water separator light on even after drain?

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sambo88
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water separator light on even after drain?

Unread post by sambo88 » February 16th, 2013, 6:07 pm

Hi all,

01 Turbo Diesel Rodeo, (260,000km on clock)

I was under the hood earlier for some bloody reason, anyways was looking at the water separator unit and then noticed a wire was unplugged, so I plugged it in, then turned on the engine and the water separator light came on so I nearly had a heart attack and turned the engine off, trying to think how long that wire has been unplugged for (and it would've been unplugged since I bought the car last September and I'm sure it's been unplugged even before I bought the bloody thing)

Anyway, so quickly ran down and picked up a new fuel filter using the misses car and got some diesel for it.

Came home, removed the old fuel the filter, drained the separator. Only diesel was pouring out of the bleeder valve couldn't see no water, a bit of muck but not much. Bled the air, then I went to kick the engine over, the warning light still glowing, so turned off the engine, and begin draining again, each time only diesel coming out (I compared the diesel coming out with the diesel I picked up from the servo in the jerry can for the new fuel filter). Probably did it about another 5 - 10 times, but the darn light is still coming on.

Now, I don't know what the warning bells are for water in the lines, whether its poor performance, black smoke, engine on fire but the car runs fine, doesn't back fire or is sluggish at all, got plenty of power.

So, could one of these sender units go faulty? As I'm leaning towards the previous owner hopefully getting it looked at and the mechanic saying its all good just the senor buggered so I'll just unplug it so you can ignore it (regardless of who has unplugged it, its a pretty bloody stupid way to fix a problem) So I'm thinking I could just purchase a new unit from repco or somewhere and see what happens. But just after some feedback.

Like I said, the ute doesn't run sloppy or have any issues regarding fuel, after changing the filter and draining, and since I bought it I've put about 20,000k's on it since I use it for work every day of the week, would've thought if there was water in it then I would've at least done some significant damage!

Don't know if it would make an effect but I put the 2stroke oil through the fuel too, so I'm going to stop doing that for the next few tanks also see if that stops the issue if replacing the unit doesn't.

mydmax
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Re: water separator light on even after drain?

Unread post by mydmax » February 16th, 2013, 8:02 pm

sambo88
I have a spare filter i bought and it has the following, just went out to the shed and checked in case I missed something.

At the bottom of the filter case there is a hex plastic plug which is the water sensor.

The plug consists of a vertical section inside. This has a float arrangement on it.
In the sealed tube there is a reed switch which is always held open by the magnet in floating collar as it sits at the bottom.
Float doesn't float in diesel because of its specific gravity. Therefore no connection of the two wires to turn on the light.

When water gets in there enough to float the float eg raise it. The magnet is taken away from the reed switch and it makes a contact, turns the light on and indicates WATER.

Yours float may be jammed up the pole by crud or the magnet isn't a good magnet anymore or the reed switch has failed.

If you have the base plug out and let the float go to the top of it's movement (near the circlip) the reed switch should join the wires (test with ohm meter). If the reed switch measure as though it is contacting all the time no matter where the float is the the reed switch is faulty and acting as though it is on all the time.

Jaycar sell reed switches and you may be able to remove the old one and get a new one and silastic it in place in the blind tube. Jaycars reed switches are available in NO and NC, you want one which is open when the MAGGOT is close at the bottom.

mydmax

sambo88
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Re: water separator light on even after drain?

Unread post by sambo88 » February 18th, 2013, 9:24 am

it appears to be a completely sealed unit so I can't really check inside to see if the device is faulty, can't even unscrew the plastic container from the top part!

I'll see if I can source a replacement that looks the same so it can still bolt to the original mounting points and will also be the pump for bleeding.

mydmax
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Re: water separator light on even after drain?

