Last time our 2001 F250 7.3L was warmed up we noticed a pooling of liquid under the truck and hubby determined it was fuel. Since today and this weekend is much warmer, he decided to determine where it was coming from. Fuel leak is at the Water Separator Valve.

Can anyone direct us as to what needs to be done? Hubby is an old time mechanic so not afraid to get his hands dirty...but if this is a heavily involved task he may take it to the dealer. We don't know just what all is involved in doing the repairs on this, so advice is requested...thanks a bunch!

 

Fuel Filter Bowl Drain Valve O-ring Kit Viton 3 piece o rings.

You will need to replace the Three O-Ring's to stop the leak. This is common. Especially when Cold because the shrink. But, when no longer playable, leaking occurs.

There are many suppliers here who sell them. DON'T consider using anything but the Viton - they're specifically fabricated to resist hydrocarbons like fuel and oil.

The bottom photo is the Valve itself removed from the rear of the fuel housing.

 

Thanks a bunch for the information and the picture of that valve. Hubby was pleased to see that there are 4 screws (or whatever) that holds it in there...he couldn't see that from the front.

Can these O Rings (by Viton) be found at local parts and/or farm stores?

 

The Rings are MADE of Viton, it is a Polymer rubber. Usually Brown in color. You can get them in the world, but you are better off buying the kit from Riff Raff, or the Diesel-O-ring site. they are not an off the shelf size. I'd show you the Links, but I'm still at work so....... also the Fuel Bowl will leak fuel fast when you pull off the valve, so be prepared.

 

Looks like Diesel O-rings has upgraded to Fluorosilicone. I trust them. And there is an instruction sheet link on the page!


http://www.dieselorings.com/12-001.html

 

Thank you Coax9952 and Paul...I've forwarded this info on to hubby as he doesn't do FB or Forums or Google searching much ;-)

With the Riff Raff and Diesel O Ring sites...I found those thru Google of such, so sent the links to hubby.

 

Whilst snooping around once I found a write up that said that the fluorosilicone was a good choice for O rings that just sit but not so good for applications where parts move on/around them, does anyone else have anything on that?

 

That is true but our drain valves are not rotating at 3600rpm.

The fluorosilicone material is what the biodiesel industry recommends and it also does a lot better job with the additives that are put into the ULSD.

I have been running the same set of fluorosilicone o-rings in my drain valve for over 9 years now.

 

I just changed mine out today. I just went with the O-rings that were already on the new drain valve unit. My original was over 16 years old so when it went today, it was time I guess. I did come to the realization that I needed to add a much longer 1/4 ratchet to the tool box. Talk about a PITA getting in there and getting that thing off and the new one tightened back down.

 

Why did you buy a new 'drain valve unit', you could have just changed out the O-rings, from Diesel O-rings??

 

I purchased the valve several years ago from Riffraff and it's just sitting in my extra parts box so I just put it on.