MR-1 Engine maxing out at 8500 RPM

[Hike]

@tdonoughue, good suggestion. I removed and inspected the air filters. I'm running Riva Hi-Flo filters, similar to K&N. They are usually not effected by oil splatter and the bottoms of them were pretty clean. I also removed and re-insalled the wiring harness to the spark plug boots and reseated them. The spark plugs were brand new and since I didn't have any spares, I didn't try changing those. The Yamaha tech said he would give it a water test soon. They said an AR 210 came in today with the same problem of one engine revving lower than the other. I hope it's something that doesn't need a part ordered. I waited three months for 4 bolts for the pump housing, finally ordered them off eBay and shipped to the dealer! C'mon Yamaha.. you're taking away my boating time!

 

[tdonoughue]

Sounds like you did all the right checks. Hopefully they don't even need a part and you can get back very soon.

Around here, it just rains... Might as well have my boat at the dealer. <sigh>

 

[Hike]

If both engines can hit 10,000+ while on the hose out of the water… could it still be a fouled spark plug?

If so..
If the dealer can’t get to it this week, I may pick it up and try swapping the spark plugs.

 

[Hike]

Yamaha Dealer says:
**TECH NOTES**
-FOUND PORT SHIFTER/THROTTLE ASSEMBLY HAS EXCESSIVE PLAY IN PIVOT
-STARBOARD SHIFT CABLE GETTING TIGHT (FAILING) - DISCONNECTED @ SHIFTER AND PUMP TO VERIFY CABLE ISSUE.

but they say all parts are discontinued so they won't repair . however I did find all parts except lever on eBay.

Does this seem right for my throttle drop issue? I tried the throttle drop mod which didn't make any change.

F2A-U149C-00-00 2.00 CABLE,REVERSE $115.69 $0.00 $231.38


EU0-61461-30-00 2.00 SHAFT, JOINT BALL $51.69 $0.00 $103.38


EU0-67267-00-00 1.00 CONNECTOR CABLE $41.99 $0.00 $41.99


F1C-U134A-21-00 1.00 REMOCON LEVER ASSY $867.99 $0.00 $867.99

 

[tdonoughue]

I would just start with the shift cable and see how it goes. Your excess play may be worse because it is pushing so hard against the cable. You may also find replacing the cable that you can figure out a just-as-good fix for the pivot point (like a bolt or something). If not and it remains a problem, then you can spring for the other parts (and will have a better idea which ones, having had the shifter off to replace the cable).

 

[Hike]

@tdonoughue Thanks for the input. Should I go ahead and replace both the cable reverse for the buckets as well as the throttle cable?

 

[tdonoughue]

I would not if they are not causing issues. But if they are starting to gum up, too, then yes.

 

[Hike]

Just spent $2k in dealer suggested parts and service and still no change

They Installed new throttle levers, throttle cables, reverse cables and associated parts and claimed to have adjusted it to spec.

Port engine still maxes out at 8500 rpm.
Wondering if Impros didn’t pitch these new solas impellers correctly?

 

[mrcleanr6]

Did you chk the injectors like i mentioned? It takes 10 min to do and cost nothing. After that a coil chk. Disconnect one coil at a time at idle. Each one you disconnect should make a difference in engine idle. If you fine one that doesnt then you found your bad coil, injector or cylinder.

 

[Hike]

Did you chk the injectors like i mentioned? It takes 10 min to do and cost nothing. After that a coil chk. Disconnect one coil at a time at idle. Each one you disconnect should make a difference in engine idle. If you fine one that doesnt then you found your bad coil, injector or cylinder.

I didn’t try that yet.. I’m fairly handy but haven’t tried something like that before. Do you happen to have a service manual for our boats so I can see what I need to do a little more clearly? Any pics? Thanks

 

[Seadeals]

I agree with the injector and coil checks. At idle on the hose should be enough to hear a problem. Compression check would also let you know if there is a cylinder issue followed by ECU swap if that all looks good.

 

[mrcleanr6]

i dont have one. someone on the site has to have one though. the procedure wont be in the manual. pull the airbox lid off so you can see in throttle body. remove the rubber velocity stacks then remove the allen bolts, 8 i think, holding the throttle bodies to the intake manifold. leave fuel connected. rotate the throttle body assembly 180 deg so the bottom side you just unbolted is now facing up. crank the engine and you can watch each injector fire off in to the air. it will tell you which one is not firing or 1/2 clogged in some way. if all are good then just bolt it back up.

 

[mrcleanr6]

for the coil check, run the engine on the hose. one at a time pull the plug going to each coil. you when you pull the plug the engine should idle rough because its now running on 3 cyl. put the plug back on the coil and move to the next one. if you find one that doesnt make any difference in the running of the motor when you disconnect it then you have found you bad cyl. it could be bad from a bad coil, injector not firing, low compression, etc.

 

[Hike]

I agree with the injector and coil checks. At idle on the hose should be enough to hear a problem. Compression check would also let you know if there is a cylinder issue followed by ECU swap if that all looks good.

Compression check from the dealer showed 180 for each cylinder. The coil check sounds easy enough, unplug each spark plug, correct? What are the steps for checking the injectors?

 

[mrcleanr6]

unplug one, listen, reconnect, repeat on next cyl.

for the injectors just do what i said in the post. you can see them fire off and spray into the air. if one isnt firing at all or the spray looks different than the others then you found the problem

 

[Hike]

unplug one, listen, reconnect, repeat on next cyl.

for the injectors just do what i said in the post. you can see them fire off and spray into the air. if one isnt firing at all or the spray looks different than the others then you found the problem

Not sure how to pull the intake off, unbolt the throttle body assy… anyone have any pics of which bolts to take out for this?

 

[mrcleanr6]

not the intake, just the black cover for the airbox. then pull the velocity stacks off and the 8 allen bolts holding the throttle bodies on. once you open it up and look at you will see what needs to be done. i think there may be a wire that needs to come off to rotate the TB around then once its rotated you connect it back up.

 

[Hike]

not the intake, just the black cover for the airbox. then pull the velocity stacks off and the 8 allen bolts holding the throttle bodies on. once you open it up and look at you will see what needs to be done. i think there may be a wire that needs to come off to rotate the TB around then once its rotated you connect it back up.

Ahh, this is starting to make sense! Thanks for walking me thru it

 

[Hike]

As I was detaching the spark plug coils, I found one that didn’t make a difference in the engine idle. Replaced spark plug, still lower rpm.

i swapped the bad coil with another cylinder. Confirmed it’s a bad coil (the engine doesn’t change idle as it follows the bad coil)

So does anyone have a part for a new coil? Or is their a way to clean out my existing one?

Thanks!

 

[feziwig]

This should be it.
6d3-82310-01-00