I've been putting this off for some time now but it really needs to be repaired.
The intake heater quit working on my 92 CTD. I can hear the relays clunking. I get voltage to the relays on the large supply lines and at both of the smaller leads.
No voltage is coming out of the relays. No voltage at the heater.
Yeah, I checked for current while the relays should have been functioning.
If it drops into the low 60s, I've got to plug the truck in to prevent the spitting, smoking, and choking of a cold diesel.

Any suggestions?

 

Sounds like the relays are dead, then. If it's any comfort to you, mine are dead and the truck started just fine all last winter, as cold as 17 degrees unplugged. Ran lumpy for about the time it takes to build oil pressure, then smoothed out and drove fine. There is a little bit of white smoke, but they run fine without the grids. When it's plugged in it fires up like it's summertime.

 

Mine work, but unless the temps are below 30 deg or so I never even bother to wait for them. I'm too impatient. Truck starts on the first stroke and runs fine with just a hint of white smoke.
Jay

 

Hi all,I am new to the site and to diesel power as of this summer.Ihave a 92 CDT 350 that came from the north west of the US.when new and ended up in AZ. when I got it which brings me to my question.Do all Cummins engines have a heater from the factory or is this something that has to be added and if so where does it mount on the engine?This morning it was 15 degrees and the truck started fine as I could hear the (intake) heater cycle on and off.I noticed that there is some white smoke but I didn't think about it because my 440cu.will fill the yard with it on a cool day.Does it mean anything important? Thanks for any input.

 

Welcome. All Cummins in Dodges have the intake heaters. In very cold weather you will still get some white smoke even if the heaters are working properly. This is unburned fuel because of cold temps in the cylinders, not condensation like a gasser makes. If you continue to have white smoke after the engine is up to temp you have a problem, but it sounds like yours is OK.

 

My truck doesn't like the cold!
This morning, temps were in the 50s and I didn't have it plugged in. The truck fired up quickly but shook the whole truck something bordering on violent and belched enough white smoke to float across the street. When I touched the gas, everything got worse.
After it had run for a minute or so, heat built up in the motor and it purred like a kitten. Same old happy self.

 

My truck does the same thing feets...

Pretty much anything below 60 degrees and it'll dump white smoke out the tailpipe for a minute or two. Usually I back the truck up the shed outback and point the 5" tailpipe at it...then watch the wasps flying out gasping for clean air.

Makes the "wait" alot more interesting for sure!

In really cold weather you can hear the clicking, and watch the amp gauge drop & rise...so I guess mine is working. I just wish it wouldn't smoke so much in the morning...oh well.

 

I thought that black smoke was unburned fuel, no??

 

Black smoke is unburned fuel that didn't burn because there was too much fuel. White smoke is unburned fuel that didn't burn because the cylinder was too cold.

 

how do you tell if the grid is working? If the voltage gauge is moving, i assume it is working?
Ryan

 

Yes, you'll see a large deflection in the volt meter each time the heaters cycle. If you have your headlights on, you'll see them dim as well. That mens they're working. When you exceed a forward speed a little over 15mph, the heaters will shut off until the next time you cycle the ignition.

 

Many times the reason for the shaking and bucking during cold weather start up is due to an idle setting that is too low.
If you bump up your idle to say 850'ish then when the heaters kick in you'll have enough idle RPM to keep the truck from being drawn down so far that it shakes like a wet dog...mine used to do the same thing till I tweaked the idle.

pastor bob...