Optimax low oil warning message on gauge

[whackywoody]

Hi, I'm looking for help please and this is the following scenario

I have a 2000 digital optimax and have the low oil warning message on gauge and initally read 0.0 gallons level but now won't give a level reading just a low level warning (AL). There is a reservoir tank under the cowl and a seperate tank at the front end of the boat. I had the gauges working without engine running and it had an oil level reading (3.8 gallons) and also had the engine running but without gauges. Since then I have disconnected and reconnected reservoir oil pipes and electrical connection (main cowl connection to boat harness) as the remote tank has been relocated in the boat and I have now got this fault. Both oil reservoirs (under cowl & remote tank) are full to the brim. I have done the following to try and diagnose the fault:

1.) Had I got the 2 x oil pipes (reservoir and crankcase) mixed up? As there are several connections and some sections of blue stripe missing - Think I have disproved this as the under cowl reservoir tank filled itself and overfilled during the manual prime process. Also the remote tank is pressurized when cap is removed suggesting the back pressure from crank case is doing what it is supposed to do?

2.) Is oil pump working? Removed an outlet pipe (going to piston cylinder) and during priming process could hear the pump clicking and see oil pulsating from pump outlet pipe going to cylinder (which I had temporary removed). However when engine running on idle nothing came out of oil pump outlet pipe and couldn't hear pump running but engine was ran for a maximum of 30 secs as I doin't want to damage it. With the oil / petrol mix ratio (now set to break in as I had primmed)I'm not sure how often the pump will disperse oil when engine running, would it take several minutes?

3.) Wiring harness under cowl for remote oil float connection - This is fool proof and cannot be connected wrong way around however it may have got water in the connection prior to been reconnected although it was squirted with wd40. I am reluctant to look at this connection as its buried and its a terwat to get to but if I disconnected from main harness would this rule in or rule out to the remote oil tank?

Sounds like a can of worms but I am looking for suggestions as I am trying to diagnose if I have an oil pump failure or a remote tank failure or something else. Failing this would I could pay someone to do a DDT hook up, might be the best option?

I have looked at the manual and it doesn't tell me a great deal!

[Turbodiesel]

Check the float in the main tank is not stuck down, its easy to get the thing in the wrong way round.

[whackywoody]

Originally Posted by Turbodiesel

Check the float in the main tank is not stuck down, its easy to get the thing in the wrong way round.

Hi Rob, never removed the floats from remote tank but did have tank under cowl on its side as I removed it to get at the gear shifter cables. However I will check both floats by manually putting float height at full position on both tanks to see if it clears faults

Thanks

Gareth

[Jizm]

Originally Posted by whackywoody

Hi Rob, never removed the floats from remote tank but did have tank under cowl on its side as I removed it to get at the gear shifter cables. However I will check both floats by manually putting float height at full position on both tanks to see if it clears faults

Thanks

Gareth

Good shout. It's what I would try first....

[whackywoody]

Thanks J and Rob,

I have taken your advice and have found the following,. Forgive me for sounding a bit thick but I'm not an electrician

1.) Oil float in remote tank checked with voltmeter to read resistance in ohms and the voltmeter set at 20k (not sure what that means) and at float position empty the resistance read 0.24 at empty and 0 when full. So I am happy with this and believe it works

2.) Oil float in reservoir is a different story and would not read any resistance at full or empty (submerised in oil and out of oil). I even tried the different settings on the voltmeter (2K, 200K, etc) and dead. Also the connection was very badly corroded and even when removing the connector and cleaning the end of the wires it made no difference. So I'm guessing that this is the problem and needs to be replaced? If it is any idea where I can get one from?

If it is the float switch this is because I removed the engine cowl (for security reasons) and put a plastic bag over it which had a hole in it

[Jizm]

Originally Posted by whackywoody

Thanks J and Rob,

I have taken your advice and have found the following,. Forgive me for sounding a bit thick but I'm not an electrician

1.) Oil float in remote tank checked with voltmeter to read resistance in ohms and the voltmeter set at 20k (not sure what that means) and at float position empty the resistance read 0.24 at empty and 0 when full. So I am happy with this and believe it works

2.) Oil float in reservoir is a different story and would not read any resistance at full or empty (submerised in oil and out of oil). I even tried the different settings on the voltmeter (2K, 200K, etc) and dead. Also the connection was very badly corroded and even when removing the connector and cleaning the end of the wires it made no difference. So I'm guessing that this is the problem and needs to be replaced? If it is any idea where I can get one from?

If it is the float switch this is because I removed the engine cowl (for security reasons) and put a plastic bag over it which had a hole in it

Yep that's your problem and Rob should be able to sort you out with a new one.

[jambo]

Originally Posted by Jizm

Yep that's your problem and Rob should be able to sort you out with a new one.

Sorry to maybe put a dampner on things. But I had same problem with my 1997 150hp V6 2st renewed the float cap assembly on the internal resovoir and it still flashed. Check that there's not an internal oil sensor on your Opti as there is on the 2st cause that could be your problem. Also have you checked that you are actually burning oil is the level going down because if not hen it could be your oil pump thats causing the problem. Sorry but all worth a check.
Cheers
B

[whackywoody]

Thanks J,

I assume there is an inbuilt float / magnet in the tank as from the photo (earlier post) the sensor is just a reed. However I did test the reed/switch when fully inserted into reservoir (which is full of oil) and when fully removed from reservoir and no resistance for both readings. So I think its either the float that is stuck or sunk to the bottom or the float switch is fooked. I will test the float switch again tomorrow with a magnet and that should confirm my theory.

Jambo, thanks for the points and I will bear in mind but there is definitely an issue with the float so I will address this first

Thanks lads

[Turbodiesel]

The other thing to try would be go into the gauge calibration and switch off the Boat oil tank (go to the setting that says not installed) that way you can identify is its the boat tank or the engine tank. If it carries on playing up you know its the sender on the engine.

[whackywoody]

Ok Rob, I will try that tomorrow. Just tried the sender with a magnet and I am pretty certain it's dead. Have you got any of these senders in stock?

[Jizm]

Originally Posted by whackywoody

Ok Rob, I will try that tomorrow. Just tried the sender with a magnet and I am pretty certain it's dead. Have you got any of these senders in stock?

I've got a used bottle complete with sensor if not.

[whackywoody]

Hi J, I ordered a new sensor off Rob on Wednesday. However I don't know if the float is ok yet so may need that bottle and sensor off you

I will keep you posted

Gareth

[whackywoody]

Fixed it, it wasn't the float sensor after all! The pin had backed out of the connector on the main harness under the cowl.

Boat project is now nearly ready for a sea trial so I should update my project page

Thanks everybody for your help/suggestions!!!