Unread post by mydmax » February 18th, 2013, 8:14 pm

I just put the base back in my spare after the other night.
The two wires which come out the bottom are VERY close together and if the drain has been undone, or the wires moved with vehicle movement they crack the plastic insulation immediately below the white plastic and the insulation shrinks away slightly.
That leaves the two wires able to touch each other and turn on the light although there is no water.

Have magnifying glass LOOK at the wires as they leave the plastic, they may be touching.
A piece of credit card between them with a bit of silastic would keep them apart, saves money too.

Cheers

mydmax

sambo88
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Re: water separator light on even after drain?

Unread post by sambo88 » February 19th, 2013, 6:44 pm

hey mydmax,

Thanks for that, I took it out just before and got the old maglite with magnifier onto it, can't see any crack or any disruption to the wires themselves.

I've priced up a replacement from Isuzu here in Brisbane which I am leaning to purchase, only slight difference is the nozzles and the angle they are on (the one in my truck has them pointing down, this replacement hasn't them putting up on an angle).

I'm planning on buying this part in the next couple days, the only difference is them in how the nozzles are position, my unit has the nozzles pointing straight down but the new one seems to have them facing up on an angle, so I'll either need to buy longer hose to make the length or somehow turn these to point down, but can't seem to work out how I would adjust the angle as there isn't anything to get a spanner on to it?

I've uploaded a pic of the unit (image is from japanese website but exact same oem #) so you can see what I mean
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cmar
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Re: water separator light on even after drain?

Unread post by cmar » February 19th, 2013, 8:08 pm

Why not just swap the bottom bit?
Haven't owned a 2WD since 1982.

sambo88
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Re: water separator light on even after drain?

Unread post by sambo88 » February 19th, 2013, 8:28 pm

Can't get it off, it's tighter than a nuns habit

nilla60
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Re: water separator light on even after drain?

Unread post by nilla60 » February 19th, 2013, 10:41 pm

Sure sounds lie the previous owner disconnected it because it was faulty.

Johnnojack
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Re: water separator light on even after drain?

Unread post by Johnnojack » February 20th, 2013, 10:49 pm

You need a strap type wrench to undo it. If you put the hexagonal aluminium flange in a vice it will lock up, preventing you from undoing it. It has a r.h. thread. I presume your original one has the same flange. You do need to get it apart as I can guarantee the inside needs a good clean. Most people drain them occasionally but never take them apart. When you take one apart that has never been cleaned it will be filthy.

mydmax
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Re: water separator light on even after drain?

Unread post by mydmax » February 20th, 2013, 11:37 pm

sambo88
Sorry mate, the one I was talking about is a bit different to that one.

On yours if you gently massage the ring at the top of the plastic with small hammer it will loosen the grip between the ring and the body. Then you will be able to undo it.

The fact is, as Johnnojack said, it will be filthy inside. Most likely the float has been clogged with crap in between the moving bits and locked it in the up <the ON, position. Wiring and reed switch may be OK.

Just tap that ring and get it off, make sure you wire brush and grease the thread and ring before refitting the ring. None inside though. Wire brush on ring , could be painful.

mydmax

sambo88
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Joined: June 14th, 2010, 5:18 pm

Re: water separator light on even after drain?

Unread post by sambo88 » February 22nd, 2013, 7:25 am

well fellas, thanks for all your help with this bloody thing. I ended up just buying the replacement part from an Isuzu parts dealer here in Brisbane (OEM 8970818143 for anyone with a rodeo and similar issue - $210.00 ex gst) and bought 2m of fuel hose and about 20 minutes later she was all good and the darn sensor ain't showing up on the dash no more.

The new one I bought, if I turned upside down I could hear the float move around. When I drained my old one I did the same thing, heard nothing so it must of been the stuck sensor. I'm sure that would've been a fairly easy fix to do but I'm just as happy buying a replacement part and knowing that it is all good :)

patanga
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Re: water separator light on even after drain?

Unread post by patanga » January 24th, 2018, 3:42 pm

What does the oil seperator light look like?

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