Warning Alarm for VRO failure? 1995 150 EXEOM

[w2much]

I am at wits end with my Hot alarm going off and hot light lighting up. Been doing this since I have had the engine(4 years). I have recently had the engine rebuilt by a reputable technician in Orange county CA. I am still running premix plus the VRO system to over oil during break in. Actually I am past the break in period but am afraid to stop using both systems (premix and VRO).The alarm sounded both before and after the rebuild always intermittent and always at slow speed. After the rebuild I told the tech that the alarm was still sounding once in a while as it always has. He claimed that the engine was not overheating and that I should get a thermal gun to verify this. I went out today and as usual the alarm sounded several times. I checked the temp which was at about 140 to 148 degrees, so no overheat, that's good to know. Sensors are new on engine, boat fuel system was checked and OK,d. I have even run it on a portable tank to verify the boat fuel system. Today after about two hours running time I only used about 1 pint of oil from the remote reservoir. Does the hot alarm sound if there is an oil delivery issue. Does the hot light light up along with the alarm sounding if there is a fuel restriction? What can trigger the alarm only at slow speed(idle ) if there is no heat issue? and no fuel delivery issue.? Can the horn be tested by itself? I have grounded the tan and tan and blue wires to test the horn and it sounds as it should when these wires are grounded. What else may send a signal? Again, does the alarm sound for oil delivery? I have a OMC prewired binnacle mount control. I will pay the money for whatever the part may be but no technician has yet to either witness or solve the alarm issue. I have read so many alarm issue threads many in this forum some are solved but many just seem to go away without a solution. I appreciate any input and am willing to try all suggestions that are new to me. Thanks.

 

[boobie]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

Two things I can think of and I may be wrong. If you still have the orginal 95 oil tank hooked up, you could be getting false signals from that. Disconnect the wires going to it and see what happens. Second thing, You just may have a bad horn. OMC had probs with those horns back in those days.

 

[w2much]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

Boobie, Thank you for your reply. I have in the past unhooked the remote tank wires to no avail. Is there an OHMs or other test or something for testing the horn? They only cost about 70 bucks , I would prefer to test it if there is a test for it. I have an OEM manual for the motor but the only test that is mentioned for testing the horn is to ground the tan and the tan and blue leads to the block.I have performed that test and of course the alarm sounds as it should. Why would the hot light on the system check tack also light up? You mention problems with the horns , were they sending false alarms? Thank you for your input.

 

[Haffiman]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

Which spark plugs are you using?
Knowing that your engine is at correct temp, have you tried (one at the time) to disconnect the wires from the temp switches to see if alarm still goes off and light on at the instrument?
It might even be the instrument itself that is faulty and triggers the alarm, try to disconnect the big plug at the back.
As long as the oil consumption stays around 2% of your fuel consumption you are OK with the VRO.

 

[w2much]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

Haffiman, I was using Champion ql77jc4 I believe, the technician replaced them with other Champion plugs he said were better and replaced by an OMC or BRP bulletin update at a previous time. Off hand I do not know the #'s,. I was told by another technician that my problem may just be a bad tach (OMC system matched) sending a false alarm. I replaced it with a new (new old stock, not used) one and the problem has persisted. This raises another question . If the big plug to the tach is unlugged is it possible for the alarm to sound? Or the hot light to light? I was told here on a previous post that the tach could not be a reason for the false alarm. Just sayin. Last , is that in the past I have run the engine temporarily with the temp sensor wires disconnected at the bullet connecters and yes the alarm did still sound. Go figure. Think about that. Thank you for your imput I do appreciate it. Keep em coming.

 

[Haffiman]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

If I was to take everything 'told' by others as granted, I would probably be broke long ago!
A faulty tach (system Check) may set off the alarm if the multi plug is in place, but not if disconnected.
Something is setting off your alarm, and does not seem to be what indicated - the temp switches.
It might be the horn that is triggered by a 'micro voltage' (ground) in the harness/sensor/tach wireing system.
It might be the horn that gets triggered by high voltage in the system due to 'failure' in the horn, This may happen even if the horn pass the normal 'grounding' test.
It might be needed to disconnect everything but the horn and start driving. Then add one at the time switches/sensors until problem re-occurs.
It might be a tricky and tiring operation, but you have to be systematic.
When the alarm goes off, does it stop after 1 min but light keeps on?
If not, horn is defective.

