[97_73stroker]

Hey all at the place where i work we have a 99 F550 that is having a hard time starting when its really cold out(0-20*F). I know its not what it's intended for but i was woundering if i could take and run a jumper wire from the ground terminal of the GPR to the ground terminal of the air intake heater relay so they both come on. Just curious tell me what you think.

 

[tbpower]

The air intake heater in cold temps is designed to come on only when the glow plugs are off. If they are both on this is going to draw more on your batteries when you start it. I would look at the hard start sticky and see if you are having a problem with your glow plug system. If you are getting the romps when starting you might want to consider switching to a 5w/40 synthetic that is approved for your truck.

See this site for other conditions when the air intake heater will activate: Air Intake Heater Plug

 

[Phanderson]

Hey all at the place where i work we have a 99 F550 that is having a hard time starting when its really cold out(0-20*F). I know its not what it's intended for but i was woundering if i could take and run a jumper wire from the ground terminal of the GPR to the ground terminal of the air intake heater relay so they both come on. Just curious tell me what you think.

I have been thinking the same thing and I just came across your post and was wondering if you had tried this. I was thinking that it would help because it’s going to warm up the air some before going to the glow plugs and should work similar to the dodge grid heater please let me know if you have tried this. My email is [email protected] and for subject please put intake air heater

 

[klhansen]

What tbpower said. You'd draw power from the starter and slow it down. The glow plugs by themselves draw over 100A when the relay is activated. I haven't measured the draw on the Intake Air heater, but I'd imagine it's pretty high as well.

I'd guess that you have one or more glow plugs that have gone bad. There's a link in my signature for the thread he mentioned.

 

[DENNY]

I agree with what the other guys have said. I would expect more starting issues if you tried running the intake heater with the glow plugs. Recheck the glow plug relay, glow plugs, and alternator output. If all are good I would expect a starter going bad. How fast is the motor spinning over when you try to start?
DENNY

 

[Phanderson]

What tbpower said. You'd draw power from the starter and slow it down. The glow plugs by themselves draw over 100A when the relay is activated. I haven't measured the draw on the Intake Air heater, but I'd imagine it's pretty high as well.

I'd guess that you have one or more glow plugs that have gone bad. There's a link in my signature for the thread he mentioned.

I know my glow plugs are good I change them out every other year if they need them or not because of where I live and hunt one to two weeks out of the winter our daily high can be from -5 to -10 degrees Fahrenheit and our nightly lows during those few weeks can be anywhere from -25 to -40 below zero and one year where I hunted the night temp hit a -55 degrees Fahrenheit below zero. And where I hunt I don't have a generator to plug it in. I run 0W40 Amsoil with Lucas oil stabilizer. The starter spins a little slower when it's that cold but not much. I am just trying to figure out a way to help preheat the air before it goes into the cylinders and I was thinking of the air intake heater because I hate having to cycle my glow plugs 6-8 times when it's that cold out. That is why I make sure my glow plugs get changed every other year is because I don't want them to fail and when I change them I change the glow plug wire harness too. I also have two fuel heaters on it besides the factory one to help preheat the fuel before it get injected. Any ideas would be great

 

[DENNY]

OK we got two guys posting on the same issue I will try to cover it all at once. Your glow plug will stay on much longer than the glow plug light shows, even after the engine has started they are temp controlled by the ambient temp. The glow plug light has no relation to how long they are on. You can run a wire from the glow plug side of the solenoid to a small led in the cab to see when it is on. If the fuel heatesr are electric I would wire them so they are off when starting/on when running. They will just be another power drain. Warm fuel will prevent jelling a good thing to have at that temp but I don't think it will help starting. Once you get into the high mileage starting a 7.3 cold soaked (over 24 hours) at -20 and below can be hit and miss. Klhasen and I have both had the slow starter when cold issue and replacing them solved the problem. Mine even checked out fine when I took it to NAPA. I have started my truck after being cold soaked at -20, it started but was not happy for the first few min. The slow turning engine will have problems creating heat as it compresses the air in the cylinder. The faster the spin the more heat the better the start. That is why we are not recommending more current drain on the battery. If you are going to leave a high mileage truck out in below -20 for extended periods you need to find a power source/ invest in a generator / pull the batteries and keep them warm. Remember part of the issue is batteries loose a lot of power when cold, that adds to the issues.
DENNY

 

[Phanderson]

If you want to get kinda technical it is proven that warmer the fuel easier it is to start because the fuel is better atomized so it has more surface contact with the air so it ignites better because you don't have large fuel drops even in gas cars from carburetors to fuel injection

 

[Phanderson]

OK we got two guys posting on the same issue I will try to cover it all at once. Your glow plug will stay on much longer than the glow plug light shows, even after the engine has started they are temp controlled by the ambient temp. The glow plug light has no relation to how long they are on. You can run a wire from the glow plug side of the solenoid to a small led in the cab to see when it is on. If the fuel heatesr are electric I would wire them so they are off when starting/on when running. They will just be another power drain. Warm fuel will prevent jelling a good thing to have at that temp but I don't think it will help starting. Once you get into the high mileage starting a 7.3 cold soaked (over 24 hours) at -20 and below can be hit and miss. Klhasen and I have both had the slow starter when cold issue and replacing them solved the problem. Mine even checked out fine when I took it to NAPA. I have started my truck after being cold soaked at -20, it started but was not happy for the first few min. The slow turning engine will have problems creating heat as it compresses the air in the cylinder. The faster the spin the more heat the better the start. That is why we are not recommending more current drain on the battery. If you are going to leave a high mileage truck out in below -20 for extended periods you need to find a power source/ invest in a generator / pull the batteries and keep them warm. Remember part of the issue is batteries loose a lot of power when cold, that adds to the issues.
DENNY

I know the glow plugs stay on longer than the light. In fact mine will stay on two full minuets no matter what the ambient temperature is and the Ford dealership I talked to about this and the diesel repair shops around where I live said that is correct it for 2001 Powerstroke

 

[ArcticDriver]

Just because we are getting kinda technical, like Denny said, the GP system can stay on for as long as 120 seconds. If yours always cycles for that length of time (even when warm) then it is not working as designed. It will shorten the life of the GPs but probably not an issue with 2-year change-outs. Do you change out the GPR every 2-years as well?

