01 yamaha 150hp low rpms

[robaloroger]

I just picked up a 2001 yamaha 2 stroke txrz.. The previous owner said they were riding and it was fine then they turned the motor on to head in and they could only run just under 3000 rpms. The oil level was good and no low oil on tach..The motor still had a good flow of water from the pee hole.. I had the same problem on a 99 txrx and it was the external oil tank pump..Compression 110-120 on all 6..I dont know if there are any oil sensors or relays on the motor that might need to be replaced? I know these motors are great.. The motor does everything possible to keep from blowing up..
Thanks

 

[rodbolt]

Re: 01 yamaha 150hp low rpms

dunno what was wrong with your 99 TXRX but it was NOT the remote tank as there are simply no alarms associated with the remote other than a low tank level visual indicate.
no oil sensors or relays on either motor above.
my guess would be lack of fuel in the intake

 

[robaloroger]

Re: 01 yamaha 150hp low rpms

dunno what was wrong with your 99 TXRX but it was NOT the remote tank as there are simply no alarms associated with the remote other than a low tank level visual indicate.
no oil sensors or relays on either motor above.
my guess would be lack of fuel in the intake

on my 99 I did have the low oil on the gauge but the remote tank pump was bad.You actually told me how to diagnose the problem(about 1 1/2 years ago)Thanks again for that..
For the 01 txrz the fuel filter is clean and was ran on a portable tank with clean gas and same problem.. I do not have remote tank or gauges yet. I am going to test the fuel pump and I will probably try to rebuild the carbs and see if it helps. What else would cause lack of fuel in intake?
Thanks

One more thing.. A supposed tech looked at the motor then told the previous owners to buy a new motor.. TO ME a motor with good compression and runs does not seem like a motor beyond repair.. He might of just been trying to buy the motor for peanuts.. Which they ended up selling it for anyways..

 

[rodbolt]

Re: 01 yamaha 150hp low rpms

post a full model number so we know which system is being disscused.
a bad transfer pump will lead to low engine oil tank level which in turn will lead to RPM reduction and an alarm. but not simply low RPM.
check the alarm system and see if it actually works.

 

[robaloroger]

Re: 01 yamaha 150hp low rpms

the model is 150txrz. I dont have any gauges,alarm, or ignition for the motor.. I have it on a stand.. It might be hard to diagnose until I get it rigged.. This week I will back my boat to the garage and pull off the rigging from my txrx and rig the txrz so I can diagnose..I should have enough slack on the wires..I am assuming it was not the transfer pump because the previos owner got another yamaha and probably would have had the same problem because they kept the oil tank.. But who knows..