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Original post by: Darrell ,


Well, I installed the one I have on my Volvo D12, this FASS unit was on my 1 ton dodge truck, I had that Cummings bumped up 150 hp.

It took me less than two hours to run the new/separate return line to the fuel tanks. I then removed the Davco filter that was mounted on the drivers side between the front tire and the engine. The Davco filter was mounted on a good strong bracket so I used the mount plates that came with the FASS and mounted it there. All you have to do is take the in and out fuel lines off the Davco and put them on the FASS. then run a separate return. I had two 3/8 plugs near each filler cap on each tank, I just removed them and put a fitting there.

Here is where I had problems, both with the manual that I downloaded from FASS that applied to my engine, and with making sense of the instructions.

FASS could not tell me how to decipher the instructions. I went online and downloaded the Volvo service bulletin that gave me a really good view of the fuel system.

I then faxed the print to FASS and asked them to tell me where to tap into the return off the head.....this is the benefit of the FASS by doing this properly....this returns the hot fuel from the head back to the tanks.

I will not say it saves fuel, gives more power, or the engine runs smoother....but I think it does.

What I will say is I know that I am getting more fuel delivered to the gear pump under pressure instead of under suction. I'm positive I'm getting cleaner fuel, no water and no air in the fuel...and no hot fuel going back into the fuel loop.

On this engine, the ECM injector control banks in the ECM are cooled by the fuel that runs through the ECM. This should give my ECM a little heat relief.

If anyone has had fuel delivery problems after installing the FASS then it probably had a bad install....if done right I think it is a benefit.