Block Heater

[GoldenDawn]

I have a new-to-me Kadey Krogen 42 with 135 Lehman. It has a block heater that keeps the engine about 100 deg F. The previous owner suggested keeping it on during the winter (Pacific NW) but our summers are not that much different than winters (~50 F water temperatures year round). The block heater keeps the engine room toasty and I am not having any unusual zinc issues.

So is there a down side to leaving this on 24/7?

 

[FF]

Cost of electric,

but the advantages would be worthwhile even at 50c a KW.

 

[C lectric]

As FF said.

If you decide later you don't need all that heat during the warmer season, put it on a timer. The engine and room will still be kept warm but not waste power.

 

[FF]

If you decide later you don't need all that heat during the warmer season,

IF the temperature drops to the dew point , where you see water on some surfaces in the early AM, since its cooler in the bilge than on deck, you may have condensation inside the cylinders.

 

[Jay N]

GoldenDawn wrote:
I have a new-to-me Kadey Krogen 42 with 135 Lehman. It has a block heater that keeps the engine about 100 deg F. The previous owner suggested keeping it on during the winter (Pacific NW) but our summers are not that much different than winters (~50 F water temperatures year round). The block heater keeps the engine room toasty and I am not having any unusual zinc issues.

So is there a down side to leaving this on 24/7?

100 deg F is a little hot if your only goal is to keep moisture out of the engine room.* Consider a pan warmer of around 250 watts.* Cheaper to operate, and should have more durability than a coolant type heater.

If you want to decrease the performance of your existing block heater, consider installing a simple timer.

 

[FF]

Consider a pan warmer of around 250 watts.

Beware of the simple magnetic pan warmers , but a unit installed inside the pan with a large surface area is fine.

The small magnetic units can burn the oil and create chunks of carbon in the pan as the contact area is very small.

 

[koliver]

Here in BC, (Vancouver), we get ice on the water in the marina about one year in four. When we get that ice, it can be 1/8 in to 1/2 in thick. Outside temp at the coldest is rarely below -5 (deg C). I have had a boat in the water here every winter since 1977. In the early years I used a light bulb, 100watts. After selling the first boat, I acquired one with a hot water tank in the ER. Since then, leaving the hot water tank plugged in has kept that and the present ER plenty warm enough to prevent condensation and keep things dry and clean. The engine coolant is "anti-freeze" so can tolerate -10 or lower engine temp. The ambient temp is so the humid winter air doesn't condense and cause mildew and damp.
Some have block heaters, but for the purpose of getting the engine up to operating temp more quickly and bypassing the dense cloud of smoke some low injection pressure engines emit when cold. Your Lehman, if really old, may be such an engine. In the Marina where I keep my boat, old CAT 3208s were the worst for that phenomena, and only marginally better with block heaters.
If you are on metered Hydro, you will quickly see the downside in your bills. If on a flat rate, your marina is getting the downside.
Is there an up side? the only way to know is to try leaving the heater on, then don't and report whether there was any improvement in starting, or in getting past the cloud of smoke. The rest of us can only take wild guesses about any up side.