Please help, Problem with 115 Yamaha & dig tacho.

Longboarda

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Jan 28, 2005
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I have been having some problems with my outboard 19 :mad: 98 model 2 stroke 115hp. I noticed that my digital tacho was not working correctly as it was only displaying a single digit 1 or a 3. Soon after that the outboard started to miss fire almost like it was running on 3 cylinders, as the day went on the miss got worse and it got harder to start, the amps were starting to drop below 11.4 (normal operation 14.6) <br />I have had the boat looked at for the last 3 weeks and the mechanic thought he had fixed the miss by replacing the regulator/rectifier (tacho still not working $720 for a new one????) <br />I took the boat out yesterday and after a few minutes it start the miss again. And then stalled 30 minutes later it started and ran like a dog. If anyone has had the same or simalar problem please give me some feedback as the mechanic has no idea what it could be !!!!! <br />So far it has cost me $600 for nothing, not happy!!!!
 

rodbolt

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Re: Please help, Problem with 115 Yamaha & dig tacho.

hello<br /> I would find another tech. there is nothing on a 115 2 stroke that connects the ign and charging system other than the stator. and the high and low speed charge coils are not part of the battery lighting coils.judging from your problem you may have a faulty ground someplace. so now a thourgh diagnostics is nessasary to eliminate things. you will need a service manual a CD-77 peak reading meter (or equivalent peak reading meter) and a compression tester as well as a VOM.start with a compression and spark test. compression should be within 10 psi and all plugs should be able to jump a 7/16ths gap.get a copy of the tune-up spec guide as well (part#Lit-18559-94-05). test stator and trigger outputs, preferably while the engine is running and missing. test CDI output. here again preferably while the engine is running and missing. all the outputs from the ign system and battery lighting coils can be tested with a CD-77. but the only thing related to a battery charging failure and an ign miss will be a stator. other than the stator and flywheel the two systems are not related. if your tech cannot produce a copy of the service manual or at least the tune up specs and a PEAK reading meter dont even bother going back.
 

Longboarda

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Re: Please help, Problem with 115 Yamaha & dig tacho.

Thanks for your input to my problem, it has been very helpful. It is really frustrating to pay someone to just remove and replace parts that were ok in the first place, so much for there experience. Why can't techs just tell you when they can't fix it!
 

rodbolt

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Re: Please help, Problem with 115 Yamaha & dig tacho.

hello<br /> I did not say your old rectifier assy was good and needlesly replaced. what I said was that to have a charging system failure that would affect ign operation would have to involve some type of stator failure on the 115 2 stroke yamaha.<br /> that is why I said a full diagnosis is in order. but you also have to have the correct equipment to test it. the CD-77 meter is almost 250 dollars here<br />after the repair did the tach work ?
 

Longboarda

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Re: Please help, Problem with 115 Yamaha & dig tacho.

No the tacho didn't work after the rectifier was replaced, so my tech disconnected it from the motor but left the power supply connected. <br />He did work at a Yamaha dealer so I hope he has been trained to work on Yamaha's. He thought that he had fixed the problem so now it has got him stuffed, as he had already checked all of the earths and coils act, I think he might want to change the CDI unit next AU$700 and this part once used can not be returned. So it could be time to get a new tech as you said.
 

rodbolt

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Re: Please help, Problem with 115 Yamaha & dig tacho.

that is what I would try. the tach signal comes from the stator and is picked off at the rectifier. a rectifier failure can affect the tach signal. but when you turn the key to on it should still selftest and read zero. I have seen CDI failures. its damn rare and I would demand to see the test results obtained with a peak reading multimeter such as the CD-77 both loaded and unloaded before I bought a CDI. now that he hs fixed it tell me all the symptoms again. do you get a zero rpm reading with key on engine off and does the tach self test when the key is on ?
 

Longboarda

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Re: Please help, Problem with 115 Yamaha & dig tacho.

Not fixed yet, the tach is showing a "E" flashing which quickly changes to a "1" and there is a pointer showing on the green box at the bottom of the tach. (The tach is not connected to the motor)<br />only power.<br /><br />temp
 

rodbolt

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Re: Please help, Problem with 115 Yamaha & dig tacho.

hello<br /> if you have 12 volts to the tack and it self tests by lighting up all the oil arrows, the trim bars and flashes the tach then goes to 1 you most likely have either very low voltage to it. check for 12v between the black and yellow tach leads or a bad tach. by flashing its try to self test.
 

Longboarda

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Re: Please help, Problem with 115 Yamaha & dig tacho.

Can you test the digital tach ?<br />If the digital tach is faulty I will buy a new anolog tach.<br />Are you referring to the starter motor when you say "stator" ?
 

Longboarda

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Re: Please help, Problem with 115 Yamaha & dig tacho.

Thanks for your feedback...<br />My problem has been fixed(after 7 weeks) it appeared to be a faulty stator ( as you suggested). It was the last thing the mechanic looked at.<br />Once again thank you.<br /><br />Jason.
 

Longboarda

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Re: Please help, Problem with 115 Yamaha & dig tacho.

Thanks for your feedback...<br />My problem has been fixed(after 7 weeks) it appeared to be a faulty stator ( as you suggested). It was the last thing the mechanic looked at.<br />Once again thank you.<br /><br />Jason.
 

rodbolt

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Re: Please help, Problem with 115 Yamaha & dig tacho.

glad yta got it fixed. hope all is well. but its an easy find. if I were you I would start hunting for a tech that relies on troubleshooting skills and less on blind luck, we have a saying here that even a blind squirrel finds an occasional acorn. no mention of how many holes he dug to find it :)
 

Longboarda

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Re: Please help, Problem with 115 Yamaha & dig tacho.

rodbolt<br /><br />Thanks for all of your posts on this problem and yes you are right on with your last comment....<br />I will not even take my wheel barrow back to that #%*&* <br />once again thankyou.
 
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