"Prime" the fuel system before starting?

[The_Josh_Bear]

Josh an interesting theory. Do you think the pressure just drops to zero or do you also believe the line drains between pump and injector?

My owners manual has this to say about starting. Temp above 32 f depress accelerator pedal 1/2 way and hold. Temp below 32 f depress accelerator fully and hold. Warm engine start with pedal at idle position.

Pressure drops to zero inside the line, or at least very low PSI. Then it takes extra revolutions to prime it back up, because remember each stroke from the IP is just a tiny bit of fuel. However I don't think air can get back up into the lines unless the injector pintle is super jacked up/bit of sand is in there.

Could an overnight tranny fluid treatment help with that or would it need a rebuild?

Certainly could, mostly depends on what kind of lubricity you already use. I'd give it a go anyway!

5-8 seconds is not long enough, when iwent to a push button glow plugs, I took a glow plug out and hooked it up to 12 volts and I counted to 14 before it got glowing red. I also have a electric fuel pump.

I'm in this camp as well from the testing I've done. 8 seconds for my pickup even in the summer, 15 for anything under 32F around here. But I wanna try your way, Brian, to see if it changes starting ease.
I've done a bunch of bench testing with genuine Beru ZD9's and they don't glow red at all before 10 seconds, kept getting brighter till about 15 seconds. That was at 65*F ambient, not 20*F.

 

[ihc1470]

Pressure drops to zero inside the line, or at least very low PSI. Then it takes extra revolutions to prime it back up, because remember each stroke from the IP is just a tiny bit of fuel. However I don't think air can get back up into the lines unless the injector pintle is super jacked up/bit of sand is in there.

Thank you for you thoughts on this.

 

[The_Josh_Bear]

@Brian VT I tried your "prime" method of 4 second crank then 10 second glow plug cycle, barely started, and I had 3 or 4 poorly firing cylinders for a bit. So whatever's going down with your setup isn't the same as mine, that's for sure.

To me it sounds like that setup works well for consistent starts, I wouldn't fret too much. Have you deleted the line from fuel filter header to #1 return?

 

[IDIBRONCO]

I can say that I had to do the same thing when I had the other IP on the engine. It had a seal by the timing advance that would leak fuel externally when it got cold outside. It would start in around 55* with a slight miss when the engine started. By the time that it got down to freezing, it would be a bad miss. If it was less than 30*, I would crank the starter over for about 10 seconds and then hit the glow plugs. That always seemed to help. I know that the engine would start down to 3* without being plugged in, but I didn't try it much lower than that after I found out the the block heater stopped working.