 

[w2much]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

Haffiman, When the alarm goes off and then stops , yes, the light will stay on. I like your logic. I have been frustrated to heck each week or sometimes month(during the winter when I do not use the boat much) each time trying a new remedy. Your solution sounds quite methodical and thorough. I do not care to run with no alarm system at all for any amount of time although it seems that may be what is needed. Each time that thing goes off sends shivers down my spine. Is it false or is it for real. Like the boy who cried wolf. The wolf got him in the end. That is why I had to have the rebuild done. The one time I ignored the alarm it overheated and I lost two pistons. Now I find myself in the same shoes (or boat). So the alarm system is by no means a simple system only set by vacuum, heat and volume, all on and off switches. Being intermitant complicates it further. Micro voltage, high voltage and horn failure sound a lot more complicated . How can the horn failure set the alarm off.? Is the horn a common suspect.? as the tach has already been replaced? This does not seem to be a common sensor issue.Thank you again .





/

 

[laderwell]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

you might have a fuel restriction ,setting off your vaccum switch which sets off the alarm when fuel suction hits 7hg.
try running it with a portable tank and see if it disappears. Another way is to hook up a vaccume gage to your fuel line and when your
alarm go off see if your gage stays around 2 or hits 7 and your alarm sounds

 

[seahorse5]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

Your engine is a 1995 per your post and the model number. That one did not have SystemCheck along with the 4 warning lights as that feature was introduced in 1996.

If yours is truly a '95 with the warning lights, then someone did a modification to your motor by using 1996 and later parts and wiring. The oil tanks are different between '95 and '96 also because of the warning system changeover.

Does your motor have the big round red plug for the wiring to boat harness or does it have 3 separate connectors, 2 with 6 pins and one with 3 pins?

 

[w2much]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

laderwell, I have had the fuel system checked. Checked OK by the tech. He used a vacuum gauge. Of course as the problem is intermittent the test was not done while the alarm was sounding. That is the frustrating part. I have tried a portable tank several times and the alarm did still sound. I too considered the vacuum switch but have pretty much discounted it as a cause but then again something may be be odd or overlooked somewhere. New filters, seperater, fuel lines , bulb, removed anti siphon. I even ran with the fuel fill open thinking it was not being vented. Still need help here. Appreciate all suggestions. Thanks

 

[w2much]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

seahorse5, Thank you for your reply, My engine has the big red plug. It was 1996 that the harness was changed by OMC. I purchased the boat used in very good condition a few years ago . The system check tag was still attached to the oil reservoir. I have the tach with the warning lights.Is this the wrong tach? What did the 1995 have as far as warning lights? Was it just the horn on the binnacle mount? What was the difference between the 1995 and the 1996 oil reservoir wiring? Although I replaced the tach with the same one that was in the boat originally the one that was replaced appeared to match all of the other gauges(trim tilt, fuel, amps and speedo). . Just paid a fortune to have the engine rebuilt. The technician is $90.00 away in gas. I don't mind bringing it back to him to fix the harness if that is the issue but need all of the imput I can get before doing so. He claims the problem is in the boat not the engine. If I can fix it I would prefer to do so.I appreciate all replies.

 

[Joe Reeves]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

(Testing Warning Horn)
(J. Reeves)

On VRO equipped engines where the VRO automatic fuel/oil setup is still being used, make sure that all components are connected as required. This would include the VRO pump wiring harness itself, the oil tank wiring, the overheat sensor(s), and if so equipped.... the vacuum switch that is standard to many V6 & V8 engines.

If the VRO automatic setup has been eliminated and has been disconnected properly, and the fuel and oil is being premixed, make sure that the overheat sensors are still connected, and the vacuum switch if the engine is so equipped.

On engines prior to 1984 which have no VRO setup, ignore the instructions pertaining to the VRO components, etc above.

Turn the key to the ON position (Engine Not Running). Find the TAN wire at the cylinder head(s), then ground out the portion of that wire that is part of the engine wiring harness. If that Tan wire connector has the knife type connector where as it is exposed simply by sliding the rubber insulator back, it does not need to be disconnected.

Grounding that TAN wire should cause the horn to sound. If it does not, find out why as that's the only warning you'll receive should the engine overheat or have some portion of the VRO system fail, or have the engine encounter a fuel restriction if it is equipped with a vacuum switch.

********************
(Odd Soundings Of Warning Horn)
(J. Reeves)

Should the warning horn beep constantly when the key is turned to the ON position rather than sounding just a short beep as it should, do the following test.

Remove the TAN wire from the horn. If the constant beeping continues, the horn is faulty, in which case replace it. However, on the other hand, if the beeping stops, something has gone wrong with one of the sensor components at the engine, in which case start disconnecting the TAN wires that are connected to the various components (Heat Sensors, VRO, Vacuum Switch if so equipped, Oil Tank). Disconnecting a unit and having the beeping stop...... you've found the faulty component.

NOTE: The small black plastic horn that has a built in black ground wire...... The TAN wire must be attached to the terminal closest to that black wire. Otherwise weird things will happen.

********************
(VRO Horn Warnings)
(J. Reeves)

NOTE: I retired around 1991/92. Possibly some of the later V4 engines and others may also incorporate a fuel vacuum switch that would enable a fuel restriction warning to sound as mentioned below, an unknown factor to myself.

