Archived My new FASS dont work!

[rkapperman]

My new Fuel Air Seperation Systems (FASS) Works GREAT...

I found that my fuel pressures were about 8 when idling and 3-4 pounds when accelerating. This I believe to be my problems with hard to start etc...

So I purchased a F. A. S. S from Schied Diesel in Terre Haute. I haven't had a chance to confirm with them yet but does anybody know how much vacuum this pump generate to pull fuel from the tank. It appears that I have none (zilch, notta) and this would explain why I don't get any fuel to my gauge at my injector pump. I have double check the hookups and all seems to be correct. The "T" marked connector is for the TANK connection which I believe this is where the pump will get the fuel, "E" is for injector, "R" is for return. Also I remove the connection to "T" and turned the pump on for a moment and found no vacuum. The direction said it was not necessary to prime the pump but now I am not so sure. But even so shouldn't there be some vacuum in order to draw the fuel.



Here is some more INFORMATION

I have the FASS 150/95-D0-98-04 (95 gph) model. One thing that I noticed is that the fuel filter had enough fuel in it when I removed it to see if any was getting to the pump but I am assuming the return line had enough fuel to back fill the filter. This I checked right after I noticed the fuel pressure on my gauge go to about 20psi and then drop off and not regaining any pressure after that point. I might assume from the installation instructions that the pump is basically installed higher than the fuel tank indicating that is must pull the fuel from the tank like the original pump did. I have not read in the installation manual that an addition lift pump is needed. Have you ever run the tank dry and then restarted without priming the system again? Did you prime the pump when you FASS was installed? Maybe once a prime is achieved the pump will have a better internal seal to create a vacuum from that point on!



GOOD NEWS.....



It works great now!!



Its great to get feedback from questions like this one, the TDR has turned out to be a good forum for sharing information. I finally got everything primed and all seems well now with both stock and Aux. tanks. Special thanks to TST Products and Dave's Diesel for listening on behave Diesel Performance Products support network. It is nice to see such willingness to help!!



PS look through my replies to see what I finally did to complete my venture.



I have a 2001. 5 3500 HO 6-speed man. Stock(at least till the pump went out)

 

[rkapperman]

Here is some information I pulled from Diesel Performance Products that gives some clues about the operation of the pump. The way I read it the pump should generate vacuum.



Real World Conditions



In the real world, the fuel tanks are usually mounted at least two (2) feet below and ten (10) feet away from the fuel pump, This configuration creates multiple problems associated with the fuel delivery to the engine. First, the injection pump has to draw the fuel from the tank by creating a vacuum. When diesel fuel is drawn by a vacuum fuel vapor is produced. Second, while the vehicle is underway the fuel is sloshing around in the fuel tanks creating entrained air. This circumstance has created a situation far from the test cell conditions which results in air and vapor being mixed in with the fuel when it is delivered to the injector. By having entrained air and air vapor in the fuel the engine does not perform at the engine manufacturer's specification. Air and fuel vapor occupy the space that should have pure fuel, thus delaying the injection of fuel into the combustion chamber. This phenomenon is better known as "RETARDED TIMING. " The air/vapor present in fuel is very inconsistent making it virtually impossible to adapt the varying degrees of changes in injection timing. The retarded injections cause a multitude of problems in the combustion chamber!

 

[Sticks]

First and foremost, do you have fuel in the tank?



Second, double check your connecitons at the tank, making sure that your pump feed and return are hooked up to the right fittings.



Check all your connections to make sure they are tight (READ - not able to draw ambient air into the hose)



Are you getting any fuel flow at the VP? If so, but you are still seing no pressure, you may have to replace the overflow valve (fitting right next to the VP44 inlet banjo to the left). This is what is creating the pressure in the supply system. If you have a buddy with the same model truck, swap the overflow valve with him (her) and then test it.



Fluid hydraulics 101 - Pumps create flow, resistance create pressure.

 

[tractorface]

Having some trouble following you. The system is easy to prime. Prefilling the filters will make the process easier. Loosen the filters and cycle the key to get the pump to run Listen close and when you hear the pitch changing( fuel is coming) tighten her back up. If dry it may take a couple of cycles. The seperator will fill first after that is tight then the secondary filter will fill and you should be good to go.

 

[bpenrod]

Do you hear the pump running? Mine always spikes the pressure up when I turn the key to ON but drops off while I wait for the WTS light to go out. The truck will turn the pump off if it sees the key on and engine not running. By the way, your original numbers looked OK, I used to get a vacuum at the CP3 under full throttle!

 

[rkapperman]

Update to "My new FASS dont work!"