At those temps you mention, and I work in those temps, I have to wonder what you are hunting for...caribou? haha.

What power source do your auxiliary fuel heaters use? Seems they would be 120v or they would draw too much 12v when parked? If I was parked at a hunting cabin or a trailhead in those temps, a small auxiliary gasoline generator could be the difference between life & death in an emergency evac.

 

[ArcticDriver]

Diesel fuel inlet temperature.
Interesting topic was mentioned above concerning benefits of fuel vaporization/combustion (at start-up) by increasing fuel temperature but there is also a point of diminishing returns (once started) for power output as a result of the simultaneous decrease in diesel fuel density with increasing temperature.

Welcome to the forum Mr. Phanderson. Typically, when we discuss cold temperature concerns here on the forum, the number one issue is the risk of fuel gelling but it would be interesting if you could elaborate on the topic of heating diesel fuel and also your choice of auxiliary tank heaters. Thanks.

 

[klhansen]

Glow plug on-time is mainly dependent on OIL TEMPERATURE, not air temperature.
From the service manual:
On-time normally varies between 1 and 120 seconds. With colder oil temperatures and lower barometric pressures, the plugs are on longer. If battery voltage is abnormally high, the duty cycle is shortened to extend plug life. (The glow plug relay will only cycle on and off repeatedly when there is a system high voltage condition greater than 16 volts.)

 

[DENNY]

Panderson
You are correct! However the fuel your are using to start the engine with is in the heads already. None of the three heaters will warm it. Now if you plug in a generator everything will be warm. As the starters start to fail they draw more current to the point that the injectors will not fire, that is why we recommend not increasing draw on cold batteries. It is a free world I would think all you would need is a jumper wire from the Glow plug solenoid to the Air Intake Heater Solenoid to make them both come on at the same time. Go find yourself some of that -20 weather and let us know how it works.
DENNY

 

[Phanderson]

Just because we are getting kinda technical, like Denny said, the GP system can stay on for as long as 120 seconds. If yours always cycles for that length of time (even when warm) then it is not working as designed. It will shorten the life of the GPs but probably not an issue with 2-year change-outs. Do you change out the GPR every 2-years as well?

At those temps you mention, and I work in those temps, I have to wonder what you are hunting for...caribou? haha.

What power source do your auxiliary fuel heaters use? Seems they would be 120v or they would draw too much 12v when parked? If I was parked at a hunting cabin or a trailhead in those temps, a small auxiliary gasoline generator could be the difference between life & death in an emergency evac.

I change out the all glow plug related items I was originally using a gas generator but someone went ahead and stole it and I am not going to put out money for a person still another generator. I guess the best thing to do is go with a hydronic s3 system where it uses some fuel and a little battery power to heat the engine and cab all at one time like they use on class 8 trucks

 

[klhansen]

I guess the best thing to do is go with a hydronic s3 system where it uses some fuel and a little battery power to heat the engine and cab all at one time like they use on class 8 trucks

While those are cool things to have, you could buy two generators for the cost of either a Hydronic S3 or Webasto heater. I personally would rather have a generator. That's way more versatile. And a chain and lock at least slows down the thieves.

 

[Phanderson]

While those are cool things to have, you could buy two generators for the cost of either a Hydronic S3 or Webasto heater. I personally would rather have a generator. That's way more versatile.

But when you have people that steel them from the back of your pickup even when they are bolted down how many do you put in before you look for a different option with me one is too many

 

[klhansen]

I understand. Have you thought about an autostart with a timer function? Even in the coldest weather, if the engine is up to temp, it takes a long time to cool back down. If it's been less than 8 hours, you shouldn't have any trouble starting without being plugged in.

 

[Phanderson]

I understand. Have you thought about an autostart with a timer function? Even in the coldest weather, if the engine is up to temp, it takes a long time to cool back down. If it's been less than 8 hours, you shouldn't have any trouble starting without being plugged in.

I have but when I go hunting I am away from the vehicle for 10-18 days at a time

 

[ArcticDriver]

I change out the all glow plug related items I was originally using a gas generator but someone went ahead and stole it and I am not going to put out money for a person still another generator.

I hate that concern. I actually bought a beat-up gasoline powered truck to leave at trailheads because of vehicle break-ins and thefts....and cold winter starts.

 

[klhansen]

I have but when I go hunting I am away from the vehicle for 10-18 days at a time

So if you set it to start and run for 30 minutes once a day, it would start when you got back to it.
I once started my truck at 6F when the block heater cord was broken and the GPR was inoperative. Granted it took about 20 minutes of intermittent cranking, but it did start. I'm contending that if your batteries and GP system are in good shape, it should still start after cold soaking for that long without assistance.
Another alternative: A jumper battery (stored in the cab to prevent theft), separate from the vehicle batteries could be used to power the glow plugs till it was empty, and you'd still have the full capacity of the starting batteries for cranking. Just clamp the jumper to the output terminal of the glow plug relay and leave it there and go have a smoke (or whatever).