150 Yamaha Voltage Regulation

[edgutgesell]

I have a 1987 150 Yamaha. This past fall I had an oil injection problem where the oil level sensor in the oil tank on the engine would not cut off the pump in the large tank causing the tank on the engine to overflow. This caused smoking and high oil consumption. The problem has been resolved by replacing the oil control module on the engine. It was pure luck that I didn't burn up the engine because the red low oil warning light (incandescent)was burned out, and I checked the large tank just before the tank was totally empty. Another mile and there would have been didaster!! I would like to replace the incandescent warning lights with light emitting diodes (LED'S)<br /><br />My question is:<br />While running, the voltage meter at the console shows a voltage above 12.6V (about 14+ volts)and drops down when idling. That voltage seems to be unregulated. Are the voltages from the oil control unit regulated and if so, at what voltage? LEDS are voltage sensitive and higher voltages decrease their life span. If the voltages out of the oil control unit are regulated and put out a steady voltage, then I can design the LED warning <br />circuit without adding a voltage regulator to my <br />circuit design. I worked as an electronic engineer in the past, but my knowledge of outboard engine electronics is pretty poor. LEDs can last about 10,000 hours which means that if I design it right, I won't ever have the burned-out <br />bulb problem again!!!

 

[rodbolt]

Re: 150 Yamaha Voltage Regulation

led's willwork<br /> its got a regulator, but like all altenator products it actually works at about 14.5 to14.8 volts at WOT. it takes electrical "pressure" voltage to move the electrons off the battery plates. if all you put out was 12.6,standard battery voltage, it would never recharge a battery until the battery capacity fell below 12.6. there are plenty of LED's that work off 16 v. radio shack has a bunch. just remember in all yamaha circuits "low" lights the light. all circuits are ground switched. but with regular maint like the service guide says that problem would have been caught at the service intravel and the alarm,if it actually is still operable, will sound with out the light. the speed reduction mode, if RPM is above 2500 or so, will work without either lamps or horns. a cheap lesson ya learned. test the oil and overheat audio and visual alarms at the scheduled 200 hour OR once per year intravel. just like the book says <br />once the red light,alarm or speed reduction turns on you have about 20 min of oil before its dry. when was the last time the remote oil filter was changed? if its clogged or the pump connections are bad it can lead tomodule failure. seems the pump can draw more than the module can dissipate.

 

[edgutgesell]

Re: 150 Yamaha Voltage Regulation

Rodbolt, thanks for the reply,<br /><br />The entire oil injection system is working properly now. (I hope!!!) <br /><br />I don't think that I described my question properly! I realised that the voltage increase as the engine rpm's increased was to facilitate charging the batteries. I wondered if that increase is reflected throughout the Yamaha electronics or if there is further regulation at the oil control unit to make it operate with a steady +12V. If the oil control unit is further regulated, then I could design my LED unit without adding a low dropout voltage regulater and just use the indicator lamp output. It seems to me that there must be further regulation because the incandescent lamps are rated a 12.5V and if the voltage at the lamps increased to 14.5V, they would be continually blowing. I understand that the unit operates the pumps, lights etc. by establishing a ground circuit. I would have answered my question myself if my boat was in my back yard, however it is about 110 miles away in South Jersey so I can't get my voltmeter out and check it. Buying 16V LEDs at Radio Shack or elsewhere is too easy a solution. What else would I do with my spare time in the middle of winter?

 

[chuckz]

Re: 150 Yamaha Voltage Regulation

Actually LED's are current sensitive, the voltage drop across them is constant, you can use this to your advantage. Take a simple three pin voltage regulator and configurate in the current mode. No ground is needed and it can be wired in series with the voltage supply. A cheap 5V regulator can take an input voltage in excess of 30 volts. Very reliable and fewer components than setting up a constant voltage source.

 

[Silvertip]

Re: 150 Yamaha Voltage Regulation

Don't make a problem where you don't have one. Electronics, whether its your radio, locator, pumps, or the electronics in or associated with your engine are designed to operate in a "voltage range" (about 12 - 15.5 volts). Because they are stamped at 12.5 volts doesn't mean they will burn out at 12.6 volts. If that were the case not a car on the road would have functioning lights or electrical components. Fact is your electrical system is perfectly safe at 14, 14.5 and even 15 volts. Higher than that is where things can get testy. In your case this bulb simply burned out or the filament broke due to the normal shock and vibration in a marine environment. If you happen to have a battery switch and you switched it with the engine running you can spike the system to where damage can occur. Replace the bulb and you may never have the problem again. Add a warning buzzer that works in conjunction with the light. Had the light been working you may not have seen it anyway and would have had the same problem. In your case it was another problem that alerted you to the light problem. The module failure was also not due to overvoltage but rather it simply failed. Why? Who knows -- stuff happens.

