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Oil discharge from Carbs PLUS Vacuum Pressure HELP - Honda BF40

Are you sure your not looking at the metric valve lash? From what I am seeing the intake should be between .005-.007 inches and the exhaust are between .008-.010 inches the way your adjusted just seem way too far making the tappet noise? The metric measure is intake .13-.17 mm and exhaust .21-.25mm it looks like your just adding a zero to the metric numbers.
 
kimcrwbr1 said:
Are you sure your not looking at the metric valve lash? From what I am seeing the intake should be between .005-.007 inches and the exhaust are between .008-.010 inches the way your adjusted just seem way too far making the tappet noise? The metric measure is intake .13-.17 mm and exhaust .21-.25mm it looks like your just adding a zero to the metric numbers.
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Here is a picture of the manual, maybe I am using the wrong manual or I am not converting something. After hearing it run though I agree its too open.

manual.jpg

Should these be sized to the lower, middle or higher end of the ranges? Do I just have the incorrect feeler gauge?
 
eneusiis said:
Here is a picture of the manual, maybe I am using the wrong manual or I am not converting something. After hearing it run though I agree its too open.

View attachment 16181

Should these be sized to the lower, middle or higher end of the ranges? Do I just have the incorrect feeler gauge?
Click to expand...

Boy.....After looking at that again I swear I saw another Zero in there, holy crap I must be retarded tired....Well, I guess its back to the adjusting the rockers again tonight!
 
Set them where .005 will go through and .006 will not you always adjust to the small number that way it will take longer before they go out of spec but yo can use the centyer number. The first set of numbers is mm and the ones in parentheses is inches. Be sure and adjust the valves before you replace the belt. If you do both at the same time and it then runs better you dont know exactly what the problem was for future reference.
 
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eneusiis said:
Here is a picture of the manual, maybe I am using the wrong manual or I am not converting something. After hearing it run though I agree its too open.

View attachment 16181

Should these be sized to the lower, middle or higher end of the ranges? Do I just have the incorrect feeler gauge?
Click to expand...

I can't tell for sure from the picture, but it looks like your feeler gauge set only goes down to .013". Make sure you get a set that has .005"
 
kimcrwbr1 said:
Are you sure your not looking at the metric valve lash? From what I am seeing the intake should be between .005-.007 inches and the exhaust are between .008-.010 inches the way your adjusted just seem way too far making the tappet noise? The metric measure is intake .13-.17 mm and exhaust .21-.25mm it looks like your just adding a zero to the metric numbers.
Click to expand...

okay I resized them check out the new video. Starts up, idles well I ran it for 30 mins in my driveway without issue. I would imagine that if it was a timing issue that it would be noticeable but belt is in great condition. New one is on the way regardless.

I am am still puzzled about the vacuum gauge and am thinking it may be faulty.


Not sure on on what is next. Thoughts?
 
Reading the sync procedure your not reading the actual vacuum pressure as much as the difference between the three carbs. As long as the difference is between .75 inches mercury you should be just fine. You cannot adjust the #3 carb so you make #1 and #2 match #3. From What I am seeing you should be good. Hopefully hondadude will chime in. It does look like the needles are alot more stabil with the final valve adjustment very little bounce in the needles.
 
kimcrwbr1 said:
Reading the sync procedure your not reading the actual vacuum pressure as much as the difference between the three carbs. As long as the difference is between .75 inches mercury you should be just fine. You cannot adjust the #3 carb so you make #1 and #2 match #3. From What I am seeing you should be good. Hopefully hondadude will chime in. It does look like the needles are alot more stabil with the final valve adjustment very little bounce in the needles.
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Hey,

yeah i resynced them and and they were not to far off. honestly it is running fantastic so I really don't see any issues. So it is comforting to hear you say that.

One funny thing about the carbs carbs on this is that the fuel needles on the upper sides of the carbs are typically adjustable and these are not. Anyway it's running smooth so can't complain.

i really appreciate you following this thread and helping me through this. I owe you a few cases of beer!
 
Are you sure it does not have the idle air needles? They call them the pilot screws on the upper left of the carbs. It says to preadjust them 2 1/4 turns from lightly seated. Adjust the idle speed with a tach and after a 10 min warm up adjust the #3 carb for the highest possible rpm and follow up with the #1 and #2 carbs and then set the proper idle speed. Just slowly turn it in until the rpm drops and back out. You will reach the point where the idle speed will only drop when you turn them in.
http://www.ebay.com/itm/Honda-OEM-M...ash=item35e8d029c7:g:gv8AAOSwymxVNpfg&vxp=mtr
I pulled up this part number not knowing the number of your engine you see it has the o-ring and spring I would look into it and see if that is another adjustment you can make.
 
kimcrwbr1 said:
Are you sure it does not have the idle air needles? They call them the pilot screws on the upper left of the carbs. It says to preadjust them 2 1/4 turns from lightly seated. Adjust the idle speed with a tach and after a 10 min warm up adjust the #3 carb for the highest possible rpm and follow up with the #1 and #2 carbs and then set the proper idle speed. Just slowly turn it in until the rpm drops and back out. You will reach the point where the idle speed will only drop when you turn them in.
http://www.ebay.com/itm/Honda-OEM-M...ash=item35e8d029c7:g:gv8AAOSwymxVNpfg&vxp=mtr
I pulled up this part number not knowing the number of your engine you see it has the o-ring and spring I would look into it and see if that is another adjustment you can make.
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It has them but like I said above they were not adjustable. That was the first step that I took in the carb sync process. The videos and instructions mshow an adjustable screw in the upper left which mine have but they are locked down in a slot unlike the others that I have seen. I played with them with the engine running and they can only turn a little and it doesn't make a difference. They have an "ear" on them that keeps them in place. I was kind of baffled myself.


I will I'll add a picture in the morning
 
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Your probably ok as it still has the factory setting keep an eye on your spark plugs. The insulator for the center electrode should be a nice toasty brown. If they come out a powdery white it is burning too lean and can burn valves and pistons.
 
I am pretty sure they just pry right off the needles but is it necessary? You would want to remove them for sure if you were rebuilding the carbs but your next step is to take it out and point the boat at the big part of the lake and go. All I ask is if you see someone in distress stop and lend a hand.
 
kimcrwbr1 said:
I am pretty sure they just pry right off the needles but is it necessary? You would want to remove them for sure if you were rebuilding the carbs but your next step is to take it out and point the boat at the big part of the lake and go. All I ask is if you see someone in distress stop and lend a hand.
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No sweat on that one, when I got the motor, I replaced the float needles and inspected them. I always help those in need on the water, so I got ya covered there!
 
kimcrwbr1 said:
I am pretty sure they just pry right off the needles but is it necessary? You would want to remove them for sure if you were rebuilding the carbs but your next step is to take it out and point the boat at the big part of the lake and go. All I ask is if you see someone in distress stop and lend a hand.
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UPDATE:

Took the day off fishing yesterday. The motor ran like a top, smooth idle, trolled endlessly without a hiccup, top end and middle range were solid! The addition per another post on here, of the Honda fuel water separator was also working beautifully. I am one satisfied Honda owner.

Thanks again for all the help!
 
Nice everybody should be able to do the preventive maintenance on their equipment out there you are the captain and the engineer. Good job.
 
kimcrwbr1 said:
Nice everybody should be able to do the preventive maintenance on their equipment out there you are the captain and the engineer. Good job.
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Also, forgot to mention/follow up that your advice on adjusting the rocker gap, did stop the oil blow by that I was getting in my muffler
 
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