Block Heater Recommendation

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Gdavid

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Graceland
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Mainship 34 MK1
I'm planning to install a block heater, preferably the circulating type. Does anyone have recommendations for a particular model? I'm leery of anything with a plastic body. Thank you.
 
Rarely needed. why do you want to add one?

pete
 
Rarely needed. why do you want to add one?

pete

My old perkins emits blue smoke on startup, worse in cooler weather, little smoke at operating temperature. No significant oil consumption and it starts immediately, more than anything else, it is embarrassing. I doubt it will solve it completely but should certainly improve matters.
 
I have a block heater on my John Deere 4045. Rarely use it, but when needed, it makes a big difference.

My recommendation would be to see if the manufacturer offered one. While it may no longer be available, it would certainly be a good guide. I chose to use John Deere's block heater rationalizing they did research to determine what would work best.

Ted
 
This is a bit extreme and may not work on a boat. :ermm:

Yeah, I think I'll skip that approach.

Thanks for the input everyone, it looks like perkins never offered one, they used their combustion air heater (burns diesel) instead but that really isn't necessary or addresses my needs but a heater that replaces a freeze plug is probably the best way to go. I was thinking of tying into the coolant loop to my water hater, but that flow would probably be restricted by the thermostat and just introduces more points of failure. The freeze plug style are simple and cheap, should work fine. Thank you for pulling my head out of my backside.
 
I'm planning to install a block heater, preferably the circulating type. Does anyone have recommendations for a particular model? I'm leery of anything with a plastic body. Thank you.

Our DD 6v92's came with Hotstart in block heaters. They work great. Keeps the engine room nice and consistent temp through the non-summer months and helps a lot with cold starts and reducing smoke. They do have a plastic covering but it's never seemed to be an issue. Engines are 25 years old and have 2350 hours on them. YMMV

https://www.hotstart.com/solutions/in-block-heaters/
 
Our DD 6v92's came with Hotstart in block heaters. They work great. Keeps the engine room nice and consistent temp through the non-summer months and helps a lot with cold starts and reducing smoke. They do have a plastic covering but it's never seemed to be an issue. Engines are 25 years old and have 2350 hours on them. YMMV

https://www.hotstart.com/solutions/in-block-heaters/

Perfect, just ordered one. My dock mates will surely be grateful to you.
 
I see I am an hour late (as usual :)).
I also recommend the Wolverine oil pan heater. The one I used on my Cummins 6BTA 330 HP engine was 250 watts. It kept the oil (and rest of the engine and ER) warm, and helped with cold starts, early oil flow (right after a cold start), and kept the ER warm and dry in the winter.
At 250 watts, not much draw, left it on 24/7, and it worked very well.
 
If you have a closed coolant system look at hotstart bublers. Can get a 1000w or maybe a 500w. Tie it into your coolant system. Universal is another brand. Use them in stand by generators to keep the motor warm.
 
Our DD 6v92's came with Hotstart in block heaters. They work great. Keeps the engine room nice and consistent temp through the non-summer months and helps a lot with cold starts and reducing smoke. They do have a plastic covering but it's never seemed to be an issue. Engines are 25 years old and have 2350 hours on them. YMMV

https://www.hotstart.com/solutions/in-block-heaters/

Had Kim Hotstarts on my DD 8v71s, which loved them....easy starting, little smoke. I now have them on 6bt Cummins which don't need help with starting or smoke, but they keep the engine room warm and dry during the cold months.
 
what hasn't been mentioned (unless I missed it) is these heaters also help stop corrosion in the engine room. They heat the block and help stop condensation. I'd use them even in the off season in Florida.... The wolverine pad heaters are very easy to add to any engine...and by all reports, they work really well.
 
What would be preferred, a block heater or an oil pan heater? I would think that nice warm juicy oil would do more for reducing premature wear of cylinders and rings (dry startups)
 
I see I am an hour late (as usual :)).
I also recommend the Wolverine oil pan heater. The one I used on my Cummins 6BTA 330 HP engine was 250 watts. It kept the oil (and rest of the engine and ER) warm, and helped with cold starts, early oil flow (right after a cold start), and kept the ER warm and dry in the winter.
At 250 watts, not much draw, left it on 24/7, and it worked very well.
I am not much concerned with cold starts (Lehman 120s). In the springtime, they both start easily meaning that they start within three seconds of cranking at around 50 degrees. In warmer temps, they fire up almost instantly. I do like the idea of the Wolverine heater keeping an engine room warm. So, opinions please, would a single heater do? My thinking is if a heater on a single-engined boat keeps an engine room warm, why wouldn't a heater on one engine heat the other engine as well along with the engine room, eventually?

