Ok, Ive searched but not come up with some answers, so here goes with the 145th hard starting thread, sorry.

Above about 20 Deg, my new 97 will start just fine, cycling the grids twice and applying about 1/4 throttle. Below that, it is a real BEAR to get started ( not plugged in BTW ). Now, I know nothing about when the fuel filter was last changed, in fact, I just found the stupid thing ( will be asking a seperate question on the next thread! ), but it has good power, and I would tend to believe I would have a starting issue no matter the temp if it were marginal. I do get a longer Grid cycle time the colder it is outside, but I do not see any indication that the grids are cycling once the truck is running. I have run 2 tanks of Winterized through it, and am running PS winter additive, so I can eliminate fuel gelling. I have 2 brand new Mopar batteries, and the thing will crank for what seems like an hour without running them down. ( I know, 20 seconds on, 2 min off ) I am sure there is some pertinant information I am missing, so let me ask my questions and get rolling with the info.

1.) Realisticly, what temperature should this thing start at ( 97 12V, 100K miles, stock in every way that I know of )? I ask this because my 4BT ( with a VE pump though ) will start at 10 below without ANY aids. It doesnt like it, but even without grids, ether, plugged in, etc, it just pops off and settles in after 30 seconds or so. I would kind of believe the P7100 pumped 6BT should do the same thing.

2.) Along those lines, is the P7100 pumped truck harder to start in cold weather than the VE pumped trucks?

3.) Does the Fuel heater have anything at all to do with starting? From what I read, it appears to be more for anti-gelling than starting.

4.) After the truck starts, and the grids cycle, do they both cycle like when you start it, or perhaps do they only use 1 for the after start condition, and could I have 1 of the 2 bad?

5.) After the truck starts, and the grids cycle, is the wait to start light supposed to come back on, or is it supposed to stay off? ( Mine never comes back on after the truck starts.) I also say the grids arent firing after the truck starts because I never see the voltmeter dip after start........

I guess thats about it, and dont think I dont want to plug her in, because as soon as I get comfortable that she will start in the cold, I fully intend to plug her in, but there are times where I will be on a job, and cannot plug her in, so I figure I might as well know how to start her without Aux. heating.

As always, thanks for helping out this newbie!

 

I've started mine at 10 below without plugging in, it doesn't like it though and will smoke out five acres.
The grids will cycle on and off as long as you don't exceed 17 mph. The light only comes on pre-start though.
Fuel heater doesn't help with starting.
Easy to check if both grids are working, just put a voltmeter between a good ground and the insulated nut at the base of the airhorn while the light is on.

It could be your timing has slipped causing harder starting.

 

Try manually priming the truck before you try to start it. The manual primer button is down by your fuel heater, below the fuel filter and attached to the lift pump. You can pump it until you hear fuel squeaking past the overflow valve. Then try and fire it up.

Mine would get an air leak once the temps turned colder out. I figure it was the cold rubber lines shrinking up and exposing micro-cracks and letting air suck in overnight. I've replaced the rubber return and supply lines and it cured that problem for the most part.

 

when it does give you trouble starting, does it pop and skip and rumble then clear out with white smoke?

 

Timmy, If you mean by pop and skip, dropped cylinders eventually firing, yes. It never takes more than 10 or 15 seconds for it to level out and purr like a kitten though. As for white smoke, I cannot tell, all my starts with this condition have been pre-daylight. I will hopefully get to start her this weekend during daylight.

Crimedog, I will try that, man I would have never figured something like that one out.........

Bill, It runs pretty strong for slipped timing. I will put the Voltmeter to the grids this weekend though. Do both grids always cycle as a pair, or can they operate independantly?

 

Pat, they always come on together prestart.
After the engine is running they can either come on alone or together depending on the intake temperature.

 

AH HA!

Thanks Bill. I will test them this weekend. I would almost bet that I have either a bad grid or relay. I chatted with the Brother in Law last night ( 97 just like mine with 72K miles, lucky dog...) and he told me he never has any issues until way below 0, but that he sees the voltmeter drop after start.

So it appears as if I need to plug this puppy in tonight to make sure she starts tomorrow and gather up my tools for a run into the shop!

Man, I wish my FSM would show up, it would save a ton of questions on here.

 

Sounds like your grids aren't heating if the voltage gauge doesn't dip after starting. Could either be the relays or the grids themselves. Usually the relays stop working, you can replace them with Ford solenoids for under $10.00 each from any auto parts store. If you search you'll find plenty of threads on that.

Mine starts without plugging in the block heater down to -10 or -20 F, but I do cycle the grid heaters twice before cranking.

 

After sitting for a few days I recently started my 96 at 0 degrees. It fired right up but did rattle and smoke for a while. When the heater light goes out I crank it about 1 turn to draw the warm air into the cylinders, then recycle the heaters and it starts fine.

Have started it as cold as -40, plugged in of course. I use 0W 40 oil.

Dave D(SK)

 

Are the batteries good? I replaced mine and now the truck turns over much faster in the cold. It also starts MUCH easier.

 

You might want to look at the relays on the driver's side fender. I found the supply wire off of one of my truck's relays. So only one portion of the grid heaters was working. My wires are push on with a tension fit and one of the posts on the relay had corrodes/burned over a period of time and got loose; then when working on the truck I accidentally pulled the wire loose and didn't realize it. It has been a while but I think the problem started showing up in the 20's as you described. The truck would still start but got more difficult as it got colder out.

 

Ok, I finally got to check it out pretty well inside at work.

It appears as if all the connections were good, and I have 12V at the solenoid from the Batt, but no 12V on the other side or the grid. I ohmed out the grids, and got right at 1 Ohm between the posts and ground, and about the same grid to grid?????? I really need that service manual to show up!

So, from what I can see, the Solenoids appear to be toast, and the sounds I hear clicking must be from the ABS relay, now that I can hear it without shivering.......

There seems to be some conflicting information on how the solenoids are drug in, does anyone know for sure if you apply 12V or ground it on a 97? There are 2 smaller terminals on the Solenoids, and I am unsure which to either ground or apply 12V to manually engage the Solenoids to check them for sure. I do know for sure there is no constant 12V at either of the smaller terminals.

If I do need solenoids, and use the Ford solenoid, where would the other small wire go to?

On a positive note, at least she starts without grids! I dont like to crank it that much though, it cannot be good on the thing.

Thanks for any further info!

 

I made this diagram from the 97 service manual.

 

To test the relays it doesn't matter which small terminal on the relay you apply + or - to as long as both small wires are disconnected.
Pretty rare for both relays to fail at once, your problem may lie elsewhere.

 

The hot leads to the solenoid are always on when the key is on. The PCM provides the ground when the grids are cycled on. You should be able to ground the terminal and hear the solenoid click AND then get continuity to the grid terminals. Just because they click will not necessarily mean they are working.