XR1800 4-Stroke MR1 Swap

[Robb235]

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!

Just got back in town last night, plan to troubleshoot shoot this tonight if I have time.

 

[Robb235]

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.

 

[Robb235]

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.

 

[Robb235]

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?

 

[Beachbummer]

If I was me, I'd suggest Spend no more cash until after you try it. Depending on your experience while running, you can then make the right adjustments to impeller pitch. (If applicable)

You will be breaking new ground here so making adjustments based on your performance is probably the safest bet.

 

[UnorthodoxCreations]

I agree, try what you have before buying more. I'm guessing the new setup weighs a little more and negates the horsepower gain anyways.

 

[Robb235]

Not really sure how much of a true benchmark my 20 year old stock impellers will give me.

 

[Robb235]

Can you cut the throttle cables and put something like these on? https://www.napaonline.com/en/p/NOE...s8x_r2Gcfgx1pnWhB4aAoo7EALw_wcB&gclsrc=aw.ds& You can put a little solder on the ends of the cable to make them stronger and keep them from fraying.

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.



Corsa Technic has been an awesome resource for finding OEM connectors for this project: Connector Kits, Terminals, Wiring, Tools | Corsa Technic

 

[Robb235]

Goodness, going into my third season working on this conversion. Snow in the winter time just isn't conducive to working on a boat that stays outside. Oh well, I said in the original post that progress would be sporadic, and that has certainly held true.

Anyways, I've extended the wiring for both engines' YDS plug-in to underneath the steering wheel. This is much more convenient to be able to sit in the captain's chair and plug into YDS, as opposed to popping the engine hatch and having the laptop sit on the rear seat (YDS cable isn't long enough to reach from engine compartment to the captain's chair).

I have an electrical gremlin I'm trying to figure out on the starboard side motor. I think it may be related to my bypassing of the security box. The port engine behaves as it should: when I key ON, the fuel pump primes, and if I key OFF in the middle of priming, the fuel pump immediately stops priming. Which is how it should behave. But the starboard engine, when I key ON fuel pump primes, but will continue to finish priming, even if I immediately key OFF. It shouldn't do that. If I bump the starboard starter, then key OFF and go back to key ON, it does not prime again. I have to wait about 30 seconds or so (I can then hear the main relay switch off) until I can key ON again, and prime the fuel pump once more. Something is keeping the main relay and/or the ECU awake for about 30 seconds after I key OFF, which shouldn't be happening. Whenever I key OFF, the main relay and ECU should be immediately killed, like is happening with the port motor. The starboard start will engine and spin the motor whenever I key START, but motor does not fire up.

I swapped the wiring temporarily so that the port key operated the starboard motor. Starboard motor behaved exactly the same, so as far as I can tell, the issue is not with the ignition switch, or any of the wiring under the dash. Seems like it's probably wiring or ECU in the engine compartment. Examining the wiring of the security system bypass, everything looks correct. But I may redo all the connections on the bypass anyways, just to make sure.

Once I get this electrical issue figured out, I will be ready for testing in the water.

 

[Robb235]

Ok, figured it out. The issue was a dead fuel pump for the starboard motor. It was a new pump, so I'm a bit surprised it died so quickly. It sounded like it was priming like it should, so I never suspected it at first. I had YDS hooked up and when I went to do the individual test on each fuel injector, I noticed the clicks from the starboard motor sounded different from the clicks emitted by the port motor. Disconnected the fuel line, placed it in an empty gas can, and sure enough, when I put the key to ON, it sounded fine, but no fuel was pumped into the gas can. I replaced the fuel pump with the spare that I had used for bench testing, and then it fired up no problem. I also modified my security system bypass a little bit more and now the starboard motor behaves exactly like the port motor does.

