Warm starts, Circulating Block Heaters

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

RowboatBob

Member
Joined
May 9, 2017
Messages
17
Location
USA
It has been customary on all our tug boats (in Seattle and Alaska) to install small diesel fired furnaces that that will keep warm (hot) water circulating through the engine block, even through an element in the Oil Pan. This results in never having a cold start issue with the mains, shorter warm up times, less smoke and soot.
One advantage to this is that the engine room, and most of the entire cabin space, stays nice and warm/dry. But these are huge masses of iron acting as the heat source.

My question: Does this seem like a do-able application for a small trawler (i.e; Nordic Tug 37) and are there other alternatives that are common practice in the pleasure boat industry, without relaying on a simple block heater through a freeze plug. Just trying to wrap my head around the pros and cons of the concept for this application.

We have some great engineering types on staff that often times custom make the furnaces/exchangers for the tugs, but I hate to dominate their time on my toys.

Thanks in advance for your opinions!
 
It has been customary on all our tug boats (in Seattle and Alaska) to install small diesel fired furnaces that that will keep warm (hot) water circulating through the engine block, even through an element in the Oil Pan. This results in never having a cold start issue with the mains, shorter warm up times, less smoke and soot.
One advantage to this is that the engine room, and most of the entire cabin space, stays nice and warm/dry. But these are huge masses of iron acting as the heat source.

My question: Does this seem like a do-able application for a small trawler (i.e; Nordic Tug 37) and are there other alternatives that are common practice in the pleasure boat industry, without relaying on a simple block heater through a freeze plug. Just trying to wrap my head around the pros and cons of the concept for this application.

We have some great engineering types on staff that often times custom make the furnaces/exchangers for the tugs, but I hate to dominate their time on my toys.

Thanks in advance for your opinions!

Yes,useful for small trawler engines as well. No need for furnace setup. A small wolverine heat pad, mounted to oil pan does the trick. Cuts down on condensation inside as well. SBAR marine sells them (Seaboard Marine). A couple of hundred bucks well spent. Truck supply houses have the block immersion types as well. your choice.
 
I have the wolverine pads on my 6bta's and they stay warm, easy to start and the engine room stays warm. Two of them draw about 4 amps 120v while on.
 
I second, third or fourth the Wolverine heater for recreational engines.


A diesel fired coolant heater would be way overkill unless you need the heat for living inside the boat in cold weather. A 250 watt Wolverine heater will work fine in most climates unless you plan to go out in subfreezing temps. The smallest Espar coolant system heater can only be turned down to 1,300 watts of heat output.


David
 
I have block heaters on my twin Detroit 671s. They start fine in below 0°F. With the block heaters I use a Thermocube, on at 35°, off at 45°, when temps are very low as an insurance against freezing. They will switch 1500 watts. In about 25°F temps, the block heaters warm the engine room to about 70° w/o the Thermocubes.

I also have a diesel fired boiler for my hydronic system. I can circulate that coolant thru the engines. Much more expensive to run than the block heaters. I have the boiler plumbed into the mains so I can have free heat when cruising.
I wouldn't leave a oil furnace running w/o someone on board. The tugs I owned used electric oil and block heaters. If a crew was on board a generator was running anyway and the extra fuel usage wasn't enough to notice.
Thermocube is under $20 on ebay. There is also a hotter one designed to turn on AC.
 

Attachments

  • Thermocube.JPG
    Thermocube.JPG
    10.5 KB · Views: 43
We have a Hurricane diesel furnace in our boat that is plumbed thru the hot water tank and the two main engines. During the colder weather the engines start right up with no smoke and the engine room will stay 50-70 degrees, and dry. Even in the warmer months while cruising the north coast of BC and SE Alaska we find ourselves needing some heat in the mornings. So the engines benefit from the hot water pretty much all year long.
 
Well, I knew I would find the right answers and solutions here. I had not heard of these Wolverine heating pads. Should do the trick. I'm all about keeping machinery spaces warm and dry, as well as interior spaces.

Thanks guys, all great input.Really appreciate ALL the responses.
 
You can also get 240Vac immersion heaters at 1000W and run them on 120Vac, draws about 1/4 the power. A couple hundred watts is all you need.
 
I bought a Wolverine for my generator directly from them . Utterly delightful people to do business with. I am sworn to secrecy about the little favor they did as a result of some casual conversation, but let's just say they are very nice people.

Looks like they've now sold out, coincidentally to Phillips and Temro. I had their Zerostart immersion heaters on my DD 8v92's care of a PO. Also good folks when I needed some help. No need for circulation on those. My set up included an integrated thermostat which tapped into the coolant tank. I loved those dang things. Two side benefits beyond clean fast starts: the warming of the ER (and due to the design of our old Hatteras MY) and lower level, plus they kept the big hunks of iron a consistent temp regardless of the weather. Even in North Carolina I kept them on at least 6 months a year.
 
I also like the oil pan heaters. 250W is plenty on my Cummins 5.9l engine in Puget Sound. I did it to keep condensation down in the ER not for any issues with cold starts. Works great.
 
Another company to look at is. Hotstart. They make all kinds of different stuff from battery heating pads to oil/ coolant heaters. 99% of out gens come from the factory with a jwh from them. If you do go with a coolant heaters. Get a immersion switch and put it in the upper part of the block. Its a much more precise than the ones mounted in the jwh.
 
I put a block heatet in my 4 cylinder John Deere. Gets the coolant up to 110 degrees and the engine room about 60 degrees.

Ted
 

Latest posts

Back
Top Bottom