Pad Heaters What Size?

[whaler23]

These seem awfully small(see link below)for an 8V71N so I'm wandering what is the appropriate size for reasonable start ups in cold temps. Boat is used on the Chesapeake Bay through the end of each year. Winterizing occurs between Xmas and New Years Day. In addition I have a 1500W permanent Xtreme Bilge Heater that keeps everything else warm as necessary but don't let it run when I'm not on the boat so that heater takes a day to heat up those engines...

http://www.dieselproducts.com/cgi-bin/online/storepro.php

 

[lumina]

Hi All,

I actually posted something about this a few weeks ago.

I have 8V71 Naturals and I have one 250W WOLVERINE oil pan heater on each engine. Little bigger than a credit card. They produce a lot of heat and keep the engine oil temp at appx 100 degrees and it radiates through the whole engine. Works fine in new england in april/may or october/november.

http://www.wolverineheater.com/

Great well made product.

 

[whaler23]

Do you leave them on all the time?

 

[lumina]

Scott,

As per the wolverine folks I leave them on all of the time except when the engines are running. They are each connected to their own circut breaker so as part of the departure process we just flip them off, once wer're back in the slip we flip them on.

Give them a call they are really nice people. Mention my name I'm sure they will remember me.....Gene Ingalls

 

[whaler23]

Thanks Gene, will do.

 

[Genesis]

I used two 250W Wolverines on each of my 6V92s.

One on the side of the oil pan (the bottom had the Detroit embossed design and you MUST HAVE 100% contact or the pad will burn up!) and the other on the side of the oil cooler housing.

I rigged thermostatic controls for them so they came on with the engine room temperature under about 70F (settable; a basic thermostat) and wired the trigger circuit through the hobbs switch so they were automatically disabled when the engine was started (replaced the hobbs switch with a dual-pole model that had a normally-closed contact as well as the normally-opened.)

Instant smoke-free starts were obtained with this strategy all the way down to way below any temperature I was wanting to run the boat with them, yet the engines themselves felt only a bit warm to the touch.

 

[REBrueckner]

You have two choices...something in the 250 watt range mentioned above if left on a considerable period of time before a cold weather start...or if left on all the time....or you can use a larger heater, around 1200 watts, typical of DD coolant heaters which will warm the engine enough for an easy start in 45degree temperatures in about 45 min to an hour....

 

[Diver Down]

Glad to hear that you guys have had good luck with the Wolverine heaters. I rec'd a call this morning from their Sales Manager (Lloyd Megenity) regarding my inquiry on heater sizing. Very informative conversation and I appreciated the personal attention even though I had not asked for a call.

My problem at this point is locating an accessible and large enough space on the oil pan (8V71) to install their Model 40 heater. Lloyd said that we should insulate between the heater and any fiberglass that may be closer than 6 inches from the heater. Where exactly did you find such a space?

FWIW, Lloyd also said that insulating would not be necessary on the small, Model 9 (250 watt) heater I plan to use on the Onan.

 

[whaler23]

This is what I just ordered from the Wolverine website. I figured 500 watts on a thermo cube plug would be my best bet. That way when I get down to the boat I can turn on the engine room heater and between that and the thermo controlled pads I should be in good shape by the next morning to fire em up...

MODEL NO. QTY CHARGE DESCRIPTION
W018 1 19.95 Thermal Cube Plug
W05 2 89.95 Model 40 500 WATTS 110

 

[GJH]

Which Onan do you have? I'd like to install one on mine, but there seems to be very little clearance underneath. Let us know how that works out!

I have immersion type heaters on the main engines which have their own thermostat so I leave them on almost all the time, except the hottest months in the South. Turn them off over night sometimes for cold start testing. They keeps the engines and ERs, and with the doors open, the lower level of the boat, nice and dry and toasty.

 

[Genesis]

Diver, be careful with the larger ones. I tried that route and discovered it was not installable due to the raised "Detroit Diesel" logo on the bottom of the oil pan. That's what drove me to the pair of smaller, 250W ones - and the ability to mount one on the SIDE of the pan and remain within the 6" clearance restriction.

 

[lumina]

Hi All,

We had the same issue Genesis describes with the logo on the pans bottom and ended up solving the problem the same way. We exchanged a pair of 500 watt heaters for a pair of 250's, which install easily on the side of the oil pan.

 

[Jackman]

We installed the 250watt wolverine pads on our little cummins 330b's. They made a tremendous difference...For example...This past weekend my dad and I stayed on the boat because we fished both days. The first day they started up within the 1st crank and absolutely no smoke and it was below freezing at the dock. During that night we had to shut off the pan heaters, battery charger ect because our electric heat kept tripping the breaker. Needed the heat because it was below 32 degrees at the dock. Next morning I smoked everyone out at the dock. No question that they work well.

Anyone know where to get parts for my ac/heater?

 

[Diver Down]

I'll follow your advice Genesis. Even going to the smaller pad, finding an accessible area is going to be tough. You mentioned installing one on the oil cooler. Are you referrring to the large (about 30" L x 16" diameter) cannister some of us have mounted on bulkheads?

 

[Genesis]

No. The oil cooler is on the side of the engine down low (inboard side of the port engine on a 6V92); it will accept a 250W Wolverine. The oil pan will typically accept a 250W heater on the side, again down low (but on the side, not the bottom.)

Make sure you sand to remove all paint down to bright, clean metal; you need 100% contact or the pad WILL burn up as soon as you apply power to it.

 

[whaler23]

Has anyone seen or ever used one of these magnetic block heaters?

http://www.sportsimportsltd.com/300-watt-magnetic-block-heater.html

 

[Genesis]

I'd be afraid it could fall off (I know, I know, it's a powerful magnet) and wind up setting something on fire.

Not much of a risk on a concrete driveway. Bigger issue on a boat.

 

[REBrueckner]

PS: nothing wrong with a pair of electric space heaters with thermostate control built right in especially pointed at each engine...about 750 watts on a low setting...it will heat more engine room air initially but then that air will warm the engine anyway and its a "throwaway" if anything goes wrong...but a direct contact heater being discussed here will likely do a faster job initialy given an indentical power to a space heater. A space heater with an automatic shut off if tipped over is a good safety feature....

When I ran my Webasto diesel heater in cold weather it kept the engine room warm enough I didn't usually need my block heaters...

 

[Genesis]

Only if you have a diesel boat! Those space heaters (even the oil-filled ones) are NOT ignition-protected and on a gas-powered vessel....

 

[Akyla]

I have used both the wolverine and the space heater approach. Wolverine wins by a long ways. Much better at heating the engines than any space heater can be. The draw is much less and the heat is directly where you want it to be. Plus they cant get knocked over by a wake or other incident and cause a problem that way. Many boat fires have occured due to use of space heaters.

Side benefit of heating the engines is that it keeps the condensation from forming on the engines due to humidity changes and this helps eliminate the rust issues. I never got that from using a space heater.