Yamaha F115 hard starting once it has been run.

[killoy]

I have a 2001, Yamaha F115 with 1011 hours. Three times this summer in the last 40 hours of using it has been very hard to start. This happens after running normally and turning the engine off and trying to start within 30 minutes of stopping. Today I tried a new primer bulb, portable gas tank with fresh gas but could not get it to start. Also today when it would not start the warning horn was sounding while the engine was turning over. Six hours later I was testing the flow on the fuel pump and the engine started right up. Fuel flow was good, I connected the original fuel lines, and ran the engine for 5 minutes on the trailer with no problems. Any ideas of what to test or look for would be greatly appreciated.

Thanks,

Kevin

Problem solved. Answer posted on #26 in thread.

 

[99yam40]

Re: Yamaha F115 hard starting once it has been run.

on some motors the alarm sounds when kill switch is pulled and key is turned to start,could be a wire is grounding out
but not sure if your does. easy to test it though

 

[Pas Bon]

Re: Yamaha F115 hard starting once it has been run.

My 2002 F115 will not start right up sometimes after I shut it down after running (if I shut it down right away) So I have started to let it idle for a minute or two and then kill it. Once when it happened I got an alarm just prior to shutting it off and so I quickly killed it thinking there was a problem, then it wouldn't start. I did change the water pump after that, and I haven't had anymore problems but like I said I always let it idle for a minute or two after running it for a while. I think there is a sensor in there somewhere that thinks it shouldn't be allowed to run. BUT THAT IS JUST A GUESS

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

After some troubleshooting I have decided that the water pump is due for replacement. I think it would pump fine when cruising, but after cruising and then slowing to idle for a few minutes it was not pumping enough water and cooling was not enough at the fuel rail causing a vapor lock to occur. I have finished a complete water pump assembly. I will run it this weekend and let everyone know if the problem seems to be resolved. I hope I am correct.

Thanks,

Kevin

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

I installed the complete water pump kit. Cruised for 2 miles, idled for 5 minutes, ran for 6 miles and turned the engine off. Tried to start ten minutes later and the engine would only turn over and not start. Should I be looking for an electrical or fuel issue?

Thanks,

Kevin

 

[99yam40]

Re: Yamaha F115 hard starting once it has been run.

my computer link to my Cristal ball is not working , so you will have to test things to see if you have spark when it will not start

 

[Toddboat]

Re: Yamaha F115 hard starting once it has been run.

It could be as simple as your starting procedure. Maybe you're priming it when starting it while still hot? That could flood it and cause similar symptoms. If it's just flooded, it will start a day later after the fuel evaporates.

 

[Pas Bon]

Re: Yamaha F115 hard starting once it has been run.

Did it ever start back up? if so how long did it take?

BUT you got me....like I said once I started letting it idle prior to turning it off haven't had a problem.

If you figure it out PLEASE let us know what the problem is!

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

The engine started fine the next morning. I bought a fuel pressure tester at Harbor Freight, attached it on the Schrader valve, left the cowl off the engine and cruised about 4 miles between 3700 and 4100 rpms. The pressure was between 30-32lbs the entire trip, cruising or idle. I turned the engine off. Cranked fine when I tried immediately and after letting it sit for 10 minutes. Maybe running with the cowl off kept the possible failing part cool enough so it did not fail. I am going to try to duplicate the problem today. If it fails, I have the fuel pressure gauge and spark tester to try to determine if it is fuel or electrical related.

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

I removed the VST tonight. The filter had a slight amount of debris. Maybe the reason fuel psi was running 30-32. This is the first time it has been taken apart and now has 1013 hours on the engine. I cleaned the filter and the tank. I will mount everything back on the engine and test it this weekend to see if I can duplicate the problem.

 

[Pas Bon]

Re: Yamaha F115 hard starting once it has been run.

I removed the VST tonight. The filter had a slight amount of debris. Maybe the reason fuel psi was running 30-32. This is the first time it has been taken apart and now has 1013 hours on the engine. I cleaned the filter and the tank. I will mount everything back on the engine and test it this weekend to see if I can duplicate the problem.

How long did it take you to do that?

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

I took my time removing because this is my first time. One hour to remove, one hour to clean VST. One and half hours to reinstall back on the engine. The hardest part is the removing bolt at the bottom of the silencer and intake manifold. One other tip, remove the bottom "L" bracket that holds the intake manifold to the engine, this will make it easier to remove and reinstall the complete assembly. It was easier to perform than I had expected. Good Luck.

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

I have also ordered the diagnostic cable and YDS software so I can see if there are any error codes. Engine takes 2 or 3 seconds to start. Rodbolt (Yamaha Master Mechanic) and others have said this means there are error codes. I will report back with the error codes if they exist.

 

[Pas Bon]

Re: Yamaha F115 hard starting once it has been run.

Thanks!!!

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

I received my Yamaha Diagnostic System. I have attached four pictures of info it read while running.


The shift position switch reads "irregular" does anyone know what this means.

Thanks,

Kevin

 

[Pas Bon]

Re: Yamaha F115 hard starting once it has been run.

Hopefully someone can tell you what that shift code means.


How much was that cable and software? and where did you get the cable, and software, and did you need anything else?

 

[99yam40]

Re: Yamaha F115 hard starting once it has been run.

possible revving in neutral or died while in gear, not sure, but you can test it to make sure it is working properly

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

Today I cruised 15 miles between 4000-4500 rpms. Boat sat one hour. cranked in 2 to 3 seconds. Ran 7 miles and tried to crank after 15 minutes, would not start. Five minutes later it started. Cruised seven miles and tried to start after 15 minutes off. Would not start but I did see spark using a spark tester. Waited 45 more minutes and it started. I am not sure what to check next. Even when it cranks, spark at the tester is not seen for 2 to 3 seconds. I seems to be something failing when hot. Coils, stator, computer. Can anyone tell me what to try next.

Thanks,

Kevin

 

[99yam40]

Re: Yamaha F115 hard starting once it has been run.

Would not start but I did see spark using a spark tester. Even when it cranks, spark at the tester is not seen for 2 to 3 seconds.
Kevin

May need to explain better when there is spark and when there is none

 

[killoy]

Re: Yamaha F115 hard starting once it has been run.

I see spark using a spark tester after 2 to 3 seconds when the engine cranks and starts right after I see the spark. I see spark in the same way when the engine is warm and cranked repeatedly but will not start. After the engine cools, it starts every time. How do I test the coils or stator? Maybe when hot they are not putting out enough to start the engine. Can I check the fuel pressure regulator?

Thanks,

Kevin