Where to ground a wrap style fuel filter heater

[fields_mj]

I'm adding a 100 watt wrap style heater to my fuel filter to aid in burining WVO blends, and I've got a couple of questions. FWIW I'm doing this on a '93 NA that's stock everything.

First, I'm planning on powering it from the Key On terminal on my GP controller. Should this cause me any problems? I figure the heater is going to draw between 8 and 9 amps, and I'm wanting to make sure that I'm not going to damage the controller by putting this load on it for extended periods of time. I'm thinking it will be okay, but I don't really have a lot of experience to base that opinion on.

Second, where should I ground the heater? I'm considering grounding it directly to the steel bracket that the factory fuel filter houseing is bolted to. I'm thinking that the bracket is a LOT heavier than the various grounding lugs that I see the batteries connected too, so it should be fine, but again my experience is pretty thin.

Thanks!
Mark

 

[icanfixall]

As close as the battery is to the filter my thoughts are directly to the battery ground.

 

[fields_mj]

I thought about that as well. I've got the stock battery cables, so I don't have any extra bolts, studs, or terminals that I can connect it to, but I could crimp a ring terminal on the wire and slide that under the nut on the battery clamp. I'm just nervious about taking that clamp off. I"ve had bad luck with them. Seems like every time I have to disconnect a battery terminal somewhere, something cracks, breaks, or falls appart. I'll make sure to pick up an extra battery clamp at lunch just in case. It will be a good $5 insurance policy....

 

[dgr]

I would put a relay in and use the GP power as a signal for the relay. Can you run your wire to the other end of the battery ground cable? There should be a bolt there you can put a ring on. That's how all the positive wires seems to be done on mine. Ring terminal to the hot side of the starter relay or GP relay.

 

[fields_mj]

I would put a relay in and use the GP power as a signal for the relay. Can you run your wire to the other end of the battery ground cable? There should be a bolt there you can put a ring on. That's how all the positive wires seems to be done on mine. Ring terminal to the hot side of the starter relay or GP relay.

That would be option 2. I guess I'm asking if I really NEED the relay? Seems to me that the relay is just one more component that I have to wire, find a place to mount, and that can fail when I really need it. If there's a good reason for it, then I don't mind going through the PITA to install it, but if it's not needed they why bother with the effort? The GP controller handles a LOT more than 8~9 amps, but it only does so for short periods of time (15sec or less). Still, it's been my experience that if a relay will handle the initial surge upon closure, then it will most likely handle the load indefinately. Then again, my experience is limited to machine controls on industrial equipment. I have virtually no experience working with the on board electronics on any vehicle.

I've got one battery ground up above the driver's side headlight, and the other is down under the Alt and water pump. It's basically covered with several years of dirt and oil, and I suspect that it's got a fair amount of rust on it as well. I'm not sure if I can get to it from under the truck which I hate doing anyway. Even with glasses and a face shield, I still end up with dirt in my eyes. From the top, I'd have to pull the grill and radiator to get to it. Been there, done that. So long as the water pump holds, I won't be doing it again. It would be faster for me to strip the battery clamp off the current ground cable, and replace it. Been there and done that too. Sucks, but doable.

 

[crewchief219]

I have no extensive knowledge but the ignition wire for the glow plug relay doesn't handle a large load for any length if time, it only acts to turn the relay on the controller on and off. Putting a draw on old wires could cause them to overheat as well. I just had to bypass my power wires for my glow plug controller just because they were old and couldn't handle the 10-15 seconds of power being drawn. Like I said, not an expert, but I just saw what can happen to old wires with the amount of power they were designed to carry fail and burn a harness.

 

[crewchief219]

If you want to avoid a relay as a point of possible failure I would run a new power wire from somewhere else. Maybe even a fuse and switch in cab.

 

[fields_mj]

I have no extensive knowledge but the ignition wire for the glow plug relay doesn't handle a large load for any length if time, it only acts to turn the relay on the controller on and off. Putting a draw on old wires could cause them to overheat as well. I just had to bypass my power wires for my glow plug controller just because they were old and couldn't handle the 10-15 seconds of power being drawn. Like I said, not an expert, but I just saw what can happen to old wires with the amount of power they were designed to carry fail and burn a harness.

That's exactly what I'm afraid of. I already have a line running from the key on at the GP controller to an on/off switch in the cab, then back out to the engine compartment. It's 12 .ga to the switch then 14 out to the engine compartment. It's coiled up right now and I'm trying to decide whether to drive a relay with it or go straight to the heater.

Can anyone recommend a god relay that I should be able to find at any local parts store?

 

[fields_mj]

Well, I have to admit, I was making a LOT to do about absolutely nothing. I installed a 30 amp relay over on the pass side fender, and it was easy as pie. The relay was a Dorman that I picked up at Orielly's on my way home for $7. It had the 4 blade connections on it, and it had the wiring pattern molded into the oppisite side along with a single tab with a hole in it for mounting. Very easy. Of course I couldn't finish installing the heater because it's about 2" too short to reach all the way around my fuel filter.... Grrr... Oh well, I"ll pick up some velcro from wally world to make it a little longer and then it should be good to go. The hardest part so far has definatly been installing and wiring the switch in the dash. I have to be doing something wrong. There has to be an easier way to do it than spending 2 hours laying on my back under the steering wheel fishing wires, trying to find a place to drill a hole for mounting, and then trying to feed those wires through that hole. And forget about screwing any kind of nut on anything to hold it all togethere....

 

[crewchief219]

My trucks previous owner ran wires through the steering column and installed a switch on the plastic under the dash, by your right knee. No idea hold long ago it was installed but it seems to have held up.