Grid heaters

[NSperduto]

I know dodges run grid heaters instead of glow plugs, but just what does a grid heater do?



Also, I was discussing a fuel gelling issue and additives with someone and I was told that cummins pre-warms their fuel. Is this true?

Actually here's what I was told.



DC does not recommend fuel additives for diesels. I asked our department inspector who has two Cummins, has a 98 and 03 and he says either your buddies truck was not running on winter fuel mix or his fuel heater system failed. Cummins pre-warms the fuel and if he is positive he was on winter fuel, his fuel heater is bad. That has to be it. Last winter when his 03 was new, it was in the single digits for weeks here and he had it outside plugged in and no problems. He said the additive causes it to wax up and that is not good, that is why there is a fuel heater. The older Cummins might have to use it

 

[lmills]

I am not sure about your buddies situation, but it sounds as though he may have had some fuel gelling. Maybe ha=e got a batch of fuel that wasn't winterized.



As for the grid heaters, they look like a toaster element. They are located below the intake horn. As air is drawn through them it is heated.

 

[Vaughn MacKenzie]

Yes the fuel filter housing has a heating element to warm fuel. In normal operation fuel circulates through the element and the injection system and some always circulates back to the tank to warm the fuel there.



The heater only comes on below a certain temperature (not sure what). There is natural heating of the fuel by normal operation too, so eventually the heater will turn off as you drive when the fuel warms up.



It doesn't do anything to warm you fuel when your truck is shut down though so if it's parked outside in cold weather then yes, add additive.



I disagree with the No Additives thing, I've used it extensively summer and winter and positives outweigh the negatives (smoother operation, cleaner injection system, improved MPG).



Vaughn

 

[Dean Upson]

My 86 Ford had a fuel heater that died and a related fuel gelling problem.



Dean

 

[rbattelle]

To expand on what Vaughn said, the grid heaters increase the cylinder charge temperature. That, in turn, increases the rate of fuel evaporation upon injection, which decreases ignition lag and rate of pressure rise. Translation: less smoke and quieter operation.