Honda BF 90 shutting down . Please Help

[Big Wayne]

I have a 2006 Honda BF 90 4-stroke. One day I was out in the bay running at full throttle and the motor died as if it the ignition was swithed off. I checked and it was getting fuel. Then I checked the ignition and it didn't have a spark. Waited about 30 minutes and it fired right up.
I took it to my local marine mechanic and they ran all the tests on it and said they couldn't find anything wrong. So I took it back out on the bay and it ran fine all day. Then as I was running about 3/4 throttle, it died again. Waited 30 minutes and it fired up. I started back toward the boat ramp and after running about 10 minutes, it did it again. I waited for it to cool down and finally made it home. This time I decided to take it to another mechanic a few hours from my house. They ran it for over an hour on a dyno under various loads and couldn't find anything wrong. So I took it back to the bay and guess what? It did it again.
Has anyone heard of this problem? I only had a 3 year warranty so that's over. I know it's a heat related problem causing it to loose all ignition. I can't really afford to play swaptronics with parts that costs around $500 each and electrical parts are none refundable. I hope someone out there can point me in the right direction. I have a boat that I can't use and can't get fixed because they say nothing is wrong. Thanks

 

[AGENT 37]

Re: Honda BF 90 shutting down . Please Help

Check out your kill switch wiring before you start swapping electronics. Make sure that your switch is not partially shorting out.

Might also check the wires for your "key on" for the ignition system.

Could possibly be that spray is shorting out an exposed wire or that jarring from wave action is working a bad wire circuit.

Spray and wave impact aren't being simulated out of the water.

 

[Big Wayne]

Re: Honda BF 90 shutting down . Please Help

Thanks! I was thinking about that kill switch too. I'll straight wire it and take it out of the circuit. It's worth a try. It will be a few days before I can get back on the water, but I'll let you know what happens.

 

[Big Wayne]

Re: Honda BF 90 shutting down . Please Help

Took the kill switch out of the loop and tried it again. Same result--It shut down after about 10 min.

 

[hondon]

Re: Honda BF 90 shutting down . Please Help

An qverheat or low oil pressure situation will shut this engine down.Dynos are great in concept but are hardly the real world.When is the last time you did the water pump kit on this unit?

 

[matt.speedtriple]

Re: Honda BF 90 shutting down . Please Help

It sounds to me like your cdi pulser pickup coil is as fault. We have a lot of problems with certain bikes which have exactly the same problem. There can be a crack internally in the coil and as it heats up then the coil expands and opens up a gap where it`s broken and you come to a stop with a dead engine. Wait 20 mins for it to cool back down again and the connection is made again and your engine will restart until it gets hot. This can also happen with HT coils if you all of a sudden loose spark from a certain coil.

Hope this helps and your back up and running soon.

 

[wesman2]

Re: Honda BF 90 shutting down . Please Help

I have a 2003 BF15 which behaves in a very similar manner. On a hot day at full throttle under load, I lose power, it is like the throttle is reduced. If I take it easy I can make it back home. If I continue to push it, the engine will cut out altogether and will not restart for about 10 or 15 minutes. On a cool day or at low throttle the engine will run for days. I have taken the engine to three marinas and none have been able to identify the problem. I have even spoke with Honda about this with no success. To me it sounds like an ignition problem but I am not sure which component, CDI, Pulser, or ignition coil to replace. I am so frustrated with this engine that I would like to get rid of it but in it's current state I won't get much for it.

If anyone has any recommendations on which part(s) I should replace, I would appreciated the advice.

Thanks,

Wes

 

[fishskiff]

Re: Honda BF 90 shutting down . Please Help

I just replaced my cdi module after my 90' bf15 was having similar symptoms. I was convinced when I could tap on the cdi box with a screwdriver handle and the motor would die. This was also difficult to diagnose where all "honda Dealers" i took it to told me that ignition problems were very rare and I had to figure it out myself. A year and a half later it's fixed and runs perfect. Hope this helps.. fish on