Oil buzzer

[Robintx2]

I will try and keep this short. I bought a used boat. It has a 150hp Nitro EFI engine. It would not start. I fixed that problem the tank and hose were bad. I cranked the motor and it ran fine. i got it up to 5000 rpm's and the tell tell was flowing strong. My problem is i cracked the cap on my oil reservoir under the cowen. I didn't realize it. I started the engine and the oil buzzer started beeping. I replaced the cap and connected it up and the buzzer still beeps. I disconnected the wiring to the cap and it still buzzes. Does that mean the module that the cap plugs into has gone out. I read some threads on here about priming the oil pump. I can't find them now or I would have posted on that thread. Any suggestions from anyone.

 

[Maxz695]

Re: Oil buzzer

There should be a bleeder screw on the pump. Open it and turn the engine until you se oil flow then close it. Also the float sensor in the tank may have an issue.

 

[Robintx2]

Re: Oil buzzer

I did loosen the screw until oil came out. Are you talking about the float in the new cap. Thanks

 

[Faztbullet]

Re: Oil buzzer

I disconnected the wiring to the cap and it still buzzes.

Air in oil pump will not cause beeping as no sensor to monitor it. it sounds like oil module or gear may have a problem...

 

[Robintx2]

Re: Oil buzzer

Is there anyway to check the module.

 

[aussieflash]

Re: Oil buzzer

Also make sure all cylinders are firing.Oil sensor has 1 wire connected to coil connection at switch box(mine is on #4 cylinder).It measures pulses.If that cylinder misfires for any reason,your oil alarm will sound.May have to pre mix till you find problem.
Your Merc Manual will have all test procedures for oil alarm.

 

[Robintx2]

Re: Oil buzzer

Thanks aussieflash. I want to Rule
out everything before I buy a new module. Thanks again

 

[Robintx2]

Re: Oil buzzer

Aussieflash I did get a compression test on the motor. He did check the cylinders and they were getting fire. I ordered a buzzer module that is about the only thing left. It is getting oil. It is smoking the same as it was when it was running fine. I hope the new buzzer module fixes it. Thanks Robintx2

 

[aussieflash]

Re: Oil buzzer

The pump rarely breaks down,9 out of 10 times its the sensor/module/wiring etc.Let us know how you go.

 

[Robintx2]

Re: Oil buzzer

I got my oil alarm module in today. still has the oil buzzer beep. Not sure what to do next. I am thinking it might be cheaper just bypassing the oil pump and just mixing the oil. It is smoking so I know it is getting oil. Don't want to start replacing more parts. I guess it is either bring it to the shop or by pass the pump and just mix the oil myself. Any suggestions or ideas?

 

[wn6ngp]

Re: Oil buzzer

I was with a friend at the coast and his buzzer was going off. The problem was that the float switch down inside the oil resovoir was broken. We could stick a screw driver down into the tank and touch the switch and the buzzer would go off. For that trip we just traced the wires to the oil tank and disconnected them. Ultimately, he had to remove the oil tank and fix that switch.

I did not realize that there were other more sophisticated sensors that actually detect if oil is getting to the cylinders and those can set off the buzzer too. This was just a simple oil level indicator and it was OR'd with the overheat switch.

I guess I'm an old guy. I still think automatic transmissions are just not reliable. I've always been fearful of those auto oil injection things but mine has always worked fine on my 90hp. It just scares me to think about what happens if oil stops flowing.

don

 

[Robintx2]

Re: Oil buzzer

Ok had a mechanic come out and take a look at it. Said it was not circulating water and that the oil buzzer sound would turn in to a hot buzzer alarm after a few minutes. So I had him go ahead and find out what the problem is and fix it. When he dropped the lower unit the impeller was all bent up and one of the blades was almost gone. The water pump housing was scared up and looked like it had melted in some spots. He bought a new water pump and impeller and all the o rings and parts to replace it. We will see tomorrow if this is the problem. But just looking at the water pump and impeller I think this is it.

