James342

98 12v 40 degrees and truck has a hard time starting.could it be bad injectors or a fuel problem?

patdaly

Probably none of the above. When you say hard start, what exactly does that entail? Long crank times? Have you tried feeding it just a bit of pedal while you start it? The owners manual says give it 1/4 throttle below 50 degrees I believe ( could be 60 ), but I have found you don't need anywhere near that much, I feed it about 1/16 throttle and she lights right off.

Anyway, DON'T mess with it until we talk this through, and describe the start both warmer temps and the cold temp problem you have and lets see what we can figure out.

James342

at 40 degrees outside temps I’ve had to crank it over 4 to 5 times before finally giving it about 1/4 pedal and it fires up.i cycled the grid heater to make sure that it wasn’t the problem and it was warm but not hot.it seems to me that it shouldn’t be that hard to start with those temperatures.could it be that the timing is off?
This is my first winter with this truck.

patdaly

Nope, the owners manual specifically says 1/4 throttle below 60 degrees, this is just one of those P7100 pump truck things. I give it a bit of pedal no matter the temp anymore just as a matter of habit, mine starts like a VE truck, first turn of the starter.

You don't even need a grid heater until it gets pretty doggone cold, my 4BT 79 GMC has no grid heaters and she has started at -20F, not easily, but it did it.

For this winter, make sure you have HOT batteries, and the starter is in good shape, past that, make sure your fuel filter is relatively new ( I change mine about every 20K miles, but they can go longer if necessary. ( We have good clean fuel around here )

You should be fine, I go back to my first winter with one and try and remember how freaked out I was.........

James342

I appreciate the information! I’ll replace the fuel filter,I’m sure it needs done.my first diesel was a 24v vp44 so i was used to it firing right up when it got cold.

patdaly

LOL, everyone raves about the P7100, and while I agree it is a pretty bulletproof design, it isn't as driver friendly as either of the other designs. One thing that even I forget until I have to change one is the speed at which a new or properly rebuilt starter whips these things over at. I just had to throw a new starter on mine after 8 years, and before even with a tick of pedal, it would take 2 or 3 revolutions to light off, now the additional speed of turning by the fresh starter, it lights off instantaneously.

James342

It had a brand new starter when I bought it,unfortunately the previous owner didn’t put the bolts in tight enough and it vibrated loose on the way home breaking one of the ears off.2 hours after buying the truck and I had to invest $200 in a new starter but I love this truck,almost 20 years old and I don’t think I would trade it for a brand new one!

sewman

Might want to make sure the heaters are working?

AlpineRAM

I would also suggest that you check your idle speed.
It should be at least 750 rpm with the engine at operating temperature, AC on, automatic in drive.
Anything lower can lead to hard starts, engine stalling when going back to idle etc.