Water in fuel alarm but none in Racors?

[Aerobaticflyer]

I had "water in fuel" alarms go off on my Cummins QSB 390's this weekend but found no water in either Racor unit. Also one engine alarm cleared itself but came back on after a 30 minute run. I only have 80 hours on the engines since a full filter change and annual service. The boat did sit for 3 weeks this time with 1/2 tanks but I'd be very surprised if that contributed to my alarms. Also I ran 90 miles on the fuel in the tanks with no issue until I went to the boat this past weekend.

Anyone have any ideas before I schedule a service call? :huh:

 

[melida]

Hi

I assume you have water sensor under your racor bowl instead of standard plug. Past time if you drained your bowl and tiny drop of water or cumulated contimants stayed on the water sensor. Or may it is damaged and giving you fake message. Check for wiring and electrical circuits.

On the other hand I know from my Volvo Penta's and My dads Yanmar and Cats there is also a sensor on the engine fuel filter. Two years ago while I was draining the fuel from engine filter on my VP I broke the sensor and it was giving red alert while underway altough the fuel was clean, tank is full and filters were new.

Maybe your situation is different from these but I hope they will be as simple and cheap as I had.

Best regards.
Melida

 

[earthmover17]

Missnmountains had this problem last year. Maybe he will chime in. Appears his sensors are at the bottom of the racors and the slightest amount of H2O would set them off.
He installed drains at the bottom of them as I remember.

Jack

 

[missnmountains]

We have had this issue twice. The sensors are on the bottom. Therefore, any, I mean any water or algea will cause the sensors to sound. Both times we had to have the bowls removed and flushed out with some clean fuel to get the sensors to clean up.

We added pep cocks to drain them a little more frequently.

Ken

 

[Aerobaticflyer]

Interesting and I guess I hope the issue really is just overly sensitive sensors as that's a cheaper fix and wouldn't indicate I have a serious fuel problem. I have a diesel guy lined up to check it out and I'm going to accompany him and get some hands on training of all of the issues with working with these filters. It's all new to me.

When I loosened the bowl drain the bowl shield got loose too (appears the plug passes through the metal shield on the bottom of the glass bowl). :huh: I was afraid of getting the drain plug too loose or taking it completely out and not being able to get it back in. The petcocks sound like a good idea if you have to drain these often. As long as they don't allow an air leak. I have heard some say that can be an issue with the petcock type drain valves.

The alarms are going off when I push the starting switches to prime position even before cranking the engines like maybe I'm not resetting the alarm right. I go into the Smartcraft unit and under factory defaults I reset both active and history alarms. Must be doing something wrong. Hopefully the tech will enlighten me.....I'll let you all know what it turns out to be. Hoping for the best.

Thanks everyone.....

 

[tobnpr]

I can't help but wonder why the water sensor isn't mounted up higher- like an inch up from the bottom of the bowl. I don't have them installed, but since the very first drops of water trigger the alarm it sounds "oversensitive" to me...

This will be a good opportunity to learn about cleaning/servicing the Racor. Have the tech show you how to disassemble (easy) and clean the housing. There is a "wear part"- a checkball and seal- that should be replaced when you tear down the filters to clean them. Keep a set of spares on the boat also along with the filter elements. Learn how to replace the filter elements and bleed/ re-prime the fuel system...Be sure to have a gallon of clean diesel available to fill the housings after you change the elements.

I believe Gary posted a thread about petcocks that didn't leak- do a search for it.

I've never had a drop of water in mine in 2-1/2 years (I shouldn't say that...) so I've never bothered with them- although I wonder if they might make draining them a bit "neater".

 

[fwebster]

The petcocks from Parker/Racor usually don't leak. If you buy them from another source, be sure they are for fuel rated, not for air. Most manufacturers also recommend that you insert a 1/4" NPT plug in the open end of the drain valve to avoid leaks of fuel out or air in.

 

[Aerobaticflyer]

Here's an update on my original problem. Mechanic determined there was a little water / sludge in the Racors even though I found none. He drained them, changed filters and installed drain petcocks and tubing from one to the other and that took care of the issue. The tubing is connected to each other so if a leak did develop in a petcock it wouldn't suck in air. Good idea I suppose. I just disconnect the end of the tubing from the filter I'm not draining and vice versa.

Boy these sensors must be very sensitive. At least it should be easier to deal with going forward.

 

[Odyssey]

Guys - I don't have sensors in my racors on my 1995 3116's. I change them out regularly but don't do anything other than replace the filter.

Should I be doing something else?

Randy

 

[earthmover17]

Guys - I don't have sensors in my racors on my 1995 3116's. I change them out regularly but don't do anything other than replace the filter.

Should I be doing something else?

Randy

Randy,
Changing the filters is usually sufficient. Depending on how clean your fuel stays dictates how often you need to drain the bowls and clean them. If the fuel looks clean and pinkish your good shape. If it's dark red maybe time to dissassemble them and clean them.

Jack

 

[Odyssey]

Thanks Jack. Maybe the next time I change them, I'll remove all the fuel and completely clean the unit.

RB