Ok, so if you did not read my other post on alternater help , I am in the proces of droping a 93 cummins into my 70 chevy truck. I now need help with
the grid heater. I have wired the cold start solinoid through the original intake temp sensor, can I wire the fuel heater through the same senser, but useing a relay so not to over load the circit. and how about the grid heater, can I use the same triger ? or should I use a toggle switch for this? how long does it normaly stay on for? how long is to long? also does any one have pics on how to wire it, there are 4 terminals on it, it looks like two for each coil. I only have a factory ground on one of them . Do i ground the other and run power to the other two terminals , or do I wire them in serise? are both coils normaly used ? You can see my confusion here. I dont want to burn it up ,I am sure it aint cheap!

 

Any body??? please?? help???

 

Most people don't care for my comments. But, how cold does it get where you live? If not much below -10*F, I wouldn't worry about. Things needed to be in good shape for good cold weather starting: Big battery- group 31 w/big CCA, alternator, starter, and air tight fuel system. Grid heaters IMO just drain on the first three things there. Especially after the engine is started. Mine are unplugged. Don't have any cold weather starting issues. Grid heaters and short trips, say to and from work are a bad combination. They'll cycle all the way to and from work, never giving your battery a chance to recharge. Over a period of time or just the next morning when its COLD out, you'll have a weak battery and it won't get the job done, that last 15 secs of grid heat will wipe out any chance or it starting. Then again its just me and thats my opinion.

 

I agree with Bill, the only real function of the grid heaters is for emissions reasons, not a starting aid.

I prurposelly don't let mine run when it is down around 0 degrees, they sap to much power from the battery that I need to crank the engine over. At that temp a battery is sapped down in output pretty bad.

I don't have my FSM here with me, but could look later for a wiring diagram if nobody has one handy.

 

Yea ther are some mornings that it is below zero, I drive 50mi one way to work so it should have plenty of time to charge, what do you think about optima batterys? also is it about a 15 second cycle on the grid heaters?

 

optima is to small, unless you buy two of them and run in parallel. That gets expensive. I like the interstate workhorse batteries and is what I use.

I plug my block heater in while at home. Have a timer that turns it on for two hours before I leave for work. Grid heaters don't even turn on when I do that.

The length of the cycle varies by the outdoor temperature on the grids. I don't think mine ever run longer than about 10 seconds or so.

We have some farm equpment with the cummins in them, they never had grid heaters.

 

So if I run it to a toggle or button, through a relay of corse, and gave it a little stab on cold mornings its kind of hit or miss weather it realy helps for the cold start?How about the fuel heater ? could I wire it from the cold start solinoid or willl that make it run to long. If I do hook up the grid heater, do I wire both coils , just one or in serise?
Thanks

 

As far as starting, to me it makes no difference if the grid runs or not. The EPA had dodge put them on to lower the amount of white smoke out the tail pipe you get until the engine warms up. Like I said when the temp is getting down below 10deg F I don't run mine because they pull alot of power off the bat.

If you want to run them manally though I don't think there would be any problems with 8-10 seconds to them. The factory PCU runs them on a cycle for several minutes after the engine is started as well (once again for emmissions reasons).

 

Cool, thanks for the info, anyone have any info on the fuel heater, is it needed, and if so can I wire it off the cold start solinoid?

 

I would keep the fuel heater. It has it's own thermostat built in, so just wire it to something that's hot with the key on. It pulls about 5 amps.

If this Chevy is an ex-diesel, you could use the Chevy glow plug controller to run the relays for the grid heaters. Just put a thermal switch in the power to the control side of the relays so you don't have the grids kicking on in the summer.

The grids are run in paralell. Two relays, two heavy gauge (6 AWG I think) cables to the grids, and then a common ground to the engine.

 

As I recall, the two grids do NOT run in paralell, but cycle independantly depending upon the temperature registered by the sensor inside the intake manifold. The Chevy controller would NOT work with the grid heaters properly. You could run them on normally open switches (though you would need relays) and choose the cycle time manually. I think that they help the starting a little in very cold temperatures. What is annoying is that they ycle after the engine is running -- this is totally un-necessary for a direct injection engine, and is a killer on the batter at night with the headlights and defroster on.

 

From a former GM dealer tech., the glow plug controller from a 6.2 or 6.5 won't run the cummins grids right for sure. Glow plugs draw way less amperage than the dodge cummins grid setup and heat quicker than the old toaster oven.

UPS trucks have cummins in them right? I'm sure those types of trucks would have a compatable controller.

 

having the same issue with my fuel heater, never really cared for the grid heaters those got disconnected even when it had the ecm. But the fuel heater DOES have it's own built in thermostat? I thought it did, seeing as it has only 2 wires, but really didn't need to burn my truck to the ground lol. Anyone sell the new heaters? Or rebuild kits? just to be certain ? It's been about 3 years since mines seen any electricity. Guess that Ign Coil wire will come in handy after all in the painless harness lol. Knew there was a reason I left it in there.

 

That's why I said to use it to run the relays for the grids. It's less than ideal, but it would be easy to do and would't require any thinking from the operator.

 

Wannadiesel, Setting up a system like this with incompatable components could be disasterous (melted grid metal falling into intake manifold!). GM's glow plugs are the "fast start" type except for the old 4.3 V6/ 5.7 V8 and the 6.2 in 82 and 83. Those early controllers might cycle the cummins grids long enough to generate adequate heat but, they were terribly designed and numerous service bulletins recommend updating to the fast start system. Your intentions are good but the GM controller will not cycle the cummins grid heater for long enough to heat it adequately. GM had relays on all the fast start systems.

Again, some UPS/step van type trucks used cummins 3.9/5.9. I would bet they have grid heaters and some sort of stand alone controller that is designed to work with the cummins grid system.

Theres always the toggle switch to run grid relays method as well, just as long as a guy knows how long to run them for the outside air temp. That method is the most cost effective.

Also, in 1970 there was a rare diesel engine option in GM pickups, 3-53 detroit diesels were factory optioned in a very few trucks, little information is available as they are extremely rare. Some parts (if you can find them) might be utilized in the swap. I doubt there was a cold start aid though besides either injection!

Best of luck with the swap skchevota!