F225txrd won't start after bone head brother in law worked on it

[Real hillbilly]

So the last Time I had the boat out it ran great. But after shutting down the engine and then trying to restart it sounded like a weak batteries. Noticed while trying to start the batterie terminal would get extremely hot. It would eventually turn over and run great. After talking to a motor head he suggested it could be a fuel injector leaking fuel into the a cylinder causing it to hydro lock. It made sense after checking the oil and smelling fuel mixing with the oil . So I had my spare set of injectors serviced. With that being said I was busy at work and didn't have the time to do the work I let my bonehead brother in law do the work. I walked him thru it which did no good. He disassembled the throttle body instead of removing as a unit to expose the fuel rail. He proceeded to install the fresh injectors and reassemble. When complete the engine would just turn over but never start. After every few attempts it would backfire.i decided to put the old injectors back in and try to start. I got the same it would turn over and back fire. Since then I have changed the coils and spark plugs. The motor has perfect compression at each cylinder and deffently has spark. It also has proper fuel pressure at the fuel rail. The next thing on my list is timing. Any help would be greatly appreciated.

[robert graham]

Hot battery terminal means bad connection there....remove and clean with wire brush and a dab of grease, replace and tighten.....

[99yam40]

I do hope you find some help you here, but trying to figure out what your BIL did to your motor is not going to be easy from a computer way away from the motor.

you will have to start inspecting and testing things to prove they are how they should be

[Real hillbilly]

The batteries are brand new and the connections are bright shining metal. As far as the testing goes I have made sure I have spark fuel and air. I have the proper fuel pressure brand new coils and spark at each plug. I've checked the compression on every cylinder and each is slightly above oem specs. I haven't verified the timing is correct. What stumped me is it ran awesome before I let him work on it.

[TownsendsFJR1300]

You mentioned that batteries "sounded weak".
Have you charged them and had them load tested to make sure their good??
If your connections are clean, bad or low charged batteries would make slow cranking.

Make sure that battery is at 12.8 volts (or more) static. Check cranking voltage as well..

I suspect once running, the engines charging (as you posted it runs good once started), check that as well once it starts.

You can jump start from you car battery to the boat battery (unless the boat battery has a bad internal connection) and the engine should crank over MUCH faster and start.


Once the batteries are ruled as good and it still does not run,
it sounds like you need to literally go over R&R EVERYTHING your BIL touched.
could be a sensor not plugged in, etc. The timing isn't going to change(unless of course he messed with it)..

[ausnoelm]

Back fire seems strange, seeing as someone else has tinkered with it, you will have to start right at the beginning and redo everything he did, then find what he wrecked.

[Real hillbilly]

I was able to get it started yesterday. It shot flames out the exhaust and ran like crap! I checked th compression again and found 1cyl=o 2cyl=0 3cyl= 0 4cyl =90 5Cyl=100 6cyl=120. Not sure what's going on!! Timing appears to be slightly off but not a whole tooth. Stretched timing belt?? Broken valve springs?? Help the big bluefin are biting!!

[boscoe99]

Motor needs to go to a shop that has a Yamaha mechanic on its staff.

[ausnoelm]

Doubt the timing belt has stretched, pretty simple to actually check the timing though.

[robert graham]

Motor needs to go to a shop that has a Yamaha mechanic on its staff.

My 2nd on this great advice!....and just maybe your motor is not already toast!

[ausnoelm]

I was able to get it started yesterday. It shot flames out the exhaust and ran like crap! I checked th compression again and found 1cyl=o 2cyl=0 3cyl= 0 4cyl =90 5Cyl=100 6cyl=120. Not sure what's going on!! Timing appears to be slightly off but not a whole tooth. Stretched timing belt?? Broken valve springs?? Help the big bluefin are biting!!

Seeing as its been run, and has this back firing, and has 0 compression in three cylinders, I don't think your future is looking too bright! you might be lucky and something non terminal has been messed around with, what's the chances he fooled around with the timing? Messed it up big time, then tried to put it back how it was to cover his ass?

[Real hillbilly]

I've checked timing and it's spot on. I just received my YDS and ran it. Only code that came up is the oil pressure sensor. Could a bad ops cause it to only run on a couple cylinders?

[99yam40]

OPS would not cause 0 compression on 3 cylinders