1 - A steady constant beep = Overheating - The V/6 engines, possibly some others, have a fuel restriction warning which is also a steady constant beep.

2 - A beep every 20 or 40 seconds = oil level has dropped to 1/4 tank. (Late model engine = Every 40 seconds)

3 - A beep every other second = VRO failure, air leak in oil line, oil restriction, (anything that would result in a lack of oil being supplied to the engine).

NOTE - If the warning horn is the black plastic (overpriced) three wire type horn, the warning horn should beep once when the ignition key is turned to the ON position. If it does not, it is either faulty or someone has disconnected it (a stupid move!). At any rate, if it does not beep which indicates that the horn is non functional, find out why and do not run the engine until the problem is corrected.

 

[Haffiman]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

I'm beginning to suspect that a conversion kit may have been used between the original engine harness and the boat system check harness and instrument.
technically correct if remembering right, but has to be combined right as well!
If engine and VRO oil tank are pre systemcheck, do NOT use the big contact into the rev counter, but use the separate grey for the rev counter function and not the systemcheck plug for the alarm system into the tach.
As for the alarm horn, you may use the system check horn, but will then loose the different beeps telling if no-oil, low-oil or temp alarm.
All this due to the system check engine harness has separate alarm leads for different functions where as the non-system check use one lead to the horn and the different alarm signals are controlled by the different switches/sensors on the engine.

 

[Haffiman]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

PS:
If at 'any cost' buy a system-check engine harness and change. (Perhaps from a junk yard?)
If 'acceptable', get a pre system check alarm horn and sender in the oil tank, or pull a separate wire from oil tank to the corresponding pin in the big plug at the back of the system check instrument.

 

[w2much]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

So It all starts to make sense .I checked my title and the boat is a 1996, the engine 150 EXEOM is a 1995. You all have provided a wealth of information and are making sense of an annoying and dangerous situation. I will need time to absorb all of this before tackling it. I will repost when I have more to add. Thank you all for going the extra step with me. From Malaysia, Florida, and who knows where else to San Diego. Much appreciated.
PS Joe Reeves In paragraph 4 or sentence 4 you mention " some portion of the VRO system fail". Does the alarm sound if there is no oil being pumped. In my first post I mentioned that almost no oil was consumed yesterday. I am running premix because of the uncertainty. It seems with the two different systems (1995 and 1996) my alarms may not work according to seperate beeps vs one long beep. This being noted by Haffiman "seperate leads for seperate functions where as the non system check use one lead to the horn and the different........................" Post #13. So when my alarm sounds I may not be getting oil although the hot alarm is activated. Two sytems not matched.

 

[clanton]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

The 1995 red plug engine harness has one tan wire going farward to control to operate the horn with the logic on the back of the horn. The logic reads different ohms from the sensors sound the different beeps, to indicate which sensor is sending the signal.

The 1996 with 4 or 5 black connectors has 4 tan wires going farward to the tach, logic in tach, signal goes to tach, horn beeps, red light comes on and stays on until key off. Horn only beeps one time, and auto stops.

The 2 horns are different, and the oil tank is different.

If your control harness has the 4 tan with marker wires back to the engine, you will have to splice these to each sensor wire to the correct tan wire in the control harness, or buy an engine harness to make the System Check work.

Diode location will need to be check for proper location in splices.

 

[clanton]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

I have the wiring diagrams, I can email to you. Send email to PM.

 

[w2much]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

So I had the chance to get up under the console and yes there is a system check adapter spliced into the pre system check harness.
So if my understanding is correct the different alarms, steady, or on off on off would not function. Instead I would get only one type of alarm for whatever the problem is. One system has tach logic the other horn logic. My system check tach is irrelevent as far as the warning lights are concerned? What type of tach was for a 1995 pre system check? Did it have warning lights or just the alarm at the horn function?
It is in the past now but was my warning sounding due to OMS(VRO) failure or was it overheat that killed my engine?
Then again is my alarm sounding now due to VRO(oms) pending failure? It is not overheating but the alarm is sounding. Perhaps it is working correctly for all of this time just speaking its own language? Seems to make sense?

Clanton, Thank you . Yes I would like to see the wiring diagrams. You may PM me.

 

[w2much]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

Could someone pleas refer me to a VRO disconnect thread. I think I shall disconnect the VRO and alarm to start with. Thank You.

 

[Haffiman]

Re: Warning Alarm for VRO failure? 1995 150 EXEOM

Just dis-connect the VRO oil-hose from the pump and plug the pump side with a screw or similar. (to prevent from sucking air).
Disconnect the 4-lead wire plug from the VRO. (stops false alarms).
Disconnect the leads from VRO oil tank to engine.
Mix 2% TCW3 oil in the fuel and run!