Spark problem or Fuel???

[zanko]

Hello,

I have a BF9.9 Ithink its a 93. Iusually run it about 20 hours a year.

I bought this boat in 1997 used. Oil has always been kept fresh.

With clean plugs and last years fuel, I am having extreme difficulty starting the motor. after a while it will start, run for 30 to 40 mins till I turn it off but will not warm start again, or if it does its intermittent and not consistent.

The plugs look extremmely fouled after it is shut off mainly carbon as I had put some seafoam in the tank last year.

I usually store this boat for about 9 months out of the year, and I do not drained the carb from all the fuel.

I am puzzled if this a spark issue or a fuel issue.

When I take one plug out and connect the plug wire to it then ground it to the engine case and crank the engine I am not seeing any spark at all, do I need to ground both plugs to test this?

as for the carb mixture setting I am a bit unsure on where that needs to be. I have it about 3/4 ways in and it did start.

I had gapped teh plugs to .023 to .024 and there was no consistent results.

since I have owned it it has started every time without any trouble, so I am wondering if something is starting to go?

any help is appreciated..

 

[dummyman]

Re: Spark problem or Fuel???

Hi,
This seems to be a fuel problem. As in carburetted outboard engines you are not supposed to use very old fuel. Even if you have used fuel stabiliser they are not up to the mark. Do not forget to drain the carbs while storing for long. You may need a carb cleanup. The spark plug gap is too less. The reason for plugs not sparking is probably not putting the kill swich while cranking to do the spark test. Other wise your engines should be fine.

Cheers and good luck

 

[hondon]

Re: Spark problem or Fuel???

Stale or contaminated fuel pops to mind immediatly.These engines rarely have ignition problems and offer up very cold spark on crank over so it is hard to see.Idle speed is critical on these engines as well or you will get fouled plugs if you are set too slow or lugging the engine.That year old fuel has got to go.

 

[zanko]

Re: Spark problem or Fuel???

thanks for the reply, its not the fuel as it runs for good 30 mins, then if I wiggle the regulator it dies. if I move the regulator up or to the side a bit it does spark. It is not bad wiring as that would be constant. Gonna try a new regulator and see how it goes. Thanks, yes the fuel will get replaced but bad fuel cannot prevent spark.

 

[gss036]

Re: Spark problem or Fuel???

I was having problems w/my 1997 15 hp and got so flustered, I finally sold the engine and bought a Yamaha T9.9.
It definitely was something in the wiring/regulator, seems to be more and more of that same thing popping up here on this forum. Each of the modules runs about hundred bucks and I was not going to start flinging parts at it @$100 a pop and the local Honda shop wanted $100 @hr to work on it. It only cost me $1100 to swap engines w/selling my old one. Now I start all over with a new engine and a 6 year warranty.
I know that is not what you wanted to hear, but that's how I solved the problem.

 

[zanko]

Re: Spark problem or Fuel???

So I am back at this problem again as I never fixed it last year, and I wasnt about to go fishing and keep restarting the motor. Also last time I took the boat out was a year ago and anytime I hit over 1/4 throttle it dies, if I idle or stay under 1/4 throttle then it stays running, and wigling the CDI pack seems to start and kill it when wiggled the right way.



got the book and did the following tests:

Ignition coil test - ok
Ignition charge coil - ok
rectifier - ok
stop circuit test ok
stop switch test - ok
ran continuity tests on every lead from the CDI pack and all are good and solid

The issue is intermittent spark regardless if in idle or gear.

They only thing left is the CDI pack and the only thing the manual says about is that it will give intermittent spark symptoms. got one ordered so will see if this solves the mystery. I'll post back my results once new unit is in.

 

[zanko]

Re: Spark problem or Fuel??? SOLVED

Re: Spark problem or Fuel??? SOLVED

Replaced CDI pack and she runs like new, no stalling, no intermittent spark at all. Also replaced coil, plug wires,fuel filter and timming belt. This is a BF 9.9 A 93 motor.

 

[gss036]

Re: Spark problem or Fuel???

Again, thank you for letting us know. I suspect that was the problem with my 93-94 15hp Honda. I sold it and told the buyer what the problem was. Still never heard back from him so he must be a satisfied customer.