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Engine/Transmission (1994 - 1998) Block heater thermostat?

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Engine/Transmission (1998.5 - 2002) new thermostat time??

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BigPapa

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Does the block heater have a thermostat? How long does it take to heat up the engine that's been sitting all night at, say, 20*?



I know I can get a timer to put it on but I'm trying to decide when to make it come on to warm it up in the AM. I can plug it in about 25-30 minutes before I need to leave. Is that long enough to help?



Basically,will it use less electricity if I plug it up with a warm engine when I get home at 7PM and leave it on all night or if I plug it up or turn it on and let it warm up a cold engine in the morning?



Thanks,

Scott
 
No thermostat. It is just on when it is plugged in. I have mine on a timer that comes on about 3 hours before I leave for work. It's not that warm, but it helps it crank easier and warm up faster.

Half an hour probably won't help a lot if it is really cold there.



Randy
 
I leave my heater plugged in from when I arrive home till I leave in the morning. I use it from 30 degrees and less. I plugged it in the other day and did not hear the usual sizzle sound I normally get within a few minutes of plugging it in. So I unscrewed the power cord and it was kinda funky so I cleaned it and plugged it in again and still no sizzle. I left it plugged in and checked for warmth in the morning. NOTHING ! I know the cable has continuity in all three connections but I don't know if it is making good connection. I'm looking for the part number for the cord as well as the heater. Engine is a 2001 5. 9. Do any of you know either part number ? I've looked at other forums but can't find any help.
 
... . request the Fleetguard part #251919 from your Cummins shop..... it was $16 and change here in Maryland,with a club discount i got it for $12. 85:)

..... good luck,and don't forget to fill the plug holes with dielectric grease!!!! tom;)
 
FLG p/n 251919 is the cord only. If you buy FLG p/n 3928341 you get heater and cord. You can buy the heater only under Cummins p/n 3975628 ( old # 3940911)Shadrach
 
Half an hour won't do much. There is a lot of thermal mass in the engine so it take 2-3 hours. Plugging in overnight is a huge waste of energy. If you are in a place that is cold enough that you need to use the block heater regularly, I recommend running synthetic oil, and only using the heater for 2-3 hours. Much more time than this and you are wasting both money and energy.
 
... . when i know the temps are falling,i plug the truck in as soon as i get home... . 11pm or so... . and it stays plugged in until i'm ready to roll again... not sure of the exact current draw,but at least i'm sure the truck/engine are ready to roll when i am... ... ... . tom
 
Half an hour won't do much. There is a lot of thermal mass in the engine so it take 2-3 hours. Plugging in overnight is a huge waste of energy. If you are in a place that is cold enough that you need to use the block heater regularly, I recommend running synthetic oil, and only using the heater for 2-3 hours. Much more time than this and you are wasting both money and energy.



I did some crude experimenting with this and settled on 3-4 hours before I leave for work. So the timer comes on at 4 and I leave at 7. Less than 3 hours and the truck acted like it wasn't plugged in, but beyond 3 hours seemed to have only marginal improvements (heat in the cab slightly quicker). Either way, the money spent has got to be better than the exessive idle/warm up without plugging in. The first winter with my truck I was new to the whole diesel thing and it sounded like a locomotive and smoked like one too until she got going:-laf (neighbors loved that I'm sure). I plug in now as soon as temps go near freezing and the truck starts and goes just like a summer day. This winter I am running synthetic so we'll see how that effects the process.
 
I usually set my timer for anywhere from 2-4 hours before I leave. This depends upon the temp. When it's 30 I will go for 2 hours, but when it gets down around 0 or lower I will geo for 4 hours. I have toyed with the idea of instlling a timer and then a temperature sensor so it would not come on above a certain temp.



As for the block heater at the Deere dealer I belive they ran about $35-$50 for the heater and the cord. Just make sure when you replace it that the coil is not touching the block at all. It will instantly short out and you get to do it over again. Don't be scared they are not hard just watchout.



Does anybody have any experiance with oil pan heaters? I have thought about putting one on my truck to help with the oil temp as it is not ready for a oil change as of yet.
 
Huge difference whether or not i plug mine in. We've had a few nights at 8 degrees F. Truck would not start without being plugged in. I've been considering an oil pan heater. More interested in keeping my fuel from freezing, especially with B100.

Just installed a 200 Watt 20 amp fuel filter heater jacket. Wasn't doing much at first so i tried it with some different wires. Turns out i had bad wires and this thing gets hot to the touch in a few seconds. Perfect fit on the fuel filter, only thing is that it doesn't come with a way to keep it from sliding off. Bought it from dinofuelalternatives.com. I'll next be looking for an inline electric fuel heater and a frame mounted filter.
 
I use two 175 watt oil pan heaters, one 50 watt transmission pan heater and a 20 watt under each battery. They work pretty well when used. I don't plug in until 0. My trucks have never had an issue starting with the exception of bad batteries once and needing to adjust idle speed on the 12 valve once also. Synthetic was nice when I used it but the old truck drank it like water so I went back to dino juice.
 
I have toyed with the idea of instlling a timer and then a temperature sensor so it would not come on above a certain temp.



You can get a block heater cord with a temp sensor. It is over $100, though. The one I got was ~$90 at Peterbilt, without the sensor.



We have Zerostart block heaters. That is who makes the other cord.



http://www.zerostart.com/Files/us_zerostart_04cat.pdf (pg #77)



ENGINE IMMERSION HEATER LED INDICATOR LIGHT SYSTEM is what I have. I have the 3600049 kit (no sensor).



Works great, and if there isn't any juice to the cord, the lights are out. Nice to have if you have a GFCI outlet and it is tripped. Saved my butt a few times. :cool:
 
Does the block heater have a thermostat? How long does it take to heat up the engine that's been sitting all night at, say, 20*?



I know I can get a timer to put it on but I'm trying to decide when to make it come on to warm it up in the AM. I can plug it in about 25-30 minutes before I need to leave. Is that long enough to help?



Basically,will it use less electricity if I plug it up with a warm engine when I get home at 7PM and leave it on all night or if I plug it up or turn it on and let it warm up a cold engine in the morning?



Thanks,

Scott



Scott,



The block heater on my 1995 truck drew 7 amps when I checked it a few minutes ago. That's about 800 watts, which is about twice as much as I expected to see. The current draw may taper off as it heats up; I didn't measure it for that long. Since it doesn't have a thermostat, the longer it's plugged in, the more electricity it uses. For every hour and fifteen minutes that it's plugged in you'll use one kilowatt-hour of electricity (at my measured current). I don't know your electric rate, but it should be on your bill.



The practical advice from earlier posters about how long to leave it on makes sense to me. I think the Dodge manual said to plug it in two hours before you intended to start the engine.



Maybe I've been lucky with my two trucks, but they would always start in 20* weather even if they had not been plugged in. I would leave them at the airport parking lot, and had to take my best shot when I got home. They never failed me. (I hope I haven't jinxed myself now. ) I do use good batteries (Optimas) and take good care of them.



Good luck,

Loren
 
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