Outboard issues

[patbratton]

I have a twenty year old Honda BF8A outboard that is refusing to start. It seems like an electrical problem, maybe coil. To me outboards are like sports cars, they need mothers. Do I learn every nook and cranny in this thing like I did on my '63 Dodge Dart (new nylon distributor drive gear every 30,000 miles) are do I pop for a new 8 HP Honda and drop $3,000? I only use the motor for entering and exiting the Marina. It doesn't take much to push my little Hunter 240. I could get by with a trolling motor. Brain storming is welcomed.
OK, this has now become a macho thing. I can't believe that I have been sucked into working on this engine. I have the wiring diagram and it shows the lanyard kill switch and the neutral position switch. I had already checked for spark so I am pretty sure it is not a fuel issue. There was no water in the fuel filter ( which i flushed). I had also changed the spark plug. I will go back up today and hang off the transom and see if I can ohm out the components.

Well, both the Kill Switch and the Neutral Switch have checked out. They had insulated snap terminals that made them easy to ohm them out. I also checked the circuit to ground. I drained the carburetor, re primed, and tried again. I had checked the spark plug yesterday (I did discover that I have two spark plugs). I hate to start just buying ignition parts but substitution is the only way I know to troubleshoot it any further. It usually is the last and most expensive component that fixes the issue. I also found the lever to unlock the outboard and swing the prop out of the water. Zoltan (previous owner) said that he only used non ethanol fuel. I am impressed with the entire Honda package, engine, fuel line, and fuel tank.

It looks like the issues is probably the coil. Having the model and serial number I was able to navigate the extensive Honda Parts webpage and determine the exact part number for the coil assembly and the CDI. I was able to order to coil from Amazon and am waiting for delivery. In the mean time I will continue to outfit the galley with equipment.
10-16-2021 My engine continues to torment me. I replaced the coil and still to spark. CDI on order and service manual from Honda Marine also. Detailed report to follow.

 

[Timm R Oday25]

My experience would tell me to figure out why you are aren't getting spark . This time of year demand for outboard repairs slow . Speaking as an owner of a '66 Coronet convertible , we need to keep this stuff running !!

 

[Calif. Ted]

Checked for spark from the coil ? remove wire, have someone you don't like hold it near sparkplug terminal and pull the rope, should see a spark or your friend jump.
Check for spark at the plug ? pull spark plug, with wire attached ground the plug and pull rope, should see a spark.

 

[Rich Stidger]

I always start by determining if the problem is fuel or spark. Squirt some starting fluid into the carb. If it starts and run for a few seconds until the starting fluid is used, then the problem is NOT spark. If no start or kick, then continue to diagnose the spark.
Removing the plug and connecting or holding the plug to the block while pulling on the start cord is a good starting test. If you see a spark and it is BLUE and NOT YELLOW then you may not have a spark problem.
Unfortunately, under a plug under compression may not spark if the coil is weak. So you need to put a spark gap tester in series with the plug with the plug in the engine. The spark gap is adjustable and it will show a spark with a plug under compression. If you have a spark, then you can believe that the problem is not ignition.
If you have spark and it will run on starting fluid but not on the tank gasoline you need to check for a plugged filter, air leaks in the fuel hoses, and the presence of fuel in the carb bowl. A sticking carb float valve will keep fuel out of the carb very well.
If you have confirmed that you have a quality spark and that it will run on starting fluid, and the fuel delivery system of filters and lines are good, then I pull the carb and install a rebuild kit.
I hope you are using E0 gasoline and not the E10 garbage that is sold for cars. Aluminum carbs do not do well with gasoline with ethanol.
Good luck. It's not rocket science. You just need to divide and conquer.

 

[Stu Jackson]

Rich's right, you need to find out why it doesn't. In addition to his advice, if you have a kill switch on the engine, check it out, too. I once had a kill switch wiring go T.U. and stopped the engine from starting. Good luck.

 

[patrickfarley]

I have a BF 75 Honda engine 7.5 horsepower. I had an engine problem it was not the spark. The problem was fuel delivery. When I cleaned the carburetor it still didn't work. I had to clean the carburetor and run a tiny wire through every channel. I found a bug wing that would fold down and extend at different times. Every time it extended it would kill the engine. Good luck.

 

[Rich Stidger]

I have found that an ultrasonic cleaner is effective in cleaning the small passages in a carb. Fill it with carb cleaner, let it soak overnight, and then run it for 30 minutes.
If it is your wife's cleaner for her jewelry and she catches you, don't tell her I told you to do this.

 

[Ken Cross]

My honda issues stemmed from rinning car fuel in the engine. I pulled the fuel bowl and found all sorts of stuff in the bowl. Because I was out for a several-week cruise I used what I had (WD40) and hosed out the carb and it's run like a champ since. I also no longer use anything but methanol-free gas in it.

 

[chip veres]

Use your ohmmeter to test the windings of the pulser and ignition coil. Pulser and ignition primary should be 1 to 100 ohms. Ignition secondary should be higher than that, maybe 1000 to 10000 ohms. Any coil is completely open and you have found the problem.

 

[patbratton]

I did not know that. thank you

 

[JeffD]

You probably already did this, but make sure the oil is full. The BF8A has some kind of oil level switch (shown in your diagram) and it won’t run if the oil is low. I guess the oil level switch could be bad too.

I found this out the hard way once, when I couldn’t get my Honda generator running. Turns out, the last time I changed the oil, I under filled it. I topped off the oil, and it started right up.

I have an old BF8A too - 2006. Good motor, has been quite reliable for me, but yea, when it doesn’t start, it can be quite frustrating! I feel for you!

 

[patbratton]

I disregarded the oil switch as I thought it was only for the light. I will pursue it.

 

[Benny17441]

Three things necessary for an engine to start. Compression, a timed spark and air/fuel mixture. Compression is easy to check, pull the cord and feel the pulsed resistance. If no resistance check head gasket, valves in a 4 stroke or piston rings. To check for fuel flow crank the engine a few times and remove the spark plug, it should be wet. If dry there is a fuel flow obstruction or a failed fuel pump. Electrical remove the spark plug, connect the wire and with insulated plyers hold the body against the cylinder head and crank the engine, you should be able to see the spark jump. Bad coils usually don't spark, spark very weakly or spark noticeably erratic. If you have all three elements but still does not start then the logical point to go is the carburetor as it is likely not producing the desired air/fuel ratio. Check the choke operation for cold starts and disassemble and give it a thorough cleaning. For a badly gummed carburetor replacement might be the best solution.