View Full Version : Water in Fuel warning?

07-12-2009, 01:29 PM

We've had some leak issues on the full body slide-out of our '08 T40F Tour Master. Every time we get the RV in to the dealer, the stave off more of the leak, but still have not resolved the problem entirely. In the interim, shortly after the last leak, we started to get a warning indicator for "water in fuel." The fuel level was relatively low and we've filled up a couple times since then.....and we still get the same warning despite having added a significant amount of what should be non-tainted fuel. I understand that there's a filter that's supposed to eliminate small quantities of H20 when they creep in to the system and the warning light is designed to let you know that the filter system is working.

Questions are: Am I the only one lucky enough to have this problem? Could the water in the fuel system be related to the full-body slide leak (I would hope that the fuel system would be completely closed and leaks elsewhere would not affect the fuel supply; however, once again, the idiot light started to pop up after the last leak)? Lastly, how worried should I be about the light? The rig seems to be running fine despite the warning indicator and there's no defined power difference. I'm actually wondering if I could have a faulty indicator light.

Any thoughts would be appreciated.


Arthur Hayes
07-12-2009, 02:37 PM
Mike, sorry to learn about the water leaking into your slide, but there is no way that that has anything to do with water in your fuel. You have a fuel water separator with a collection bowl at the bottom of it. When enough water gets collected in the bowl it creates a contact between two probes in the bowl. Adding more fuel to your fuel tank will not remove the water. You can drain the bowl but if you are not familiar with the system, take it to any Truck or RV repair facility and have them teach you.
Generally the fuel water separator is located on the frame rail near the engine.

07-12-2009, 05:51 PM
Thanks Art. I'll try to find the water separator bowl and see what I can do about draining it. Worst case scenario, we have a freightliner service center not too far from where I live. I could have them drain it and give the rig a once over before we hit the road in another week or so. I appreciate the guidance.

Best regards,

07-14-2009, 10:03 PM
Mike, Following-up on Art's comments---the separator bowl has a button on the bottom. Press it and the water will drain. Don't look for a large bowl as it is relatively small clear plastic. If there is further water in your system that is an issue I can't address. Charlie