 

[rodbolt]

Re: 150 Yamaha Voltage Regulation

when that motor was originally rigged it had the horn and the light. the yelow lamp should have lit indicating the remote tank was low. the red lamp illuminates when the engine tank is low. under normal circumstances if the yellow is lit the oil pump wont transfer. red takes precedence over yellow when the engine tank is low. when the module activates the red light it also activates the horn and the speed reduction. all of this can be avoided with periodic maint. dont maintain it and a simple problem will destroy a motor. I am with upinsmoke, why make problems when its to easy to install a bulb and test it occasionally. in fact its part of the annual maint. I think it actually self tests when you power up the tach. mine does. but either way its not hard to test it. by testing it you also insure the circuits and wiring are working in the system. quick test is to pull the water trap off the engine tank with the key on and watch for the red light and the audible horn when the level drops below the lower tank mark. if it does not its time to repair the circuit. and by doing that you perform 2 maint steps in one easy task.

 

[edgutgesell]

Re: 150 Yamaha Voltage Regulation

Thanks Upinsmoke and Rodbolt,<br /><br />The answer I was looking for was that the voltage range that I was seeing on the voltmeter on the instrument panel was reflected through the other electronics on the motor and elsewhere. (Thanks Upinsmoke). As I said, I am not an expert on outboard motor electronics. The reason I wanted to know that was that the amount of forward voltage on a LED is important. If the forward voltage is too high, the lifespan of the LED could be significantly shortened, and if it is too low, the light emitted may be insufficient. You made me realize that I will need additional regulation ($4.00) if the LED's are to emit sufficient light and to last up to expectations. <br /><br />Rodbolt, <br />This motor has been regularly maintained by Yamaha <br />trained mechanics and probably wouldn't have lasted as long as it has without that maintenance. Having said that, the engine had maintenance early last year and at that time the oil injection system seemed fine, including the indicators. As I also mentioned, the oil level sensor and the oil control unit were replaced to resolve the oil injection problem. For all I know, the bulb could have burned out when needed because of a faulty output from the defective control unit. I believe that no matter how simple changing an incandescent light bulb is, LED's are vastly superior to incandescent bulbs in service life. I really appreciate your replies.

 

[rodbolt]

Re: 150 Yamaha Voltage Regulation

I would tend to agree if the lights actually stayed on any length of time. however you still have made no mention of hearing the audible alarm when the sensor/alarm system is checked under its periodic maint.<br /> most times the lights dont work due to corrosion. thats why over the years yamaha has continually improved the tach. now its all sealed in the tach and cannot be accesed and uses LCD's. in normal operation the only time you should see the red or yellow lamps is when the key is turned on and it self tests. if they dont come on at the self test its broke and needs fixing whether its filiments, LED or LCD.but if you never ran the engine tank low you will never get a red light. the yellow indicates the remote tank is low and wont automatically transfer oil.<br /> the modules did fail occasionally . usually failed to turn off the transfer. it becomes readily appearent that transfer did not stop if the vent is correctly installed on the tank due to the decrease in performace and "slight " increase in the amount of exhaust smoke .

 

[edgutgesell]

Re: 150 Yamaha Voltage Regulation

Rodbolt,<br /><br />When the original oil injection failure happened, (oil overflowing from main tank on the engine, engine smoking, and engine using oil at a much higher rate), caused me to check the oil level in the tanks visibly while underway. There was no audible alarm. Also no warning indicators at the instruments were on at that time. Found the red warning bulb in tach blown. What blew it, I don't know. I can only assume that the oil control unit was the culprit or the bulb died of old age! The oil control unit (electronic unit with toggle switch) and the oil level sensor in the main tank were replaced with new Yamaha parts by a Yamaha tech. I don't think that the problem I had was due to a lack of necessary periodical maintenance by Yamaha and if so, Yamaha blew it!!! I hope all will be fine now.

 

[rodbolt]

Re: 150 Yamaha Voltage Regulation

do you watch to see if the lights go through the self test each time? and like I say if the engine tank never got low it wont light. if the remote tank still had enough in it it wont light either. either way its not a yam problem. the oil sensor in the engine tank is a 200 hour OR yearly test. the lights self test each time the key is switched on. same as the oil filter in the remote tank. when you say periodic by yamaha you must remember that each dealer is not a yamaha. some do better than others and you cannot run one till it breaks then catch up on maint. cant happen although I see it all the time. with all makes and drive types. I try to get people to test the audible alarm once per month anyway. its relativly important as is the speed reduction mode. the lights may or may not attract attention until its to late.