FASS Problems

Smokinrebel

Smokinrebel

New member
Joined
May 22, 2008
Messages
4,141
Two weeks ago i put a FASS 150 gph on my buddies 02 24V. Went on fine no problems. He has a Juice with Attitude, and stock injectors. He put a T in the line to the injection Pump the other day for his FP gauge to screw into (electric gauge for Juice) Bleb the line afterwards to get air out. It was reading good FP right at 16 ideling and holds strong when pulling too. Yesturday the gauge started reading weird pressure, going up and down spuratically. All the way down to zero. But not cutting out. He got to where he was going and shut the truck off, went and did what he had to do and got back in it and the truck moved 10 ft then shut off. Wouldn't start back up. So, this morning i went and helped him try and get it started. For some reason the whole system was just about try...the first filter was full, the second filter was half full. So, i cracked the #1 and #3 injector lines and primed and primed and primed the pump until we got fuel. Started it up finally and closed the lines. Started driving and the FP was going nuts again. Went and drove it about 3 miles and it started chugging and shut off....BY the way the injection pump is brand new too, he just got it replaced thats why he got the FASS.

So, i am at a loss for what could be wrong. Does anyone have any ideas?

Thanks
Brian
 
Check the suction lines. Also to reprime the fass I just loosen the filter.
 
we pulled the suction line off and put it back on...it looked fine. Also took both filters off and put them back on. It ran fine for a little bit then shut off...i can't figure it out...except that maybe the FASS was a lemon
 
Well erratic pressure is very odd with the FASS. Here are some suggestions i would try:

You have a J-WAM you are using to monitor fuel pressure. I would start by double checking the gauge right off. I know we had drivability issues here..but i ALWAYS like to confirm the gauge is reading correctly...especially an electric one that is on a VP-44 truck....those pump pound sending units like crazy.

Second, we need to see if we got any restrictions. Did this truck have an in-tank pump installed? I have seen our systems run for some time when trying to draw though an in-tank pump. Then randomly just stop pumping due to excessive restriction. I would try the 5 gallon bucket test: Get a bucket, fill with fuel. Place FASS return and suction lines in the bucket. Crack fuel filter on FASS until primed and run system. Observe pressure and listen to the FASS. If the unit runs normal i would say that we need to look in the tank for possible issues.

Lastly...going on the same lines of David......what is the fuel level in the tank? Sending units have been known to stop working, jam or hang up (Especially if you installed a draw tube and the float was hitting the tube....and based on the time frame with moderate driving...that would be about a full tank of fuel...at least for me it is). Try putting about 10 gallons in the truck and see how it does.
 
The FASS pumo was shot on his truck. We checked all mlines and filters and had no restrictions. So he took the feed line off of the tank and put in into a cup of diesel and it would not suck the fuel out of the cup. The dealer he purchased it from is sending him another.
 
Smokinrebel said:
The FASS pumo was shot on his truck. We checked all mlines and filters and had no restrictions. So he took the feed line off of the tank and put in into a cup of diesel and it would not suck the fuel out of the cup. The dealer he purchased it from is sending him another.
Click to expand...

OK....news to me....and im the guy that approves wnty for all pumps.....you might have his dealer call me before he ships out a brand new full kit, or talk to your bud and have him or you call me when the pump arrives.....i would like to talk you guys though what needs to be done so serial numbers don’t change.....PM me about it....
 
To add....i dont feel that this situation justifed a new pump.....i need to talk to someone on this before the new pump is put on......get some more info on whats going on....there might be a simple fix that we are missing here....
 
First and foremost, the most often over looked item is the vents to the tank and unapproved fuel caps.

This will cause a negative restriction and burn any pump up.

I ran into this problem a few weeks back where a customer from out of town had one installed . The tank vents where completely plugged and he had a locking fuel cap that did not vent.

The FASS will pull tremendous amount of fuel and will darn near pull the sides in on a plastic tank if not vented properly.
 
That's why I leave the filler cap on mine loose. I just place it on top of the neck.
 
MAXTORQ said:
First and foremost, the most often over looked item is the vents to the tank and unapproved fuel caps.

This will cause a negative restriction and burn any pump up.

I ran into this problem a few weeks back where a customer from out of town had one installed . The tank vents where completely plugged and he had a locking fuel cap that did not vent.

The FASS will pull tremendous amount of fuel and will darn near pull the sides in on a plastic tank if not vented properly.
Click to expand...


This true...the FASS is returning slightly less than what its taking out of the tank just due to engine consumption. Short of fuel heat...it will pull a vacuum over time if not vented.....

Whats up Rob?
 
Trying get our Project Truck done. That 45psi pump we got from you will flat out push some serious fuel.
 
You must log in or register to reply here.
Back
Top