Let me explain what I said to a FASS Technician. I have two tanks (stock and 115gal. in the bed) both which I admit is between an 1/8 - 1/4. My fuel switch valve is located half way between the tank and engine compartment just before transmission cross-member. I then had to take the common line for both tanks suction back to the FASS unit located under the bed in front of the dually's. This puts about 6feet from tank to switch and 6feet back to FASS. With that said, I bought a $7 prime bulb used for marine fuel applications and placed in about 2feet away from the aux. tank output before my tank filter I have mounted in the bed of the truck. I proceeded to prime the pump with the prime bulb and the pump built pressure(20psi) right away. I ran the truck a few minutes then switched to the stock tank and I noticed that it dropped to 0psi quickly switching it back to the aux tank and every thing seemed ok. Drove the truck around the block ~2minutes and found the pressure drop again. I also noticed the route of the common hose from both tanks is above the stock tank. So I wonder if I should route as much of the hose below the stock tank to help prevent the fuel from ciphening back to the stock tank? I also wonder if the stock tank has a check valve and since I am not using a vane pump(stock) anymore which probably does a better job of creating a vacuum if I should use a check valve to prevent the backflow of fuel? I will do some test to get more detail of behaviors of the FASS pump on the length of hose I have and maybe this will shed some light. Has any body done draw test with various length of hoses. It would seem that any air in the line will cause me to have to re-prime?????

 

[Jlobaugh]

is your prime bulb in correctly? could it be a one way flow bulb? could you have a bad valve or trash in the valve that this pump is moving that the old pump couldn't move? I am stumpped .

 

[rkapperman]

The F.A.S.S Works and I think I like it.

I finally installed a Priming bulb at the fuel line coming out of my Aux. Tank and was able to prime the line easily and the pump took off immediatly. I then proceeded to test both tank supplies and noticed that the stock tank supply didnt seem to take to prime as well. So I went to my fuel switch and routed my line to the pump low and inside the framerail until I reached the pump then went up to the inlet. This step I believe will make it harder for the fuel to drain back to the stock tank. The line was ran to the pump on top of the framerail before which I think contributed to added pressure to drain back the fuel to the tank. I have not seen any problems with priming the pump since that point. My biggest concern was if I ever got into a situation where on a hill and a low tank could I loose prime and have to fill filters and somehow fill the lines again on the road with minimal resources. This I believe makes the priming bulb from your local marine supply of even fishing store the best safety net I could have in that situation. I can use the priming bulb and even see the pressure to the injector where my gauge is located. Since I can prime this way it shows how much flow through the pump has even when it turned off. This explains why I had such a hard time priming the system to start. Last night I ran on my Aux. Tank for 30 miles then shutoff the truck to visit my brother and then ran 30 mile back home on the Stock Tank and found no issues while accellerating or cruising. The truck started just fine today WITHOUT priming with my handy-dandy priming bulb. The initial reason I replace my stock fuel pump was because I having problems starting the truck and it was like bogging down when I first start to drive after being shutoff for a while and then it would pep up in about 5 seconds of driving. So I installed a pressure gauge to confirm the pump problems and I noticed 8lbs idleing and 3lbs accelerating with maybe 5lbs running pressures. This I believe is what was causing all my behavior problems and some of the Codes I was seeing(PCU 1693,ECU 0216). I need to clear these codes and see if any codes are still present any ideas? The truck seems to run/accelerate/idle/start just fine.

 

[Andy Redmond]

Your oem tank module should have a ck. valve on the supply side above the screen, unless you have a leak on the inside of the tank on the supply side.



The FASS doesn't have a one way ck. valve to hold prime?



You stated pressures near the bottom on your most recent post, Good oem lift pump or Fass should do way better. .



Good luck, let us know what you find.

 

[AKAMAC]

If you had posted codes first you may have be given advice to take it in for warranty repair. Sounds like the VP44 is headed south. Mike

 

[rkapperman]

I have 114K on the original Fuel Pump. Warrenty is out of the question anyway. the FASS runs about 20psi and 14psi at is lowest on accelleration. I still noticed that the hesitation was still present today when I drove it. Earlier I explained not only was it getting harder to start I also noticed a hesitation "bogging down when I first start to drive after being shutoff for a while and then it would pep up in about 5 seconds of driving". Is this a physical problem with the VP44 or just the electronics gone bad with not enough cooling from low fuel pressures? ANY IDEAS...

 

[AKAMAC]

I'd be searching for a new VP about now. There are sponsors to the site that have good pricing and service. Look around and do your homework. The electronics or the mechanical portion can fail. Mike

 

[rkapperman]

Thanks, Mike. I would like to understand why and how and what actually is wrong with the VP-44 it just might mean like you said a little more homework... Good-Day