Logo
FULL SITE MENU

Need Help

H

hbone

New member
I have a Honda 2004 BF25D. It hasn't been run for over a year.
I cant get it to run. Did a carb rebuild and still no luck.
When i spray carb cleaner it will fire just fine but then cuts out.

I know gas is getting to the bowls.

Any suggestions?
 
My first recommendation, since you are trying to do the carbs yourself, is to purchase the Honda Carburetor Manual. https://www.amazon.com/Honda-Marine...TF8&qid=1470885218&sr=1-1&keywords=carburetor

As you can see from the cover, it shows you what each passage does at various stages of speed of the motor.

Since the engine ran on starting fluid, it points to the carburetors.

I know you said that you cleaned them...but it is time to completely disassemble and really clean them...

Did you remove the jet sets (long skinny tubes going up inside the carburetor? Can you see through them? If not, it is best to replace them. You can get them to the point where you can see through them, but since the hole on one end is smaller than the hole on the other, there is an obvious ledge inside the tube (which you can not see). You can also...not see it there is any dirt, etc trapped in that corner. If you do not get it out, you will be taking the carbs apart again.

Did you make sure that there is flow through the idle and transition ports? The tiny pin holes at the top of the rear of the venturi.
If you use a can of brakleen with a straw, you put the straw up into the hole at the top of the venturi where the jet set goes in. If you spray into that hole, fuel should come out a hole in the front of the carburetor (the idle air jet) and may dribble out the 4 or 5 pin holes at the top of the rear of the venturi. If you put your finger over the hole in the front of the carburetor where the jet it, the brakleen should shoot out of those little pin holes. If it does not, then that passage needs more cleaning.

As an fyi for any reading this, with the butterfly close, there is one pin sized hole visible. That is the hole that supplies the fuel to the cylinders for idle. The 4 that you can see when you open the butterfly, provide the added fuel to transition to faster speed. Once you get to full throttle all the pin holes supply fuel as well as the big tube around the jet set. So, I hope you can see how important those little pin holes are!

Your other issue is probably the bowl on #1 carburetor. There are passages into the bottom of the bowl that feed fuel to the bystarter circuit. If they are plugged, the motor will not start.

While we are on starting, check the number that is etched into the bowl just above it little drain nipple. If it is 75 and the bystarter letters start with DE or DR, then you should consider changing the bowl and the bystarter. It will make starting much easier The new bowl and bystarter will provide a richer mixture for starting. the new bystarter number is 16130-ZW2-F01 and the Float Chamber set (includes bowl o ring and drain screw) 16023-ZV7-F01. The new bystarter lettering will begin with HH and the new bowl etching is 70.

Hope that gets you started on round two.

Since the motor has been sitting, critters like to build nests in unusual places....so....
A couple more things to check....

1. Make sure the small black tubes running vertically behind the carburetor are clear of any muddobber nests. Those provide venting to the carburetor bowls.
2. Also, check under the cam pulley and the flywheel to make sure there are no nests there, as well. A nest in the wrong spot can cause the timing belt to jump time.

Mike
 
Ok I have replaced jets in carb and made sure all jet operate.

Im getting Gas to the bowls.

Please explain more on the #1 Bowl.

John
 
There is a small hole in the bottom of the #1 bowl and the fuel goes from that hole over to the larger hole, which feeds the long narrow tube up to the bystarter. At startup, the fuel flows up that narrow tube and is blended with the appropriate amount of air and then that fuel/air mixture travels to all the carburetors to enrichen the startup. As the motor runs, the bystarter heats up and pushes its needle slowly down to close off the top of the tube. You will notice that it is working if the engine starts at a fairly high rpm, then gradually settles down to the standard idle rpm...which should be around 950 to 1000.

The carburetor manual, that I mentioned, goes into a much better explanation, with colored pictures indicated where air, fuel or a mixture of air and fuel are flowing.

After you get things running, finish the process properly, you need to vacuum balance the carburetors. The manual also explains this in great detail.

Mike
 
Mike told me about the carb manual a few years back. I have NEVER been sorry I bought one.
I had been SUCCESSFULLY rebuilding carbs....including 4bbls for cars and I/O V-8 boat engines for years. But there was still PLENTY of info in that book that had me being an old dog learning new tricks when it came to servicing these little Honda carburetors.

A MUST HAVE, in my opinion, if you're going to be working on those Honda carbs.

Thanks, Mike, for sharing all your secrets over the years. You sure have made ME a better outboard tech!
 
Back
Top