Yamaha 200 HP '92 Low Oil/Level Sensor on.

[monoki]

Gents:

I have a relatively simple problem but difficult to troubleshoot.

Assets: I have twin 1992 Yamaha 200 HP counter rotation 2-stroke precision blends on my 1992 Grady-White Sailfish Sportbridge 252.

Problem: The port side Low Oil/Level Light is on constantly. Mechincally the twins run perfectly and only at inexplicable times does the warning beep drop me to the 2000 RPM level.

I've check the oil reserve sensor and pump; the integral oil tank and oil level sensors and the ECMs. I swapped the ECMs, starters, intergral oil tank, and oil level senors between the port and starboard. Mechanically, things look really good. I even put on new fuel filters and sparks in to address the ethanol issue.

Mechinically (I think), all's fine. I took the boat out 70 miles worth on the Chesapeake this weekend. Aside from the warning light being on constantly and, only at times, the Low Oil/Level warning sound triggers and forces the engine to drop to 2000 RPM before I can do anything, things ran well. Engines cool, oil being blended properly, decent fuel efficency and plane.

I'm a good troubleshooter, but this has gotten the best of me along with two other mechanics.

Any thoughts?

Semper fidelis,
Chris Monoki

 

[rodbolt]

Re: Yamaha 200 HP '92 Low Oil/Level Sensor on.

when was the last time you changed the oil filter on the remote oil tank?
a restricted filter will result in low flow and at higher speeds the oil consumed can be more than the speed it can be transfered.
the result is it will run fine for 10-15 min then go into speed reduction and then after idling/low speed use its fine again.
next time the horn goes off carefully inspect the engine oil tank level and listen for the transfer pump to run.
if the trim sender is failing it can inhibit oil transfer as well.
which light is lit constantly? if its the low remote yellow or middle bar on later tachs then hunt for an open circuit on the remote tank switch and wiring, if the remote is low or the circuit open no oil transfer will occur.
the manual switch can overide the low remote tank switch and trim sender and you can transfer oil manually.
the key must be on to use the manual switch.

 

[monoki]

Re: Yamaha 200 HP '92 Low Oil/Level Sensor on.

Rodbolt:

Just the man I was hoping to respond to my concerns. And congrats on the certification. Saw your photo...yep, just as ugly as I thought.

The light that is constantly on is the port side low oil light. In other words, the red arrow. On the starboard side, the black arrow on full oil is on.

Yes, I do hear the reserve pump transfer oil to the integral tanks on shut down. Admittedly, I'm not 100% sure both are working, but I'm pretty sure since the oil level in the both integral oil tanks were full after 70 miles of run.

I HAVE NOT inspected the reserve oil filter, but I will definitely check. However, I did swap the sensors between the reserve tanks and yet the port light is still on.

The trim sender is definitely a possibility, but I don't know how to check for that. Taking notes of what's occurring, I did notice that if I trim out (maybe too much?), there's a greater chance that the warning buzzer will go off and I'll drop to 2000 RPM.

There were at times that I would run at 4000-44000 RPM without a hitch...maybe a straight half- to full hour. The short times I've run at WOT (maybe two mintues per) about 50% of the time the buzzer will go off and I would drop to 2000 RPM.

The previous owner had the same problem and he had a mech look into it to now avail. (search captrich regarding 200 Yammies and you'll see his posts). The conclusion he and the mech had was that the sensor was on, but all was well, and answer that's not satisifactory with me. But even he had a good trip from Palm Beach, FL to the Bahamas (about 56 miles one way) without a hitch.

The fuel filters I did switch to 10 microns to address the ethanol issue. I'm filling the tanks with Ring Free and am using the proper two-stroke Yamilube. The sparks are new; the coils are good. The integral oil level sensors appear clean and in good working order. The ECMs look friggin' brand new, clean and all wires looking pristine. The starters are great as well.

Aside from the low oil sensor, the only other problem I having is loseness in the steering (Star Bright). Filled up with hydraulic fluid, I don't think there's air nor leaks in the lines. But lots of play.

Thanks for the help Rodbolt, and I hope we can troubleshoot this down.

S/F
Chris Monoki

 

[monoki]

Re: Yamaha 200 HP '92 Low Oil/Level Sensor on.

One other thing, the manual switch does work and I have used it only to fill the integral oil tank more than the fill line. The purpose was to make sure the manual switch on the ECM was working. On the port side, I did notice that it is slower to fill than on the starboard side.

S/F
Chris Monoki

 

[rodbolt]

Re: Yamaha 200 HP '92 Low Oil/Level Sensor on.

slower to fill than the stbd? its time to replace the filter on the remote tanks and check the pump voltage.
if the engine oil pump can use oil faster than the transfer pump can transfer you get those symptoms.
at or near wot your engine will use 20 gallons an hour, 10 gallons in 30 min, the engine oil tank holds about a quart. at a rough 14 ounces for every ten gallons it will take 30 min or less to trigger a low oil alarm if the transfer is restricted by anything.

if the money is right I have been known to make house calls .
all mechanics can be bribed by cash

 

[monoki]

Re: Yamaha 200 HP '92 Low Oil/Level Sensor on.

Rodbolt:

You're in Kitty Hawk and if you're we up here, I would be more than happy to pay you your due. Perhaps a series of phone calls as I do the work myself would suffice.

Before the weekend, I will check the reserve oil filter and the pump. I'll try to isolate the problem by first cleaning or replacing the filter. If I still have problems, then I will switch the entire reserve assembly between port and starboard.

All this said, the low oil light is constantly on despite have full oil in both the reserve and intergral tanks and what seems to be proper transfer. Thus, I wouldn't be surprise to learn the all's well and yet that damn light is still on and the warning buzzer inexplicably goes off.

S/F
Chris

 

[rodbolt]

Re: Yamaha 200 HP '92 Low Oil/Level Sensor on.

if with all the swapping you have done the light still triggers with the engine tank full you may have a bad harness or a loose ground,
if the engine oil sensor becomes disconnected it will set the alarm.
the switch on the engine oil tank provides the ground path for the ECU oil controler for pump on,pump off and low level.
a ground on the blk/red wire will set the oil alarm, look for any chafed spots.
however if the alarm is on it should be transferring oil creating an overflow of the engine tank.

 

[monoki]

Re: Yamaha 200 HP '92 Low Oil/Level Sensor on.

Rodbolt:

None of what you said is occuring. I haven't experienced nor obverved an overflow. I've checked all the wire from the oil level sensor to the ECU; I think all the wires at least on the outboard are good...look good, good connections. The wires by the console is another story; I have a bird nest there.

No matter what, the low oil light is always on. Yet mechically, it appears everything is in working order. At different times the low oil sensor/buzzer goes on and drops me to 2000 RPM. The times that happens are different and in no recognizable pattern, except maybe when I'm trimmed out. Even with that I'm not sure.

I'm going to check the oil reserve pump for clogging, etc., because, as you have mentioned before, it might be that the pump isn't working well (voltage) or there's something keeping flow at a rate the outboard demands at higher RPM.

I'll give you an update as soon as possible.

S/F
Chris