Yamaha 200 v6 2 stroke only runs on emergency mode

[rodbolt]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

hello<br /> that yellow wire is key on 12volts. it has several splices inside the main harness. the black wire that is cut off is a ground and needs to go somewhere. it could actually be your problem. if all the sensor outputs are good then untape the main harness for inspection. there are many splices in it and blacktape has a tendancy to trap moisture and salt.<br /> good luck and keep posting

 

[tonydwood]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

rodbolt, thanks again i have undone the harness. There was actually only one splice in it. A pink wire to the two top thermostats and the connection was good. All other leads are straight through to outside connectors that i have cleaned or from the power pack . I will connect the black wire to earth. any suggestions for the floating yellow that goes over towards the solenoids on the port side and ends in mid air? If the cpu has a 12 volt supply, can this be checked with a meter? thanks tony

 

[rodbolt]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

not without seeing it. the oil controler had a yellow wire to it as well. if its missing though oil wont transfer. does your CPU have a yellow wire running from the engine harnees 10 pin connector to the CPU? what your doing when bypassing the the CPU is running a fixed timing. the timing is about 7*BTDC when fixed. all the CPU does is allow for variable timing and spark knock detecting it also controls cold start timing useing a thermister. the two sensors one on each head with pink and black wires are actually switches. they detect overheat. does your tech have the yamaha diagnostic light? if not you need to hook it up and read any codes. I still think the ECU is not getting 12 volts or its lost the TPS signal. <br /> good luck and keep posting

 

[tonydwood]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

Rodbolt and all, found it! fixed it! The earth wire from the cpu attached to the block with a bundle of others. The bolt was short and had stripped the top 5 mm of thread, giving a loose connection. I replaced this bolt with a longer one that then gave a tight earth and bingo! it all works again.<br /><br />I think what happened is that the tech that replaced the piston overtightened the earth and stripped it. This then led to the poor connection and the initial breakdown. The problem was not picked up by the yamaha dealer and i found it by following each connection as you suggested and agonised over each one.<br /><br />thanks for your help guys, let me know if you ever come to brisbane regards tony

 

[rodbolt]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

tonywood<br /> I may take ya up on that <br /> once this property sells I am going to fly space A on some military flights. the land down under is high on my list to see. all the kids are gone the ex wife aint botherin me much and its time to see the world but christmas I hope to spend in Venezuela tarpon fishing in Rio Chico and soaking up rays on margarita island <br /> good luck and I told ya it was a loss of signal <br /> PS any military airbases near you ?

 

[tonydwood]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

Rodbolt, "retirement" sounds good. my date is set for my 92 nd birthday, that's when all the kids will be gone. We have a large military air base within 25 miles. I have been flying for the past 35 years, but gave my license up recently to do more boating.<br />thanks again tony

 

[tonydwood]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

Hi Guys, The gremlins are back! Put it in the water for the first time yesterday and while it started on dry land before we left it would not start in the water. then it did start and run for about 1 minute and resused to spark again. connected the A to B bypassing the cpu and it ran like a dream all day. So - we have an intermittent fault - connection. all of the gauges seem to be working ok rpm, trim, temperature. I will check the earth again and resolder the joints. any other suggestions?<br />thanks tony

 

[tonydwood]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

PS just to confuse you i just connected it back to normal mode without touching anything else and guess what? started and runs ok (out of water). Will try again today back in the water.

 

[Ray Neudecker]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

You may want to carefully clean and spread the contacts in that harness that connects back to the computer.

 

[rodbolt]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

hello <br /> if it sparks with the cpu bypassed that tells me the timer, stator and cdi are working. the timing should be fixed at about 7*BTDC. i think your wiring harness is bad. you say the CPU was replaced with a known good one. if so that leaves the harness between the starter solinoid and the cpu. somewhere your either loosing a power feed or a ground to the CPU. have your tech install the dianostic lamp and see if it shows any codes. I think even on that old CPU there is a code for CPU failure. remember that a ground loss or power feed loss will be seen as a cpu failure as well.<br />good luck and keep posting<br />ps remember with the CPU bypassed the battery is no longer required for ign.

 

[Ray Neudecker]

Re: Yamaha 200 v6 2 stroke only runs on emergency mode

I have seen this problem caused by the connections between the main wiring harness and the harness going to the switch or control box also. cleaning and spreading the contacts for better connection was the cure.