Engine/Transmission (1998.5 - 2002) Disconnected the Grid Heaters

[Vaughn MacKenzie]

Well I'm tired of the grid heaters coming on so often even when the engine is pretty well warmed up, so I decided to disconnect them. I unhooked one wire from each relay which goes to each grid.



I plan to wire in a double-pole switch so on cold mornings I can just flip it on and the ECM will take over normal operation. Once I get underway I'll flip it off. But for now my lazy rear is going to drive without grid heater assistance. Considering how quickly I get around to stuff and the way it's been warming up toward spring, I probably won't happen 'til I need to get ready for next winter.



It does smoke noticeably more in the morning but cleared up in less than half a mile once I started out. I usually take off within 30 seconds of firing up.



Vaughn

 

[TPlasek]

After making many short trips to here and there and a 15 mile return trip, I entered a fast food drive thru last night. I was behind three people. In a few minutes, my temp was to the low side of normal, and I heard the grid heaters start to cycle. They continued to cycle the entire time I was waiting to get my food. It was on in the low 40's outside. I was thinking my IAT sensor was reading bad, but now I hear this may be normal.



Can anyone confirm this??? I don't think in Houston we need them anyways. I too may disconnect them. Save the wear and tear on batteries and alternator.

 

[Vaughn MacKenzie]

Yes this is a common complaint, TPLasek. I thought about the IAT sensor but figured it would be a waste of $$.



I heard someone smoked their alternator 'cause they got into a situtation where they were stuck in traffic or something and the darned grid heaters kicked in so long it finally fried it.



This morning was a good test to see how it would start without them since it was quite a bit colder than it's been lately. It got down to 25F or so, but it's usually been in the 30s & 40s overnight in this part of Washington.



Vaughn

 

[Jvann]

This is probably a dumb question but here goes anyway. What is the actual purpose of the grid heater? I was under the impression that it was a starting aid to assist the engine start by warming the intake air. A friend of mine whose Cat engine almost caught on fire because of it insists the grid heater is an environmental gadget that keeps the engine from smoking when it is started cold. He took his off the Cat. I always use the block heater when temp is below freezing but I'm confused by the actual purpose of the grid heater. Thanks for any info!

 

[HVAC]

The Texas Tornado Says---

Run the trigger wire for the relays through a pressure switch that senses oil pressure. When the engine starts and pressure comes up the signal to the relays is interrupted. The heaters won't come on.

 

[RADdodge]

Great Idea HVAC...

That's a good idea HVAC. The only reason I disconnected the grid heater relays were because the battery was too low to start with the grid heaters turning on one morning. The thing wouldn't even turn over. Disconnected the heaters and it started about like normal. Some white smoke for a few seconds, but that was about the only difference I noticed. It's amazing how much juice those suckers pull. With the pressure switch, you would only get the heaters for the initial start if you wait for the "Wait to Start" light to go out.

 

[99guy]

I too quickly tired of the grid heaters cycling, wanted an alternative start assist and wanted to better know what they were doing. I wired a switch to lock out the grids, tied the grids to indicator lights in the cab and added a circuit for the either assist when the grids are locked out. Works good, wiring simple. Wiring would be same for grid lockout and just leave off the either if you’re not interested in that. It’s also a good way to troubleshoot a bad grid relay.



#ad

 

[JJW_ND]

They help below zero.

I ran with one grid (bad relay) and starting one morning with temps at -5 (truck setting outside for several days) It would not start until I hooked up the second.



Temps from 20 - zero they help. Above freezing I never wait to start.



jjw

ND

 

[99guy]

Originally posted by Jvann

This is probably a dumb question but here goes anyway. What is the actual purpose of the grid heater? I was under the impression that it was a starting aid to assist the engine start by warming the intake air. A friend of mine whose Cat engine almost caught on fire because of it insists the grid heater is an environmental gadget that keeps the engine from smoking when it is started cold. He took his off the Cat. I always use the block heater when temp is below freezing but I'm confused by the actual purpose of the grid heater. Thanks for any info!

I’m betting he’s on to something there. We’ve been starting diesels in the cold for a long, long time without grid heaters. I find that after starting below around 20 deg. F. flipping them on for a short while does “clean things up” till the engine builds some heat. I’m voting that it’s more of and environmentally friendly thing, at least to look that way anyhow. And after all, if that’s a concern, is a little smoke worse than using extra resources to build the grids, wiring, relays, extra batteries, bigger alternators, and the fuel to turn them in the end result?

 

[Vaughn MacKenzie]

I can see where starting without them in cold weather, making a lot of smoke, and repeating the process frequently without a good hard run would create a carbon buildup that wouldn't be good for rings, valves and injectors.



HVAC I like your idea, very good thinking. Gives a little assist when it's nice and cold but shuts right off once you get going.



If the temps got very cold I'd definitely hook it back up, but, it's hardly been any colder than 5-10F above 0 for many years. My biggest concern would be going into the mountains or traveling to a colder climate.



Vaughn

 

[Pit Bull]

I thought I had too much time on my hand You guys need to start working on world peace :-laf

 

[illflem]

Originally posted by Jvann

. What is the actual purpose of the grid heater?

Every diesel I've ever been around, even old ones, has some method of cold weather starting. Grid heaters are probably the best method I've seen, popping the hood and spraying either in the air cleaner probably the worst. Other methods are compression releases that open the valves so the engine can spin easily and build up heat. Glow plugs that tend to burn out. Block heaters that need a place to plug in. I've seen some older diesels that have spark plugs and start on gasoline till the engine warms then switch over to diesel.

 

[truckstom]

https://www.turbodieselregister.com...age=15&highlight=grid heater fix&pagenumber=2



check this out if y'all haven't seen it. It works GREAT.

For the auto guys, I had to get a 90 degree brass elbow, then put the pressure switch in it. grids come on before start-up... once started NO MORE GRID CYCLINGOo.





hope this helps



on edit: I believe this is the one HVAC is talkin' 'bout

 

[HVAC]

Yup, Dat's Him

That pressure switch trick was Dean's idea, alias "The Texas Tornado". Dean's the guy with the variable geometry "Tornado Turbo".



I wonder how many folks really need the grid heaters. I pulled them out of my "98 truck years ago. Unless you see sub freezing weather regularly... ... ... .....

 

[thendrex]

grid heaters

How do you know when they're on? Is it when I see my lights dimming for some unknown reason? I didn;t know they came on again after start up... .

 

[BFC]

Re: grid heaters

Originally posted by thendrex

How do you know when they're on? Is it when I see my lights dimming for some unknown reason? I didn;t know they came on again after start up... .

That be it!

 

[Diesel Freak]

Got mine disconnected from the ECM, and I use a momentary switch on the Dash to operate the relays.

 

[TURBOs4LIFE]

Smoke while pushing the go pedel I like Smoke at idel when cold I dont! So I think I'll live with my grid heaters!

 

[Pit Bull]

Have you guys thought about getting rid of that big plastic tank in the engine compartment that holds windshield washer fluid? Just think of all the room it takes and what we could put there??? I have come up with a modification, I carry a bottle of Windex in the cab and when the window gets dirty I just roll down the window and spray it. I am working on a tank for the bed that will hold 30 gallons of fluid and then I can run the hoses over the top of the cab and spray down on the windows instead of how DC did it (spraying up, bad design). I will add a special switch to activiate the new windshield washer spray source. Boy improveing on the OEM design is fun :-laf

 

[99guy]

wowee zowee, 30 gallon!?!?