627
Tartan 3800 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

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Feb 5, 2004
4,627
Tartan 3800 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.