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honda 30hp carb issues

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dandaman

New member
I have a 96 30hp honda on a 16ft skiff
The motor sat for a couple years while boat was repaired
I pulled carbs and tore um down soaked um in gas blasted um with air and a can of carb cleaner each and put um back together with new gaskets
It ran fine in the yard but under a load on the water it starts good but stalls when powering up
if i do get it up it runs good wide open for a few minutes than bogs down and runs ruff
I replaced the fuel hose, bulb, gas tank and put fresh gas in but it did not help
about 5 years ago i cleaned the carbs the same way and it ran great until the boat sat for repairs
What am i doing wrong
Does the jet have to seat in the nozzle a certain direction to allow holes to spray properly(maybe I just got lucky last time)
Should i soak um in something else ?maybe a ultrasonic hot water bath
Am i totally off could it be a fual pump it seems to be working?
Thanks in advance
 
Squeeze the fuel bulb to simulate the fuel pump. It no change...not the fuel pump.

You did not say anything about changing the spark plugs. Could be a fouled plug or a plug that is breaking down.

It most likely is in the carbs. As the engine boggs down, tickle your choke and see if the engine picks up. It so...carb job time again'

If you did not flush the fuel lines on the engine, you may have picked up some debris and it got caught again in one of the carbs.

Soaking in the ultrasonic cleaner with the proper solution is the best way to clean the carbs. Spray through all the passages and blow them out.
Make sure the idle jets (long skinny tube) is clear. These always get plugged. If it is really plugged, it sometimes is best to install new ones. The older ones like yours, sometimes develop cracks in the tube or at the tube connection to the larger section.

Make sure that the idle and transition passages are clear. Those are little holes in the top of the chamber just in front of the butterfly. The one hole behind the butterfly is the idle port. You should use something fairly non toxic to spray through them to check. Slightly screw in the idle mixture screw, put using the little straw that comes with brake clean or similar solvent. Stick the straw all the way up into the hole that idle jet (long skinny tube) goes into. Spray the solvent and watch the little holes. There should be a nice spray coming out all of the holes. If not, take a small wire and clean out the holes.

Also make sure all the air intakes are clear.

The idle mixture screws should be initially set at 3 turns out.

As for having the nozzle is a certain direction. It does not matter.

You should then vacuum balance the carbs. If you do not have a set of vacuum gauges, then at least try to put the carbs back into their original position.

Mike
 
Mike thanks a lot for your advise
So far I've cleaned the plugs but not replaced
All the fual lines leading to the fuel connect at engine are new I'm in the process of replacing all lines inside the coaling now
I have soaked each carb in a proper carb solvant the kind in the gallon can from autoparts store
And have blasted all with air again and have noticed a little gunk has come out so it appears to be working
If I use an ultrasonic wash what solution should I use?
Also I have cleaned the 4 little holes but haven't noticed anything coming out of them yet guess I have to seal off other holes by maybe reassembly and then try spray test
Also broke off 2 of 3 main jets on disassembly they are junk had to drill um out and retap ordered new ones so well see
 
Also noticed all 3 idle jets we clogged so I used wire to clear them.
I can see thru them all now so I hope its ok to reuse them
I cannot see any cracks
Thanks again for your advise Mike
 
Also noticed all 3 idle jets we clogged so I used wire to clear them.
I can see thru them all now so I hope its ok to reuse them
I cannot see any cracks
Thanks again for your advise Mike
 
To check your idle/transition passages (5 holes)...put the idle mixture screw in...but just screw it in a little. Take some brake clean, wd40 etc with a long plastic straw and put it up into the upper part of the carburator when the long idle jet seats. Block off the air intake with your finger and spray the brake clean and watch the holes. You should see a good even spray coming out of the holes. It not, they need more cleaning.

As for the ultrasonic cleaner solution. Check with the manufacturer of the ultrasonic cleaner and go by their recommendation.

Mike
 
What a great forum took your advise again mike and apon closer look i found cracks in all 3 of the idle jets at the bottom end
Thanks so much I would have never noticed them on my own
I will be ordering 3 new idle jets in the morning
I sprayed the carb cleaner as you directed and it looks as if all 4 holes are clear on all the carbs as is the single hole lined up with the mixture screw
If anyone else is following this thread let me just say the cleaning process was very time consuming but really not all that costly maybe 30$ in cleaner so far
I found an ultrasonic wash at a local toolhouse for $40 and im picking it up tomarrow and im going to dip the carbs anyway
Again many thanks Mike you have really helped me out and I probably wont be any help to you troubleshooting any honda issues but im pretty sure my honda can put us on some fish if your ever in the Savannah area;)
 
Just a followup for anyone with the same problems
I finally broke down and got an ultrasonic cleaner (about$75)
Pulled the carbs and put them in the cleaner for a few cycles and im running good as new
The cleaner is handy and ive used it on a lawnmower carb and a chainsaw since
Wish i had one years ago its already paid for itself
Oh guys it will really shine a wedding ring as well (a major selling point for the wives)
 
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