 

[wn6ngp]

Re: Oil buzzer

interesting, well that is consistent with our observation that the hot head sensor and oil level switch are tied together making an "or" alarm.
It really is unacceptable for them to do it that way. I guess its considered a very gross warning but it would be so easy to have separate warning signals.

Do you have a water pressure gauge? I would guess it would show a problem. I replumbed my boat speedometer as the water pressure gauge and have become a water pressure watcher especially when I go salt fishing given the sand, shell etc.

I think your problem is fixed.

don

 

[Robintx2]

Re: Oil buzzer

Wn6ngp I think your right it is an or alarm. But I did still get an oil beep after the water pump was replaced. I was still pumping oil and it was pissing good. So he decided to check the temperature sensors and they were corroded. He cleaned them and put them back in. Still a buzzer. So he disconnected brown and yellow wire and the oil beep stopped. He said that the wire did not need to be hooked up because I didn't have a temp gauge on my dash it was sending a signal and getting an alarm because it was not receiving the signal. Not sure what to think about that. But it stopped beeping and it is burning oil. I think after seeing the temperature sensors I think it was a temperature problem. The water pump was fried. The impeller was all messed up. Anyone else run into something like this I go along with Wn6ngp that it is an or signal. Oil or temp. Thanks

 

[Dukedog]

Re: Oil buzzer

Don't know exactly what ya got goin' on with all tha buzzers but something is amiss. Tha oil related warnings ALL go thru tha module to produce a "oscillating beep only" and has absolutly no connection to tha heat warning other than they use tha same "buzzer". Sounds like you might wanna make sure tha heat warning circuit is up ta snuff if tha pump was gone and you wern't getting a solid beep warning...jmo

 

[wn6ngp]

Re: Oil buzzer

I was wondering the same thing. On my old school carbd motor there are 2 switches, overheat and low oil in the resevoir. they are tied together so you have to trace things out to figure out what is really happening. Just because I'm cautions I mounted a separate temp sender onto the head with a real temp gauge so I can actually watch the temp.

your motor is a more sophisticated motor, fuel injection etc and must have other sensors that it watches. I would think (hope) that given this extra complexity that there would be a way to tell the difference between the different failing conditions. Its bad enough that oheat switch and oil level are tied together. Like duke says, oscillating sound and solid sound would mean different things.

73- don

 

[Dukedog]

Re: Oil buzzer

They ARE NOT tied together at all no mater how new it is. If they are something is outta whack!......................Those two items and water in tha fuel (efi only) are tha only things monitered on just about anything other than tha dfi/opti and/or smart craft systems......

tx2. What motor ya got that has a Brown/Yellow wire? Just never seen that on a normal 2.4/2.5. Temp for a guage should be solid tan and heat warning should be tan/blue?

 

[Robintx2]

Re: Oil buzzer

They ARE NOT tied together at all no mater how new it is. If they are something is outta whack!......................Those two items and water in tha fuel (efi only) are tha only things monitered on just about anything other than tha dfi/opti and/or smart craft systems......

tx2. What motor ya got that has a Brown/Yellow wire? Just never seen that on a normal 2.4/2.5. Temp for a guage should be solid tan and heat warning should be tan/blue?

I will have to look again but the wire colors were the same on the temp sensor and the alarm module. I have a 1994 150hp Mercury Nitro EFI

 

[Robintx2]

Re: Oil buzzer

Dukedog you are right they are tan/blue. But the one coming out the top sensor and the one on the new alarm module I got is also tan/blue.

 

[Dukedog]

Re: Oil buzzer

Tha one on tha "port side" with tha other two tan/black wires is for a guage. It plugs into tha tan and/or tan/blue that is exposed (like tha trim wires) on tha MALE end of tha harness coming from tha boat. Tha one on tha "starboard" side can be a tan/blue in a plastic sleeve. It should be terminated on a small plastic term strip with a tan/blue in tha female (engine) side harness.......