Hello,
while making some adjustments to my injection pump after installing it i was considering increasing the curb idle speed as much as would be practical for a particular reason: i tend to idle my truck a fair amount, sometimes over 1/2 hour and once in a while for an hour, and i have been told that can coke up the injectors. The reason i do so is because i have a two-tank svo system, and it means having to purge the system with diesel before shutting down, and then starting up again on diesel before switching back to free and clean veggie oil. Petro diesel was never part of my plan and soon i will replace even that with biodiesel (home brewed).
So since i have to idle a bit more than others (and my truck doesn't have the high-idle gear that the big rigs do) would it make any difference if i increase the curb idle considerably, in terms of slowing down the inevitable coking of injectors? And how do i know when the idle speed is too much?
Any help appreciated as always. thanks,
Paul
:ro)

What about hooking up a manual switch to run the Fast Idle solenoid and adjusting it to the idle speed you want? Just unplug the factory connector so it runs the cold advance solenoid but not the fast idle. All you need is a hot wire from the batt or fuse box, a switch that you can mount in the cab, and a female blade connector to hook it to the solenoid.

Alot of Ambulances have high idles wired to the parking brake.... would be an easy way to do it, when you set the brake, it triggers the high idle... :-D

I did what TDG is suggesting. Very easy.

thanks for the advice, i will have to try that. Does that mean that everytime i start the truck i would also want to hit that switch, or only when it is cold out? If so, how long would i leave it on for - just a few seconds or what? thanks,
Paul

Just flip the switch when you want fast idle, flip it off when you want normal idle speed. Its up to your discretion when to use it.

I went all all manual when my glow plug controller failed. I use fast idle for start and to keep oil pressure higher when we are stopped in hot weather. It is off the rest of the time (unless I forget).

Is the fast idle solenoid originally meant to kick on each time you start, or just when it is cold out?
Paul

Fast Idle and Cold Advance are both operated by a coolant switch, which is closed until coolant temperature warms up.