Community Forums

jhDakota · 08-28-2015, 12:33 PM

How do you stop the fuel from continuing to flow while changing the filter? When opening the valve to release the water, I had drained far more water and then fuel than it appears the filter would hold. If I unscrew the filter, will fuel continue to flow?

FRR2EYW · 08-28-2015, 12:40 PM

I have a Freightliner chassis and there is a valve in the line just before the fuel/water sep. and yes, fuel will continue to flow on my rig.

JumboJet2 · 08-28-2015, 08:25 PM

Just changed mine twice. Fuel did NOT flow either time. I did have to change the inline filter upstream that was plugged. Mine might flow fuel next time.

TANDD · 08-28-2015, 09:39 PM

I changed mine, did NOT continue to flow. ISC 330. What chassis/motor?

Jim Woodard · 08-29-2015, 08:41 AM

Cummins ISL 350. Just observed my mechanic change the fuel/water separator so I could do it myself the next time. It sits low near the right/rear jack and tires. The engine was off, of course, and he just unscrewed the old one, after unplugging a sensor. No fuel flow, so I'm guessing there is check valve that closes when the engine is turned off. The new one comes with a rubber bushing that replaces the old one, that's the first chore, then the filter is primed with diesel fuel until it flows over, then he screwed the new filter on quite a bit tighter than what you might do on a regular car oil filter. Then he plugged the sensor wire back in, and off I went.

Jim Woodard
2004 Dutch Star
Fort Myers, FL

Gary RVRoamer · 08-29-2015, 08:53 AM

Some flow and others do not - all depends on the location (above or below the tank level). Mine (2004 ISL 400) flows steadily, but I just have the new filter ready to screw on and be quick about it. Some chassis have a valve, but more typically they do not. You may be able to pinch the rubber fuel line with vice grips or forceps if you like. Not a big deal if some leaks out - just put a pan underneath to catch it.

You are getting a lot of water? THAT is something to be concerned about! Should be none, or occasionally a few drops. More than that suggests the tank has a lot of water accumulated and that is going to cause trouble sooner or later. Keeping the tank near full when not in use helps keep condensation down. And you may want to reconsider where you buy your fuel, if you mostly use the same source. Some places have a lot of water in their underground tanks.

Triker56 · 08-29-2015, 11:14 AM

My ISB W/S will flow some.
I bought a extra Bowl and then have the replacement pre filled from the outside holes.
Then very little loss when a quick change out is done