Video of both motors starting up. Excuse the dirty engine bay!
XR1800 MR-1 Swap: In-boat Startup

 

[84rzv500r]

Ok, figured it out. The issue was a dead fuel pump for the starboard motor. It was a new pump, so I'm a bit surprised it died so quickly. It sounded like it was priming like it should, so I never suspected it at first. I had YDS hooked up and when I went to do the individual test on each fuel injector, I noticed the clicks from the starboard motor sounded different from the clicks emitted by the port motor. Disconnected the fuel line, placed it in an empty gas can, and sure enough, when I put the key to ON, it sounded fine, but no fuel was pumped into the gas can. I replaced the fuel pump with the spare that I had used for bench testing, and then it fired up no problem. I also modified my security system bypass a little bit more and now the starboard motor behaves exactly like the port motor does.

Video of both motors starting up. Excuse the dirty engine bay!
XR1800 MR-1 Swap: In-boat Startup

Very cool I'm right behind you... I'm integrating the boat harness with the MR-1 harness.. getting really close hope to be firing up this weekend

 

[Robb235]

Very cool I'm right behind you... I'm integrating the boat harness with the MR-1 harness.. getting really close hope to be firing up this weekend

Nice! Let me know if you have any issues with the security box. I had to perfect the bypass a couple times until I got it exactly right, and behaving the way it should.
If the weather holds, I’ll hopefully be water testing this weekend.

 

[84rzv500r]

LOL thats what Im working on now.. I have main and starter relay and power to things in engine harness but the ECU is not waking up... So i suspect i am missing the signal from the 18 pin ( ground or continuity) to wake up the ECU... I need to find the beeper in the ski for the audibles...

so if you have a revised pinout list that would be cool..

I was able to get one set of connectors from the donor ski... I have a boneyard guy in Tampa that will get me the others as soon as I send him the list and pics... I haven't looked for the 18 pin yet to replace the remote control box... just been using some wire wrap wire to break out the pins...

I also built up a old laptop and put YDS on it... and I've been holding off on BUDS cause I do wanna eliminate the DESS on my Seadoo and the key to do that is annual and expensive (Yet another Project(

 

[Robb235]

LOL thats what Im working on now.. I have main and starter relay and power to things in engine harness but the ECU is not waking up... So i suspect i am missing the signal from the 18 pin ( ground or continuity) to wake up the ECU... I need to find the beeper in the ski for the audibles...

so if you have a revised pinout list that would be cool..

I was able to get one set of connectors from the donor ski... I have a boneyard guy in Tampa that will get me the others as soon as I send him the list and pics... I haven't looked for the 18 pin yet to replace the remote control box... just been using some wire wrap wire to break out the pins...

I also built up a old laptop and put YDS on it... and I've been holding off on BUDS cause I do wanna eliminate the DESS on my Seadoo and the key to do that is annual and expensive (Yet another Project(

Are you currently using the security boxes or did you remove them? Did you run switched power from when the key is is ON back from under the dash back to the engine bay? Each key should have a purple wire that is hot when key is ON.

What is BUDS?

 

[84rzv500r]

not using security boxes... Ignore BUDS... YDS is to Yamaha as BUDS is to Bombardier... i run multiple projects in parallel so when I get bored or stuck on one I can go work on the other for a while

 

[84rzv500r]

also not using the MFD...

 

[Robb235]

not using security boxes... Ignore BUDS... YDS is to Yamaha as BUDS is to Bombardier... i run multiple projects in parallel so when I get bored or stuck on one I can go work on the other for a while

What have you modified or spliced on the engine wiring harness so far? You shouldn't have to do anything, except to some modifications to the plug that goes into the 18-pin security box.

I'll mark up a PDF of the wiring diagram to show what I did to by pass the security box. I'll post here shortly.

 

[Robb235]

Ok, hopefully this diagram explains how to bypass the jetski security system. Markups in Red explain what the function of the wire is. Markups in Green are instructions to bypass the security box.

 

[84rzv500r]

Ok, hopefully this diagram explains how to bypass the jetski security system. Markups in Red explain what the function of the wire is. Markups in Green are instructions to bypass the security box.

Thank You I was close... it looks like I was missing the blue wire to ground... does the ECU beep without this wire grounded ?

 

[Robb235]

Thank You I was close... it looks like I was missing the blue wire to ground... does the ECU beep without this wire grounded ?

I don’t remember. I think it just wouldn’t start. I wish I understood what the purpose is for that blue wire. It’s been bugging me.