Logo

BF5A '1996 Honda 5hp 4 stroke Running Problem, Please Help

Ikonoclast

New member
Hello,

I recently got a '96 Honda 5hp 4 stroke that was sitting in a shed for the past couple of years. The previous owner said that before it was stored he had the carb replaced, I do not know why. Anyway, when I took it out on the water for the first time, it started on the second pull, sounded pretty good, but then abruptly died after about 2 minutes of running. After which, it would not start again for a while/a number of pulls, which made me believe that it was being flooded with gas, but each tiem I was able to get it to start it died after less than 2 minutes. Any ideas on what I should try? I am not particularly knowledgeable on 4stroke outboards, so it could be something simple that I am missing. Or it could be that the replaced carb is somehow faulty.

Thanks
 
Re: BF5A '96 Honda 5hp 4 stroke Running Problem, Please Help

Most likely the carb was replaced because it may have been cheaper to replace it than to have it fixed.

If a motor has been sitting in the shed, little critters like to get inside the vent tubes and sometimes even the carburators.

Check the crankcase vent hose on the port side of the engine that goes from under the flywheel down (vertically) to a hold in the lower casing. Pull it off and be sure that it clear of debris.

Also, be sure you are opening your vent on the fuel tank.

Make sure you have new gas.

Drain the old gas out of the carburator into a glass jar to be sure it is clear and has no water.

Mike
 
Mike,

I have cleaned out the carb, intake, fuel lines, and the fuel pump the other day. The only think I noticed was that the fuel drain hole at the bottom of the carb was clogged with debris, so I cleaned that out, but did not check to see if there was any water in the carb, will do this after the next time I get to run it. I will check the crankcase vent today. Hopefully I will have a chance to go out on the water and try it out this next weekend and will deffinitely report back with an update. Thanks for your help, Mike.
 
Was there debris in the actual drain or just the drain tube? If there was debris in the drain, then there was probably debris in the carburator bowl. You said you cleaned the carb...did you take it apart and clean it?

Mike
 
The debris was lodged in the actual drain at the bottom of the carb bowl. The drain tube was clear. Yes I took apart (as far as I could) all the parts I listed before, and cleaned them.

Thanks
 
Ohh one more thing that I forgot to mention is that when I was taking the motor apart I noticed that the little paper-like gaskets between the major parts were brittle and some broke apart when I was taking the motor apart. So I will be replacing those.
 
So I finally got the replacement gaskets. Put it all back together. Added new oil. Too it out on a boat, and it started nicely and would run in neutral for up to 90 seconds and then would slowly die out. When I would put it into gear it would cut out almost instantly. I had someone (who used to work on outboards) take a look at the carb and he said that it looks like there's a "varnish-like" coating on the inside that he could see and smell. He said that since some of the holes are like 1/38th of an inch wide, a little bit of residue can make a bid difference in getting the right fuel-air ratio. So he advised me to clean out the carb with carb cleaner and the n try it again. Going to do that today and should hopefully have a chance to egt on the water during the weekend.

Thanks
 
After you clean the carb, if you are still having the same problem, make sure the vent on your fuel tank is open.

Also, try squeezing your fuel bulb and keep it hard to see if the running improves. If so, you may have a fuel flow issue from your tank to the engine or may even have a bad fuel pump.

Mike
 
Mike,

I have tried to keep on pumping the bulb, but it almost seems that when I do that it floods the engine. I would think that the little plug in the carb bowl that is pushed up by the float is relatively easy to overcome by pumping the bulb a good amount. But I will try to add light but continuous pressure when I go out this weekend. And yes, I keep the vent on the fuel tank open.

Thanks for your advice!

Can't wait to get this thing working properly, crabbing season is right around the corner, for where I go. Pretty excited to get some crab.
 
As you correctly stated earlier, the float valve ("little plug") can't take much pressure so the pump only needs to create a bit of flow. I don't have the manual for your motor but they typically say; "remove the fuel line from the pump to the carburetor and place the end in a suitable container." "Disable ignition with the kill switch and observe that fuel flows into container while cranking engine with recoil starter."

I call it a "gurburble" that comes out. If you want to be a bit more scientific, you will need a 0 to 15psi fuel gauge and attach it to the pump outlet. The pump should "dead head" at around 7 psi. with anything under 3 psi being suspect.
 
Last edited:
As you correctly stated earlier, the float valve ("little plug") can't take much pressure so the pump only needs to create a bit of flow. I don't have the manual for your motor but they typically say; "remove the fuel line from the pump to the carburetor and place the end in a suitable container." "Disable ignition with the kill switch and observe that fuel flows into container while cranking engine with recoil starter."

I call it a "gurburble" that comes out. If you want to be a bit more scientific, you will need a 0 to 15psi fuel gauge and attach it to the pump outlet. The pump should "dead head" at around 7 psi. with anything under 3 psi being suspect.

I bought a new engine & stopped after a few hours. On stripping the carb, it also had the waxy gunge mention above. Cleaned it thoroughly & though that would be it fixed. No, spent the whole season breaking down after about 30min to 1hr running, about 20 times. I would strip the carb (I was getting expert at it by this time),no sign of any problem (I'd previously check all fuel parts) reassemble, & it run fine until the next time. I eventually notice it was flooding so I removed the float (initially reluctant as its held by a pressed fit pin) & fuel control needle, which looked fine, nor could I see any debris, replaced the assembly & the engine has run without failure since. My conclusion, sticking needle, or maybe lodged debris that wasn't being removed by blowing on earlier failures.
 
Back
Top