6.7 Diesel Fuel/Water Separator Draining

[seahunter]

Hello,

My owner's manual states to drain the fuel water separator when the computer indicates it is time. I know the frequency would vary depending on fuel used, but I cannot find anywhere in the manual an approximate mileage for draining it. I have 5,000 miles on the truck now, with one oil change but have never drained the separator. I do not know if they drained it at the oil change - would that be normal? Is 5,000 miles a lot without having to drain the water separator? Engine seems to be running fine. I get about 17-18 mpg without trailer, and about 11-12 towing.

Thanks for any help.

[Fire5er]

I try to do it once a month. Below is a link to a discussion on the subject.
http://www.thedieselstop.com/forums/...onthly-286848/

[seahunter]

quote:Originally posted by Fire5er

I try to do it once a month. Below is a link to a discussion on the subject.
http://www.thedieselstop.com/forums/...onthly-286848/

Thanks a lot for the link Karl!

[Denfinger]

My Ford Dealer Service Manager told me to drain it when the light comes on but certainly doing it more often does not cause any harm. Just like the DEF tank, I don't wait until it tells me I have 500 miles left. I fill it up frequently.

[mlh]

The high pressure fuel pump on any of these trucks are VERY fragile. Even a little water in them can ruin them. They operate at up to 27000 PSI. Draining the filter is always a good idea. If you see water in fuel warning light pull over to the side if the road and drain it, do not weight until it is convent you could ruin the HPFP. If the light comes back on have it towed to have it fixed, Don't drive it. It is an $8000 fix, and your warranty will not normally cover it. If there is any sign of rust or dirt in this pump it is not covered.
Lynwood

[kab449]

I never had the light come on indicating water on the fuel, but if it did I would drain it immediately. I open the valve to remove any accumulated water every time I change the oil, which is usually at 5000 miles. It is on the inside of the drivers side frame rail approximately under the drivers seat.

[seahunter]

Thanks for the replies. I guess I must be getting good fuel like Keith, since the gauge has never indicated to drain it. I will start to do it periodically though, just to be safe.

[1retired06]

I do once a month and when I change the oil.

[CORattler]

My fuel filter/water seperator gets replaced with a Fleetguard filter every 15000 miles like clockwork. Never had any water in it, ever. I do live in a high desert environment and only get my fuel at high volume stations.
Maybe I'm lucky?
BTW, it's a Cummins. That shouldn't make a difference with this issue though.

[Fire5er]

As mlh said these high pressure fuel pumps are VERY fragile and even a little water in them can ruin them in a heart beat...so draining and checking once a month is cheap insurance IMHO.

[BB_TX]

I have drained mine occasionally. Have never seen any evidence of any water at all. And never had the indicator say so. I would assume you could see any in the bottom of the glass if it were there.
Only use Shell at busy stations when possible. Or other name brand at busy stations when not. I never stop at a no name independent, or even a brand name if it looks to have little business.

[GregN]

Driving a 1997 Ford PSD, 210,000 plus miles on the engine. Not once have I ever drained off any water. I always get my diesel at stations with a good turn around on fuel. Never at a mom and pop that has diesel and have never had a problem.

[seahunter]

quote:Originally posted by GregN

Driving a 1997 Ford PSD, 210,000 plus miles on the engine. Not once have I ever drained off any water. I always get my diesel at stations with a good turn around on fuel. Never at a mom and pop that has diesel and have never had a problem.

That's good to know! I usually always go to a Shell which is on the way to/from the trailer. It is right in front of a Home Depot, so I figure all the work trucks might use the station. I too seem to be getting good fuel, but I am going to drain it tomorrow and see how it looks. Dumb question, but I've never had a diesel before - how evident is the difference between the fuel and the water when looking at it in a jar?

[jlb27537]

In a jar the fuel will float on top of the water. Drain after it sits overnight. Good fuel will have a slight amber color, the water can be between clear to rusty.

Your best bet is just buy fuel from busy stations and drain when you change the oil.

Jim

[1retired06]

I have owned 4 Ford diesels, and I recommend whatever diesel you run, periodically drain the water separator filter.

[JandC]

I am approaching 30,000 miles on my 6.7 and only drained the fuel/water filter once. There was no evidence of water so I have left it up to my mechanic to check it at oil changes. Like others have said, it is a good idea to only purchase fuel at busy stations.