I had two springs for the FASS and with the weak one stretched I had 15 idle and no lower then 13 pulling, but the stretch would come out and drop it down a couple of pounds.

I tried the stronger spring, now have 19 to 20 idle cold, 18 1/2 hot idle. Pulling is 17 at the lowest and cruises at 18. It does not have a starting problem and probably has a higher return with the higher pressure.

Does anyone think that will be detremental to the VP44?

I also installed the Baldwin 5 micron filter. Checked with Baldwin on their web site to make sure it was a 5 micron.

I get a lot of time to think about these things on the road. I have never heard mentioned that the FASS has such a high return flow through its own return that it filters the fuel many times an hour, circulating the fuel in the tank. There is something superior to the crank driven system. I believe the filtering is much better than using the stock filter system. In stead of haveing a closed circuit regulator the circulates within the pump, the FASS returns the excess to the tank through the vent system. It returns enough that you cannot fuel with the pump running.

 

I raised the fuel pressure at one time on a customer's truck and it caused a leak in the fuel heater on top of the filter, right where the wires come out. Had a few miles on it, and may have just been coincidence, but who knows. That was only like 16 psi., but more than that engine had ever seen.

 

I've heard of hard starts with fuel pressure over 16psi.

Seem to remember injection pumps not liking much over 16, but don't quote me.


phox

 

In my case the VP44 is all there is of the original system. It goes direct to the VP from the FASS and it draws from a bottom feed. I think there are a bunch running as high on the board.

Seems that I remember a post the named 22 or something like that as the max. I could not find it though.

 

I remember back in 98 , we had hard starting problems and the fix was a calibration downloads to lower the liftpump output at start up, I dont remember the psi but I dont think you will have a problem with 19 psi .

 

i have a pusher pump,and a healthy lift pump. i idle at 31psi all the time, i run down the road at 25psi at 70 mph,ive never had a problem. its been this way over 2 yrs and 55k miles,total of 100K, i have the original Vp44 and an edge drag comp.

 

John I have 2000 normal running miles on it as it is now. No problems. But I do wait for the pump to stop, don't start it till the wait to start goes out. Odd too, because with the stock pickup when I first put the FASS on 16 caused a problem sometimes. See it starts at 0 pressure.

 

Thanks, I though that was the case.

 

Haulin out of curiousity do you know what the stock filter is rated at? All I get out of your post above is you are getting more filtered fuel. If thats all a guy wants why not just put a inline filter in the supply line? Have you seen this thread?
http://www.turbodieselregistry.com/f...1&page=1&pp=15

 

I can testify to the hard starts. Since installing my pusher pump, I now run 22lbs at idle and 18 WOT. However, if the truck sits for a short time after it warms up it will crank for a few seconds before starting. This was not the case before installing the pusher pump.

 

Opie the stock filter is 10 micron. I was referring to the fact that the fuel is constantly circulated through the filter system with the FASS, not just one pass througth as in the stock system. On my system the FASS has been the cure all for the fuel system, the extra filtering is just a plus.

 

I am not having that problem at all. But the system is never over 20.

 

Haulin_in_Dixie

Thanks for the info on the stock filiter. I don't know what Bosh recommends to Cummins/Dodge that the fuel needs to be filtered at for the VP44. I am sure they would be very satisfied with your 5 micron though.
The only downsides I have read about the return system you mention is it makes it tough to add fuel with the engine running and that it causes the fuel to foam in the tank. What are your thoughts on the fuel foaming?


Opie

 

Opie foamed fuel is simply fuel with immense amounts of air in it. The FASS is primarily designed to remove air. At any rate the current setup that I have is operating flawlessly. When cold the pressure is 18 to 19 and when hot after pulling loads it runs 17 to 18. I did notice a slight pressure drop (1/2 pound) with the 5 micron filter on hard pulling. One day I will add a new bonk to the tank for the return, maybe with a tube to keep the flow below the air.