Fass Fuel System

I used to run one of my Dodge pickup truck. Haven't ever owned one on a big truck, but I have been thinking about it. The new Fass systems are dead quiet where the old ones were annoying loud. It totally eliminated any worry I had about a dodge cummins lift pump going weak, and ruining the injector pump. I also like the fact that you can get half a dozen+ different filter micron rating choices. Where as on my Davco I get one choice, and its a 50 micron or something like that. Hell, with a Fass you can filter down to 2 micron if ya want!

You might consider the Air Dog system too. I actually like them a little better than Fass stuff for pickup trucks. But, again, I just dont have exp with them on big trucks. I also dont see an Airdog model listed specifically for big trucks (which is stupid) because their fuel flow rates are over kill for any OTR truck.

http://www.pureflowairdog.com/index.html

I wouldnt buy the Fass for the soul purpose of gaining a full MPG. I am doubtful that thats gonna happen, but I can almost gurantee you aint gonna lose any mpg either. Think about it, if you really could gain a full MPG by adding one of these every huge fleet would have them added from the factory as standard equiment. The main benefit (besides better filtration) is the fuel/air seperator. My Davco doesnt do that, not even a little bit!

 

Thanks for the first hand experience Kansas. Why do you prefer the AirDog over FASS? I have no experience with either one, so i appreciate your thoughts on them.....

 

The fuel air seperators just purge the air from heated foamy fuel , they help but to gain a mile to the gallon the gallon that they measure against must have been pretty hot and foamy, real world maybe 1/10 mpg gain would be more realistic and as stated before airdog may have better design

 

the air dog (fuel preporator) and the fass units are very similar in design because it was originally a father/son business and they splt up and the son is the fass owner and the father owns the air dog
when the fuel preporator originally came out it was before the electronic engines and when it was installed on a mechanical engine it made a big difference in performance and fuel mileage but when installed on an electronic engine the perfomance and mileage gaines are not as noticeable however the better water and dirt filtration will add alot of life to your injectors

 

They give you great filtration,constant pressure to pump,i have only seen 1/10-2/10 mpg at best. I would buy another one.

 

Originally it was the noise of the Fass that turned me to Air Dog. Since they have "fixed" that issue I think its just personnel choice currently.

If it was me, I think I would just shop around to make my best deal. Double check the price of replacement filters too.

112Racing nailed it with his post. Great info IMO.

 

Old man had a FASS system from Pittsburgh power on his last truck, 2000 Freightliner FLD120 with a 3406E 550 CAT, 2WS serial I think it was?

He installed the FASS and seen about 0.4 MPG improvement, much smoother acceleration and the throttle was very responsive and immediate, I would put one on any truck I would own.

 

AVOID. I had a Fuel Preporator in my truck for two years. My truck came with it when I bought it. I took it off about 8 months ago. It was fine if you have extra filters with you, but beware it it starts plugging up and you do not have a filter. The only filters that fit the device are the ones that you must order from the company. That happened to me in Houston, and I had to undo the hoses and bypass the thing in a parking lot. Also, mine required motor brush changes (the new ones don't). My motor finally burned out. A replacement motor is a mere $280.00. I repair everything, so I grabbed my Grainger catalog and started to match up motors, but I discovered that the motor in the Fuel Preporator is skillfully crafted so that it cannot be removed from the gear pump. So I removed the Fuel Preporator from my truck. Want one? I will sell it for $50. Comes with mounting bracket, wiring, two water separator filters, and one hose. Just order the replacement motor and get a couple of the fuel filters and you are in business. I have photos if you want to see what it looks like. My engine is a 500hp N14.

 

I have been running a FASS (200 GPH system) for the past 2 years. The product and support have been great. The filters use to be a issue, but since more and more guys are running a FASS system companies are starting to stock them. The only way a person will see a big gain (1 MPG) is if there primary filter and housing has a flow issue or is leaking air into the system. Besides that you will only pick up about .1 MPG, but the motor will pull consistent through out the day. Like was stated earlier the filtration is way better and that was why I bought it. Also changing fuel filters are a snap now. All a person has to do is install all 3 filters (2 on the FASS and the secondary) and turn the key on. By cracking the bleeder on my CAT the system will purge itself in no time.