OMC VRO Pump

[MrTuna]

I own a 1992 Montauk w. a 1992 90HP Johnson. I was out on the water today trolling for a majority of the morning. When I went to leave the grounds I advanced the throttle to approximately 4500 RPMs and the motor cutoff. Unfortunately I did this 3 times, before I noticed that the oil tank was empty on the boat. I then shut the motor off. I was lucky enough to get oil out on the water from another fisherman. Obviously it goes without saying that my low oil buzzer is not connected. My main question is whether or not I did damage? I know some of the newer motors recognize that there is no oil and therefore shuts the motor down. I was wondering if anyone familiar with this particular motor would know if that is a functionality of it. After the oil was added I ran the boat for the remainder of the day. All said and done it ran for approximately 30 mins at 4000RPM's and almost 3 hours at 1000 RPM's (I was trolling again). I haven't heard any knocking, but am wondering if trouble could possibly be around the corner, or perhaps the motor was designed not to operate under those conditions and knew to shut itself down. Any feedback would be greatly appreciated. Thanks Chris

 

[TxShorty]

Re: OMC VRO Pump

'Warning Mode' shouldn't completely shut the motor off, but instead it limits motor RPM to less than 2500. Sounds like your motor was trying to seize, and may have some damage in the cylinders. A compression check would be in order at this point.....

 

[MrTuna]

Re: OMC VRO Pump

Sorry about that, to be more specific the boat would come close to stalling. But if you pulled back on the throttle it would stay running. I didn't know there was a "Warning Mode" for that year. Even if the compression checks out, is there potential for other damage that can't be assesed without finding out the hard way ?

 

[MCM]

Re: OMC VRO Pump

When you say the motor cutoff do mean it lost power as in the S.L.O.W feature TxShorty referred to kicked in or did the motor shut down completely? At the very least the motor was probably overheating, since you were able to let it cool off and then continue on your way might indicate you got lucky but I think as Tx suggests a comp. test may be in order.

 

[MrTuna]

Re: OMC VRO Pump

I am not overly familiar with the ins and outs of the motor. But the reason it slowed and still ran was because I backed off the throttle. The first time that it happened, I didn't have that reaction and it stalled. The second and third time I sensed it was preparing to shut off, so I backed off and the motor remain running. I am in NJ and the water is cold right now...approx 56 degrees My stats are out, therefore that cold water is constantly flowing. I wonder if maybe this helped the situation.

 

[andy6374]

Re: OMC VRO Pump

Talk about a close call

 

[MCM]

Re: OMC VRO Pump

I would stongly recommend getting an OEM service manual if you haven't got one and becoming familiar with the motor in order to avoid costly repairs also running the motor without stats can potentially do as much damage as having them in and not working, there's a purpose for them being there, its to keep the motor from running too cool which OMC motors don't care for any more than running hot.

 

[MrTuna]

Re: OMC VRO Pump

I ran a compression check today and on the port side two cylinders I read 110 lbs each. On the starboard side I read 115 and 120. I believe this is a fairly good compression reading. Any thoughts ?

 

[Solittle]

Re: OMC VRO Pump

Compression is just fine. You may have lucked out.

 

[rodbolt]

Re: OMC VRO Pump

but you do need to check the warning system. SLOW wont trigger with an oil alarm.<br /> you should have gotten a low oil warning for 30 min or so before the pump gave the NO oil warning, appearently neither worked. when was the last routine maint check of the alarm system ?<br /> the 92 model, if rigged with 92 stuff, had a horn that self tests. does it still self test when ya turn the key on ?

 

[MrTuna]

Re: OMC VRO Pump

Yes, the alarm does self test. As a matter of fact when I bought the boat the stats were frozen and it would trigger the alarm so I know the buzzer itself works. However, its quite evident that the low oil alarm doesn't work. Any idea what color the wires are ? its quite possible they may have been disconnected by the previous owner. I am thinking if the sending unit was bad in the oil tank it may have kept triggering the alarm, which could have led the previous owner to cut the wires. One thing I noticed today is that the priming ball at the oil tank has never regained its full hardness. The motor is definately burning oil now, but for some reason the ball doesn't get as hard as it used to. I wonder if there is possibly air in the system ?

 

[Mark42]

Re: OMC VRO Pump

Suggest you disconnect he oil line at the motor and pump the bulb until a quart of oil is passed, then reconnect to motor. This will ensure that there is no air in the hose or primer bulb. Then run on a portable tank with a 50:1 mix until you are sure the oil pump is working 100% and the primer bulb is hard again. It wont hurt to run with both the oil tank and gas/oil mix, but if the pump is not working well, there can be damage done if you don't take the above precautionary measure.