Logo

Honda bf75a 2006 running on 3 cylinders

Dwaine

New member
Hi ive just serviced my carbies, it appears to be only running on 3 cylinders.ive replaced the spark plugs.i get spark when i removed the plug from cylinder .and have swap the leads an still get nothing from particular cylinder.i also have tested when outboard is running.remove lead from dead cylinder and no change to rpm. How do i go about fixing this and where to start??
 
Sounds like you still have an issue with that carbie, if you have spark to the cylinder then I would go back to the carb. I will make the assumption you have great compression in all cylinders, if you haven't done a compression check, I would recommend that. But pretty sure you still have an issue with the carb.
 
Sounds like you still have an issue with that carbie, if you have spark to the cylinder then I would go back to the carb. I will make the assumption you have great compression in all cylinders, if you haven't done a compression check, I would recommend that. But pretty sure you still have an issue with the carb.


Eneusis thank you for your reply.
i plan on doing a compression check. what would be the process of checking the carbie again.? Just remove the drain plug or full strip again?
 
Missing at idle or all speeds? Typical carb issue would be missing at idle and kick in and run smoothly at higher rpm. Complete misfire indicates ignition or mechanical problem unless for some reason the offending carb has no fuel in it at all.
 
To run a compression test, remove plugs, pull the kill switch, insert the compression gauge into the cylinder, turn the throttle to full wide open throttle, then crank about 5 revolutions/cranks till you see the needle stop. Then repeat for each cylinder.

I will repeat the test on each cylinder about 3 times to get an accurate reading. Right down the PSI for each test on each cylinder. Any that are not inline with each other within 5-10 PSI will identify an issue with that cylinder.

Its a good thing to do so you know your engine is healthy.

But I still think its carb related and your float is stuck not letting any fuel in. Especially if you have spark to each cylinder.
 
Last edited:
Hi ive done a compression test... at ifle i get 105psi for 3 of the cyclinders and 75 psi for number 2.checked carbies via drain hole and there is fuel in there...
 
Did you run that at wide open throttle? If so, then I would run a second test just to be sure, I usually run each cylinder three times and record them all for comparison. That compression is not good, and most likely your issue.
 
Back
Top