Please explain difference between run and purge time

[Elvia]

James Could you explain the difference between run time and purge time. If the run time is 52. something seconds and purge time is 10 seconds, I guess I need some educating. If it only takes 10 seconds to purge from the injectors and rails, whats the extra time for?

[captgrady]

I understand it as purge time and burn time, burnin' off oil left after purge, why it takes a while to change smell.

[Fordnut74]

Well I am not James, but hopefully I can provide an educated answer. Purge time is the time it takes to evacuate the fuel rails of VO. Run time is the time it takes to evacuate the injectors themselves of oil. The engine itself uses about an once a minute at an idle. The fuel rails hold about 1.5 ounces a piece for a total of 3 ounces. then each injectors holds about .25 ounces, which equates to another 2 ounces. Then figuring a 50% safety factor, we shoot for about 10 ounces on purge. The purge itself only takes aobut 6-10 seconds. But we can not "quick purge the injectors, so that is where the engine run comes into play.

[triplemoutdoors]

Good question Elvia! Thanks Jason for the answer. I have had a few starts where the truck surges over and over but it did that on diesel too so I never messed with the runtime. Right or wrong I just put my foot on the gas pedal until it smooths out.

[SC Grizz]

So if you are a few miles from home at the end of the day and switch the system to the off position, you could be assured that all the VO is replaced with diesel and avoid the running after you shut the truck off?

[Elvia]

Yes, but you would burn lots more diesel that you would have to burn.

[Clay]

So if you are a few miles from home at the end of the day and switch the system to the off position, you could be assured that all the VO is replaced with diesel and avoid the running after you shut the truck off?

Yes you could do that but this system is designed so that you don't have to do that...IF you set the purge timmer to a full 10 seconds and then let it run 1 full minute after that.
The one minute run will burn 1 oz of fuel.
The one minute run time is also a good "cool down" time.
Anytime i turn my system manual off, i run the chance that next time i get in and drive, i will go 20 miles before i realize it is still off and i have just used a gallon of diesel. That happened the other day as a matter of fact.

[Clay]

Read this

http://dinofuelalternatives.com/DFAforum/forumdisplay.php?f=8

[Elvia]

You're right about that Clay. I often forgot to turn system back on a few times myself. Now when I turn it off for some reason, I turn it right back on when I shut the engine off.
Also, I just timed my purge card and the led goes out between 2 and 2.8 seconds over three cycles.
I am going to increase the time to 10 seconds today. That should eliminate the hard starts in the mornings.

[fiveohpatrol]

What would be a sufficient distance to drive to get the same effect of the shutdown purge? The reason I ask is because I really don't want my truck running in the garage for that long when I get home. I figure that at 15mpg average, I'd burn about 1oz in a little over 1 tenth of a mile. My road is 2 tenths long, so it would be easy to remember to shut it off right after I get on my road.

[powerstroke73L]

What's the longest you can set the truck to run? I'm scared enough of injector coking that I'll sacrifice a few ounces of diesel everytime I shut down. Plus as Clay said, the "turbo timer" effect certainly doesn't hurt. I've never been good with letting my truck idle down (maybe the damage has already been done), so I'll set it for two minutes if I can. At current prices ($4.30 a gallon), diesel is about $0.03 an ounce, so I'll gladly spend $0.06 every time I shut my truck down if it means my injectors are safe.

[Clay]

What would be a sufficient distance to drive to get the same effect of the shutdown purge? The reason I ask is because I really don't want my truck running in the garage for that long when I get home. I figure that at 15mpg average, I'd burn about 1oz in a little over 1 tenth of a mile. My road is 2 tenths long, so it would be easy to remember to shut it off right after I get on my road.

Turn it off a few hundred feet before you pull in the drive and let it idle untill you undo your seatbelt and grab your groceries or whatever then kill it.
What would be the problem with it continuing to run for one minute in the garage?

[fiveohpatrol]

What would be the problem with it continuing to run for one minute in the garage?

I spend a LOT of time in the garage, and I'm assuming the smell would get old, or would make me fat because I'd want to run out to a drive-thru

[Clay]

I spend a LOT of time in the garage, and I'm assuming the smell would get old, or would make me fat because I'd want to run out to a drive-thru

Dont shut the door untill it has shut off and aired out a minute...
I personaly love the smell if diesel fumes in the morning as well as the clatter of the diesel engine

[greasyX]

diesel fumes

reminds me of the good old days,getting the fluids up to spec ,and then kick the tires and light the fires,Boy do I miss driving over the road.You could always invest in a exhaust vent hose for $80 at the auto supply store of your choice