Why do I ask? My boat is kept in the water at the Annapolis, MD latitude. I do not winterize except to drain the hose to the anchor washdown spigot on the bow and the supply line to the icemaker on the aft deck. However, this will be the first year in six that we have not lived aboard over the winter. I will be draining all of the hot and cold water supply lines with an air compressor. Prior experience has seen engine room temps never going below 35 degrees even in the one winter we did not live aboard. Still, I like the idea of keeping the engine room warm with a passive heater where much of the running feet of water line lives.

My plan is to open the drain on the hot water heater and let the water gravity drain through the heater aided by compressed air at the two head sinks and the galley sink starting with the galley sink as it is at the highest level. Any flaws in my thinking?

And, no, I have no interest in, or need for, any anti-freeze anywhere except in the toilet bowls.

Edit: I mentioned one winter not living aboard. That was the winter I observed an ER temp not going below 35 degrees. It was measured during a five-day January cold spell when the air temps did not get out of the single digits. I visited the boat on the third day and not knowing how much longer the very cold temps were going to last and not knowing whether more days of cold would lower the ER temp even further, I started a ceramic heater. Eighteen hours later, with the air temps outside still in the single digits, the engine room (and the engine blocks) were warmed to 65 degrees. However, with the engine room almost totally immersed in a water bath above freezing, the engine room would have been fine anyway.
 
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What would be preferred, a block heater or an oil pan heater? I would think that nice warm juicy oil would do more for reducing premature wear of cylinders and rings (dry startups)


Ideally, you'd want both, although if you leave the oil pan heaters on 24/7 it'll warm the blocks and coolant as the heat rises into them. Getting the coolant and block warm will help with ring wear, warm oil will help bearing and valvetrain wear at startup as well as helping ring wear. And both thinner oil and warmer cylinders make for easier starting.
 
I am not much concerned with cold starts (Lehman 120s). In the springtime, they both start easily meaning that they start within three seconds of cranking at around 50 degrees. In warmer temps, they fire up almost instantly. I do like the idea of the Wolverine heater keeping an engine room warm. So, opinions please, would a single heater do? My thinking is if a heater on a single-engined boat keeps an engine room warm, why wouldn't a heater on one engine heat the other engine as well along with the engine room, eventually?


1 heater would definitely make a noticeable difference, although I could never do it that way. The lack of symmetry in heating would drive me crazy, as 1 engine would always be warmer than the other at startup. Heating both engines (even if you then use smaller heaters) will keep more even temperatures through the engine room in cold weather as well.
 
What would be preferred, a block heater or an oil pan heater? I would think that nice warm juicy oil would do more for reducing premature wear of cylinders and rings (dry startups)

In my case I want to heat the water jacket/block of the engine to help the oil control rings do their job on startup. If I was operating in extreme temps I would want to heat the oil pan as well but I just don't expect to use the boat when it is that cold. The amount smoke at startup between mid-summer versus fall spring and fall is pretty significant. Years ago I worked on a boat with 671's and block heaters made a huge difference as well as keeping the engine room dry.
I was planning to tie into the circuit to my water heater but upon further inspection, it appears to be restricted by the thermostat until it opens (on my particular installation) so a heater that replaces a freeze plug should meet my needs as well as take less engine room space. Thanks to all responses.
 
Ok just got a new to me 05 GB 42 w single JD 6068. timely thread, maybe.... boat's been here its whole life and does not appear to have any sort of block or oil pan heater. here is a very basic question - where exactly do you attach the wolverine or similar oil pan heater, and if it is literally on the bottom of the engine (rather than on the metal "pan" under it (basically just a catch basin in the bilge), how do you do that? can't really get under there to squeegee etc. I read the wolverine directions; does not look like its meant to go on upside down, but attaching it to the bottom of the basin seems like you'd be heating mostly the hull?

this won't be my first project but the "safely heating the boat while i'm not on it" issue is on my list... thanks. more dum Qs to follow
 
The pan heater needs to go on the bottom of the sump. (where the oil collects) In boats that can be a problem due to clearances. It heats the oil and the ambient heat rises up through the engine and heats the whole block and water jacket. Its a slow cook. Some of them even have a built in thermostat turning on at 170 and kicking off a 200 so there not cooking all the time. This will increase the room needed to install.
 
I installed an oil pan heater on my engine. It was an awkward process as you are doing it blind without much clearance. I got a glass mirror tile and set in under the oil pan so I could see what I was doing, or more accurately what I was going to do and what I did.

