'91 Yamaha Oil Pump/Reserve

[SctSimpson]

I've got a '91 175HP Yamaha O/B with a Reserve Oil Tank on the boat. Right now the emergency switch on the engine will pump oil from the reserve tank (so the pump, and all oils lines are good), however the CDI Unit will no longer active the pump when the oil in the integral tank gets low, it will however sound the buzzer alarm when it gets too low.<br /><br />I've check all of the wiring for continuity (at least that I can think of), the oil level sensor in the integral tank registers on the gauges correctly (Green and Yellow as you move the sensor in and out of the tank), and I just replaced the sensor in the integral tank with no success.<br /><br />All of this started occuring just after I replaced the gauges in the boat, but I'm at a loss to figure out how that would effect the oil transfer (in fact I've put the old gauges back in and that did not resolve the problem).<br /><br />Any suggestions on why the engine (CDI) would stop sending the transfer pump a signal?<br /><br />(Sorry for the long post, wanted to be sure everyone had all of the info I know).<br /><br />Thanks,<br />Scott

 

[rodbolt]

Re: '91 Yamaha Oil Pump/Reserve

usually its the switch in the engine tank. CDI failures are rather rare but do occur.<br /> with the key on and the engine off dissconect the engine oil tank connector. jump the brown wire (may be blue/green) to the black wire. pump should turn on in the remote tank. to stop the transfer jump the white wire(may be blue/white) to the black. if the trnsfer wont start jump the brown or blue/green to a known good ground. if it starts on a known good ground and not with the black wire find the break in the ground circuit on the black wire. once turned on the only way to turn it off is ground the white or blue/white or turn the key off. someplace on here, Seahorse has the site, is a good test procedure for the precision blend system. its very simple but requires reading how it works and why.

 

[SctSimpson]

Re: '91 Yamaha Oil Pump/Reserve

Thanks rodbolt - heading to the garage now to give it a try now.

 

[SctSimpson]

Re: '91 Yamaha Oil Pump/Reserve

Had the blue/green, blue/white, black (and a blue/red) color coding - it would not cut the transfer pump on either way (tried to jump blue/green to black, and blue/green straight to the neg. terminal on the battery).<br /><br />Thanks again, I'll search around for the test procedures - would love to understand a bit more on how it works.

 

[SctSimpson]

Re: '91 Yamaha Oil Pump/Reserve

For informational purposes - I finally figured out the problem (thanks rodbolt for pointing the direction):<br /><br />The Telflex Trim Sensor Gauge does not work with '90 and up (I believe this was the range) Yamaha engines. There is some circuirty in the Yamaha trim senor gauge that relays the "engine up" position back to the CDI, thus defeating the switch to turn on the transfer pump. Connecting the Telflex gauge somehow overrides this - as disconnecting the Telflex gauge (running no trim sensor) allows the transfer pump to cut on correctly.<br /><br />Anyone with any information regarding how the trim sensor and gauge work on a '91 175 O/B - I'd appreciate it. There's three lines coming from the trim sensor (black, pink, and orange) Teleflex states to connect the pink to the gauge which reads the resistance from the sensor, and DO NOT connect the orange (got no clue what it's for right now)...<br /><br />Thanks,<br />Scott

 

[cpj]

Re: '91 Yamaha Oil Pump/Reserve

Scott, even though you fixed it here is something that is an interesting read on how the yammy oil system works.http://www.bassandwalleyeboats.com/output.cfm?id=942859

 

[rodbolt]

Re: '91 Yamaha Oil Pump/Reserve

toss the teleflex junk and rig your machine correctly. faria,teleflex its all junk in the box. at least its cheap though

 

[SctSimpson]

Re: '91 Yamaha Oil Pump/Reserve

Thank cpj, found that one yesterday which helped point to the trim system.<br /><br />Any suggestions for gauges (any sites with Yamaha replacement, analog gauges)? One of the factory digital multigauges is cracked and the wife doesn't like the "looks" of the "old" gauges. Trying to update the looks of the boat to prevent the "I want a new one" syndrom <br /><br />Thanks again for the help.

 

[rodbolt]

Re: '91 Yamaha Oil Pump/Reserve

you will need the yamaha analog gauge for the 3 wire sender. <br /> none of the aftermarket stuff seems to work correctly with the yamaha. the new multifunction tach can be back fitted with the correct harness adapter and has an hour meter as well as the trim meter built in.