Dodge Cummins Diesel Forum banner
  • Hey everyone! Enter your ride HERE to be a part of October's Cummins of the Month Challenge!
1 - 10 of 10 Posts

·
DieselAutoPower.com
Joined
·
6,698 Posts
Discussion Starter · #1 ·
How long should my purge take? My fuel systems will be comprised of a 1/2" big line kit through the stock filter. Into a T with two check valves. The WVO setup will be plumbed into same T as well. Basically I'll use a double pole single throw switch to toggle fuel pumps. Then from the return line off the engine I'll install my pollack valve. This will allow me to send the return to the correct tank.

My question is, how long should the purge take to clear fuel from ~1 foot of hose, the IP, injectors, and back to the return line. Pressures will be around 18psi.

Also, does anyone know of a timer that could be used for purging for my setup?
 

·
Registered
Joined
·
143 Posts
put in a clear filter right after your return valves. Put a die in the diesel and run on veg. switch the valves and time how long it takes to see the color change than add a few seconds. All you want is to make sure there is no veg going into the diesel tank.

Good luck
 

·
Registered
Joined
·
381 Posts
Once this is figured out, you could use a turbo timer for the purge.
 

·
DieselAutoPower.com
Joined
·
6,698 Posts
Discussion Starter · #4 ·
Hmmmm..... I'd need two turbo timers wouldn't I? And I think I'll need diodes as well to isolate them. The valve switches directions by polarity.
 

·
Registered
Joined
·
381 Posts
Hmmmm..... I'd need two turbo timers wouldn't I? And I think I'll need diodes as well to isolate them. The valve switches directions by polarity.
Turbo timer rigged up to allow the truck to run for X time before shutting off.

Key off, turbo timer turns on which you could also use to trigger the purge.

Truck turns off on diesel.
 

·
DieselAutoPower.com
Joined
·
6,698 Posts
Discussion Starter · #6 ·
Nope, that's not what I'm talking about.

They'll be a double throw switch to power the WVO or the Diesel switch. I need the delay to happen once it see positive from either of these two. Then delay power on to the fuel valve. This allows the lines to be purged. I want to limit the amount of cross contamination of fuels.

Not something to run the truck after shut off. I'll cut over when up to temp. Then cut back over before turning onto the road to my house.
 

·
Registered
Joined
·
143 Posts
a vo contorller should do what you want.
 

·
Registered
Joined
·
143 Posts
At the current price for diesel, you will get that back fairly quick and will have a well controlled unit.
 

·
DieselAutoPower.com
Joined
·
6,698 Posts
Discussion Starter · #10 ·
Not really. I rarely drive the truck. I commute on my motorcycle 99% of the time. I picked up a timer today that I'm building. I'm not worried with the diesel mixing with the WVO. But I don't want the WVO mixing with the diesel tank. This timing circuit should do the trick. And only $9.
 
1 - 10 of 10 Posts
Top