93 200 txrr wont rev over 2000 rpms

[dpfishndoc]

1993 Yamaha 200txrr shakes and cuts out at 2000rpms. Fuel system has had new fuel pumps, three carbs cleaned( three times) and blown out with compressed air ,with new Yamaha kits installed,new fuel-water filter,fuel lines new,good tank vent and siphon valve.Replaced waterpump,thermostates,popit valve.I use 100% senthetic 2 cycle oil and gas is fresh and stabil was added.New spark plugs Etc. The engine oil system appears to fuction and all oil filters looked like new?? Motor starts great and runs up to 2000 . I thought the rusted alarm was bad so I replaced it also . No warning lights indication or alarms have ever gone off . My boats in a slip without a trailer and no Yamaha techs in the area.

 

[rodbolt]

Re: 93 200 txrr wont rev over 2000 rpms

have you actually tested the alarm system? test with key on engine off and ground the harness pink wire at one of the head sensors. test compression and spark. if all tests pass you will need a CD -77 peak reading meter or its equivalent. there are some resistance tests you can run on the stator. do you have a multimeter and do you know how its used? do you have a service manual ?

 

[dpfishndoc]

Re: 93 200 txrr wont rev over 2000 rpms

Compression was 122 psi 1-6 ,good blue spark,plugs normal color. I tried to ground the pink wire on the thermo sensors and no alarm sounded. Have not used a multimeter . I have the seloc manual and its very poor in troubleshooting rpm reduction problems and very little mention of alarms. I was running the motor at 1900 rpms at 8 knots and tilted the motor up to increase revs ( without more throttle) and when it hit 2000 it started shaking and cuting out. I did this to rule out a fuel starvation situation

 

[dpfishndoc]

Re: 93 200 txrr wont rev over 2000 rpms

Rodbolt:Could it be the tilt sensor or other sensors malfunctioning,the alarm won't sound when tested.I'm not familiar with a cd-77 peak meter reading,could a bad stator cause this. The seloc manual has por troubleshooting info. Thanks

 

[rodbolt]

Re: 93 200 txrr wont rev over 2000 rpms

fix your alarm problem first<br /> with key on engine off thest for voltage at the yellow wire at the horn to ground. if you have voltage on the yellow wire bullet connector at the alarm ground the pink wire from the morn to a black wire. at the head temp switches, with the key on and the engine off when you ground the pink wire on the engine harness side to a good block ground the horn should sound. you may be hitting the speed reduction mode and not know it. we need to slove one problem at a time. the speed reduction can work regardless of if the visual or audible indicators are working. do you have the yamaha digital tach and digital speedometer ?

 

[dpfishndoc]

Re: 93 200 txrr wont rev over 2000 rpms

For Rodbolt: Found the problem for the rpm reduction :the port thermostat was not opening normally causing the port cylinder bank to overheat.The thermostat was only 3 months old? Thealarm was tested at the consule and shows 12.3 volts and buzzes when the yellow wire was ground ed,but alarm won't sound when it over heats .The two thermosensor pink and black wires were connected and the buzzer didn't sound.The voltage on the thermosensor wire on the head was 9.3 volts on each sensor. The sensors were tested in warm water and the change in resistance was seen on an ohm meter .The sensor seems to work ,hence the rpm reduction .What could the problem still be and how do I get the(new) overheat alarm to work .Thanks

 

[dpfishndoc]

Re: 93 200 txrr wont rev over 2000 rpms

I have the digital alarm and tach

 

[rodbolt]

Re: 93 200 txrr wont rev over 2000 rpms

you most likly have a problem in the pink wire going from the motor to the alarm. the gray wire, if you have the digital speedo, is for visual indicate. audio is the pink wire. test the system by unplugging the pink lead at the head. take the harness side gray/black to a known good block ground. if it does not work its time to find the break. test all the connectors. the switch in the head just closes the circuit. the gray/blk wire is spliced in the harness. one side goes to a 4 wire plug and connects to a gray at the plug the other side of the gray/blk goes to the CDI. all alarms go from the CDI to the horn Via a pink wire in the 10 pin main harness connector. The grond connection for the horn is made in the CDI. do you have a manual ?<br /> its time to find the bad connection.