It is on 24/7 except in the summer. It keeps the ER dry and not cold in the winter.
 
There is some good info on Tony Athens' website (sbmar.com) regarding why he prefers an oil pan heater over a traditional "block heater" (in the forums and under Tony's Tips). Most block heaters require much more power (eg. like 1200 - 1500 watts compared to 250 watts for the oil pan heater) and on a 30 amp boat, can use half of the amperage available (and that is the block heater for one engine).

The oil pan heater "glues on" to the "bottom of the engine" on the oil sump. I installed mine (using a mirror and by "feel") and there was only 5 to MAYBE 6 inches of clearance to the ER floor.
From memory, I cleaned the bottom of the oil sump (pan) with solvent, slightly roughed up the surface with sandpaper (and cleaned again) to ensure better adhesion, and then glued on the pad. Then the edges are sealed with a "goop" (supplied with the pad). Plug it in and that's about it.
As others have stated, it will take a few hours of use to heat things up, but with so small a power draw, it can safely be left on 24/7 in the colder weather.

Others have explained the many benefits, and this little heater (if left on long enough) does heat up the oil, the block, the internals (bearings, etc.), and the coolant (and the overall ER to a point, keeping it dry).
If I had twin engines, I would install one on both engines. These heaters are not that expensive, and even with 2 on, would only draw 500 watts (or about 4 amps still leaving about 20 amps available on a 30 amp boat).
Just my thoughts.
 
1 heater would definitely make a noticeable difference, although I could never do it that way. The lack of symmetry in heating would drive me crazy, as 1 engine would always be warmer than the other at startup. Heating both engines (even if you then use smaller heaters) will keep more even temperatures through the engine room in cold weather as well.
As I said, I am not concerned about starting. I just want to cheap out and use only one Wolverine if it can eventually get everything up to temp.
 
On my Cummins engines I have Wolverines installed on the sides of the oil pan. Since the oil pan is aluminum it conducts the heat well, they don't have to be on the bottom. I've added a thermal controller I purchased off Amazon with a thermocouple mounted to the block on one engine. That way they switch off when the engine is running and only come back on when the block drops down to around 70F. They work great to keep things warm and don't use much power the way I have them setup. Probably the best thing you can do to prevent corrosion down in the engine room during the winter, even in San Diego.
 
+1 on the in block heaters. I had a lehman 120 diesel and boat year round in NE. Had 2 in block heaters mounted in freeze out plugs.

I installed a thermostat in the engine compartment that would kick the heaters on below 50 degrees.

Was just really nice and not expensive at all. (I got the heaters from a tractor shop
 
I installed Kat Block heaters on my old CAT 3208 TA's and WOW, what a difference on those cold starts. I went from the smoke-show to almost NOTHING...
Added benefit, since my engines are mid-ship, the heaters keep the entire boat at a fairly comfortable temp, all year around. I also added temp controlled switches. That way when the engines warmed up or it was already warm outside, the heaters turn themselves off... :) The temp sensors I got are also wifi enabled and I can see them from my phone on their app.
Pic below, right side is block heater off, left is on. This wasn't a particularly cold day, so not as bad as it can get when REALLY cold outside.
One of the other pics shows the outside temp at the marina and what the block heaters keep the boat at, even in 24° weather!!!

https://www.fivestarmanufacturing.com/pdf/kats_2020_catalog_complete_web-(1).pdf
 

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For those with twin engines using both block heaters, beware of the power draw (can be 12.5 amps each heater) and the capabilities (safety in mind) of your shore power cord and connections.
For those with 30 amp boats, 2 block heaters running don't leave much if any room for powering anything else safely.
It is a good idea (in general) especially at this time of year, to keep an eye on your overall power draw, and ensure your electrical cord and connections are in good condition, and are not heating unduly (use an IR thermometer or infared camera). :)
Over the years, I have seen lots of examples of cord and connection damage from overheating (could be called "near misses"), as well as several boat fires caused by this. Usually in the cold weather. You cannot safely run the system at full capacity (eg. 30 amp draw) continuously. Safety first! :)
 
I'm planning to install a block heater, preferably the circulating type. Does anyone have recommendations for a particular model? I'm leery of anything with a plastic body. Thank you.

I have CAT 3406E, 800 HP and use Wolverine pads, low amp draw, great for the PNW.
 
One of the most common defects I find with block heater installations, even by professionals, is unenclosed AC splices. All AC butt splices and terminals must be enclosed in a junction box if you want to be ABYC compliant and avoid electrocution and fire hazards.
 

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