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Mr1 intermittent cylinder drop.

Minute 5 to 11 has the good stuff...

So far nobody's ECU has failed open (cannot trigger the injector) so far everyone has failed with the injector receiving 12v...so it's likely to be the injector and not the ECU.

Can you PM me your email? I can send you something out of band. may or may not be the manual..plausible deniability and all.

I literally just finished watching it..
 

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@bronze_10 I have replaced fuel injectors. If your not feeling confident before diving in then I suggest you allow a professional to do it. It is a sizable job and if you get impatient you can break things. However if you want the adventure I found the service manual to be very thorough. I took notes and pictures if you need them. Please let me know.
 
I actually and kinda punting... my mechanic buddy that does all my car repairs if gonna take the lead... he has worked on everything commercial motor vehical to high power racing motorcycles.. he stated he hasnt work specifically on boats like mine but he has done extensive yamaha motor cycle work.... I am going to be the plucky assistant!
 
Please take pictures too! Best of Luck!
 
So in preparing to work on that injector I have been watching youtube videos and I keep running into yamaha injectors having tiny filters in them that need to be changed every so often... anyone ever run into that? Could this injector on my engine have a clogged filter? Would that keep the injector from cycling?
 
Well.... what does the collective wisdom of the forum say? I think I should not have been cheap and just swapped them this spring like I did the starboard engine...

View attachment 95269

The one on the left is the cylinder closes to the bow!
All look normal to me. Late to the game. It seems you may have other issues.
 
@bronze_10 I just looked at some spare ejectors I have. There is definitely a screen in there. I tried to remove it but could not. It seems integrated with the assembly. The manual does not mention being able to remove it.
 
Hard to see but it is on the side wall of the inlet.
20190601_062656.jpg
 
So in preparing to work on that injector I have been watching youtube videos and I keep running into yamaha injectors having tiny filters in them that need to be changed every so often... anyone ever run into that? Could this injector on my engine have a clogged filter? Would that keep the injector from cycling?
A blocked screen would mess up the spray pattern causing the injector to drip rather than atomize the fuel. If your injector is not firing I would think it's a faulty injector. You could swap it to cylinder #2 to prove it.
 
The injector doesn't click with the test in YDS. This points to an issue with either the injector or power getting to it. I know almost zero about this, but based on click pulse not making noise... I don't think it's the screen. If you can swap and somehow keep connected electrically to the boat, you could test on another injector position to ensure the issue moves with the injector. Best of luck, I'm hoping you figure it out soon so you can get back to boating.
 
So question... the air box whee the fuel rail and all are located everything has a thin layer of oil... like the bolt head had small amounts of oil in them and the bottom of the plastic pan has a tiny bit of oil in the corners.... it is normal for this area to have oil like that or is this from the injector sticking on the way back from bimini resulting in fuel in the oil and it over filling?
 
Could very well be the case. I recently looked at mine and no such oil film was present.
 
So, when are you testing with the new Injectors? Best of luck!!!!
 
They come in next week...now that I have it on the bench I am gonna pi
Ull the injectors and ohm test them.

Any recommendation on a degreaser sort to use on this stuff that won't hurt anything?
 
Well... I did take out 9 quarts of oil out of that motor when I got home!
So nearly twice the amount that's supposed to be in there?
 
I would not strip them off the oil beyond a paper towel wipe. If anything it offers extra protection against corrosion.
 
So question... the air box whee the fuel rail and all are located everything has a thin layer of oil... like the bolt head had small amounts of oil in them and the bottom of the plastic pan has a tiny bit of oil in the corners.... it is normal for this area to have oil like that or is this from the injector sticking on the way back from bimini resulting in fuel in the oil and it over filling?
I noticed this same thing a few months ago. I thought it might be normal. Also not sure if I need to change my air filters. They look a little dirty.
 

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