Engine/Transmission (1994 - 1998) Block heater

[ebrooker]

Is there someway I can test to see if the element in my heater is bad or if it is just the power cord? Also where is the best place to get a new block heater if it has gone bad? If someone has replaced there's recently how much did it cost and how hard was it to do? Any help would be appreciated.



Thank again

Eric

 

[Desperado]

I'll bet that the cord is bad, it happens alot, replace the end plug it in with the hood open and listen you should hear what sounds like a water heater, little hiss.

 

[wsmalley]

Not trying to steal the thread or anything as this is on the subject of block heaters... .



What is the recommended temperature for plugging the heater in? It's starting to hit low temps in the 20's and this is my first diesel and just wanted to get some opinions. Thanks ya'll

 

[Desperado]

I plug mine in when it gets to the low 40's high 30's makes for a faster warm up and easer start, put it on an out side timer set to come on a couple of hours before you get up in the am no need to run it all night.

 

[wsmalley]

Thanks... . any ideas on where to find a timer? All I can ever find are the 2-prong ones for lights and such... never can find one for a polarized plug

 

[illflem]

I've seen under $20 timers at Home Depot with three prong. You can also use a 2 to 3 prong adaptor and connect the ground wire from the adaptor back to a ground such as a screw on your outlet. Not a good idea to run the heater without a ground, if anything messes up your whole truck could become hot.

 

[Dan_69GTX]

For the timer - I got mine at ACE hardware. Just make sure you get a timer that can handle the current for the heater - such as an appliance timer - you will fry a light timer.





As for checking the block heater - there are several things you can do. Use a VOM (volt ohm meter) check the resistance between the two spade terminals of the plug. If you have a LOT of resistance you have a bad element (very seldom does an element go bad this way). If you have infinite resistance (no connection at all) you then need to check between the plug and the block heater for each wire. If one of these is open, just replace the cord. If these are good, check the resistance of the block heater itself - if it is open - you must replace it.



Never replaced one in a cummins so I can't help you out there.



Dan

 

[CumminsPower98]

My heater went bad. I tested it and it would act strange. It would start out with less resistance and then build the longer I left the tester on there. It would top out at about 85 ohms. I bought a new one and tested it and it showed no resistance at all and it works great. I bought mine from Cummins. I don't know what year truck you have but mine is a '98 12v. '98 and up takes a different heater then '94-'97. Here are the part numbers for '98 with the newer block. Heater 3940911, cord 3923050



The older ones go in a freeze plug and the newer ones thread into a specially made port.



Mark

 

[Dan_69GTX]

Do you remember how much they were??



Thanks!

Dan

 

[Gifford]

Timer for Block heater

I found one at WalMart that was only 9. 00 It is rated for 15 amps and has 3 prong (grounded) in and out. It was hiding in amongst the regular lamp (2 prong) timers so you might have to dig around a little bit.

 

[CumminsPower98]

Heater was $23. 38 and the cord was $29. 59

 

[Midnite]

Originally posted by CumminsPower98

The older ones go in a freeze plug and the newer ones thread into a specially made port.

Does anyone know why this might be? My '92 has the freeze plug type, but if there are any significant advantages to having the threaded type, I might try to install one of those.



Thanks,

Mike