yamaha 2008 115hp starting problem

[yachtbeaver]

One of our 115hp fuel injected yamaha won't start this morning (one of two installed). First it started and died after 2-3 seconds. Choked to life once more. 3rd time burped. (anyway that what my wife says happened)

Instrument gauge and alarms OK
Turns over strong
Getting fuel all the way to the filter bowl.
Checked ignition by squirting a bit, then a lot of easy start - nothing. Quite sure its an ignition related problem.

Swapped harness plugs at the key switch and another smaller harness.
Checked fuses.
Checked engine side connector plugs, wires etc.

Boat gone fishing anyway but when it comes back plan to swap harnesses with other working engine (if long enough to reach).

Problem is we are in the Exumas with no outside professional help

We tow the boat behind a yacht. It was rough today and maybe the harness run is damaged somewhere. We recently put in new harnesses and better runs for a different problem. Any ideas on how to further trouble shoot (and avoid swapping harnesses)? have a spare engine harness.

I have now swapped the harness and the problem remains so its something wrong under the engine cowl. Also made a few calls and I'm told its either the "trigger or charging coil". So not much can be done until we are back to a service center.

 

[99yam40]

Re: yamaha 2008 115hp starting problem

Fuel injected motors do not have a choke.
Could be a fuel problem such as a pump or filters. You need to test the fuel pressures.

I would recommend to pick up the Yamaha Service/repair manual for those motors and the proper testing equipment needed to keep with the boat while out and about like that. At least you would be able to tell what parts are needed and maybe find them somewhere close by. If you know how to troubleshoot the motors you are way ahead of the game.

 

[yachtbeaver]

Re: yamaha 2008 115hp starting problem

Thanks for the help.

Yamaha service came in today. Found the spark plugs fouled. Changed plugs and started up fine.

Probable root cause of problem is crankcase oil is slightly overfilled and oil may have entered cc breather tube. Combine this with engine tilted up when towing in rough weather (same arctic front that blasted through the US this week).

Service man tells me they prefer to keep dipstick level about 1/2 or 3/4 max.

Live and learn...

 

[Eagle180]

Re: yamaha 2008 115hp starting problem

You said something about crankcase overfill... you need to search this forum for "making oil" issue and read up on the oil levels in these 4 strokes. You can also google "yamaha making oil" and get several hits that discuss this issue.

I experienced the oil level rise in my Yamaha 115 4stroke and it took a while to narrow the problem down. There are several things you probably need to have checked and also there are ways to 'run' that outboard at the end of the day if a person does a lot of trolling during the day.

Anyway, search this forum and google the phrase up above and you will have some interesting reading to do.

Good luck

 

[99yam40]

Re: yamaha 2008 115hp starting problem

Thanks for the help.

Yamaha service came in today. Found the spark plugs fouled. Changed plugs and started up fine.

Probable root cause of problem is crankcase oil is slightly overfilled and oil may have entered cc breather tube. Combine this with engine tilted up when towing in rough weather (same arctic front that blasted through the US this week).

Service man tells me they prefer to keep dipstick level about 1/2 or 3/4 max.

Live and learn...

I have read a lot of posts about motors making oil and people finding their motors way over full when they checked the oil , but none of them said anything about fouling plugs because of it. You may have other problems, so keep an eye on your motor