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Guest, we are pleased to announce that Hydrophase Ridesteady is offering an extra $50 off for JETBOATERS.NET members on any Ridesteady for Yamaha Speed Control system purchased through February 14th, 2022. Ridesteady is a speed control system (“cruise control”) that uses GPS satellites or engine RPM to keep your boat at the set speed you choose. On twin engine boats, it will also automatically synchronize your engines.
Do you get voltage to the little wires in the starting relay when you turn the key? The relays have gone bad before. (checking that would confirm your suspicion that the ECU is not sending power for another reason, or if the relay is bad) Good Luck!
Turned out I didn’t have the waverunner security system 100% bypassed. Now I do. I can completely get rid of the security box too. Both fuel pump primes with IGNITION ON, and both motors start and run.
Next I need to figure out my throttle cable situation.
So a little bit of bad news. After playing around with the three warning lights on the tachometer, and wiring them back to the ECU, I don’t think there is any way to get the ECU to trigger those warning lights. Even though pins 23, 24, and 25 are unused on the jetski ECU, I was hoping they’d at least still be active so that I could connect to them for the low-oil, overheat, and check engine lights on the tach.
The XR has its own stock warning lights on the dash (independent of the warning lights on the tach): two overheat lights (starboard and port), low fuel, and one low oil light intended for monitoring the 2-stroke oil tank (which is no longer there). I spliced the XR’s stock overheat lights directly into the thermoswitches of the MR1s. Tach warning lights are wired back to the outputs on the ECU. I simulated an overheat condition by disconnecting a connector from the thermoswitch and jumping the connector. As expected, the stock XR overheat light triggered immediately, but the overheat light on the tach never lit up.
So as it stands now, I don’t see any way that I can monitor for a check engine light while I’m on the water. For low oil, I can probably repurpose the XR’s warning light for low 2-stroke oil. I would have to wire it up in such a way that either motor could set off the light. I wouldn’t know which motor had the low oil condition, but at least it will alert me to knowing there’s a problem.
Any suggestions for new impellers? Solas has the 13/19 Concord recommended for the XR1800 on their website. Do I go with something slightly steeper to account for the alleged 5hp increase in each motor?
So over the weekend I figured out my throttle cable situation. At least temporarily. I went with something very similar to what @UnorthodoxCreations suggested, and bought the Dorman 03336 throttle stops from AutoZone. I used the smallest 1/8" stops in the assortment. I cut the end of my throttle cables off with my Dremel, and then had to drill out slightly larger the holes in the throttle stops in order for the cable to thread through. Cut off the excess cable poking through the other end of the throttle stop, and hooked it up to the MR1 throttlebodies. Not sure that this will be a permanent solution, but now at least I could start the motor and blip the throttle. Nice to hear that sport bike sound, makes me miss my Yamaha R6 that I rode through college.
So the stock throttle levers now only use about half of the throw when hooked to the MR1 motors. I had a couple minutes of free time, so I pulled out the shifter/throttle lever assembly and I think I can move the throttle cables to different hole that is closer to the center of the rotating lever so that the throttle cable moves less. I didn't get to study it very closely, but it might be possible to move the throttle cable to a different hole that results in utilizing more (maybe all?) of the throttle throw.
Also, I ordered some additional 3-way electrical connectors so that I can extend the data ports from each engine wiring harness in the engine bay, to underneath the steering wheel. It will be nice to be able to sit in the captain's chair and be able to use the Yamaha Diagnostic System (YDS) on my laptop, instead of having to pop the engine hatch and remove the tray in order to plug YDS in. I'm going to plug into the existing connector on the wiring harness, run the wires to underneath the steering wheel, attach the mating connector, and zip-tie out of the way under the steering wheel and cap it with a blanked off connector. Will be much like the OBD2 ports in most cars under the steering wheel.