Pull the carbs off again?

[bcj.jones]

Just cleaned the carbs on my 89 50 horse johnson. Ran great the first couple times I took it out after. Now it bogs down at w.o.t

Before I pull the carbs back off and rear clean them, is there anything else I should check first?

Little back story. Motor/boat is new to me. Rebuild the carbs only because it came with kits. No problems before. The motor ran great on the 2nd time out all day until I got back to the boat ramp. Initially thought I was running out of gas, still have 3 gallons though. Motor runs great on muffs. In gear and neutral will rev great out of the water. Took it back out today thinking things were fine and the same thing. Another weird thing is ever once in a while for about 15-20 seconds it'll run w.o.t up to 30 mph at 5500 rpms and hold it for that 15-20 seconds and then start to bog and surge.

Definitely carbs? Or something else? Vent is open on the fuel tank

Thanks for any recommendations

 

[flyingscott]

Is the vro still connected.

 

[bcj.jones]

I honestly don't know how to tell. The previous owner said the VRO pump was bad, so as well as I just pre mix the fuel.

I'm assuming the VRO could have an affect on how it runs?

 

[Bosunsmate]

How do your plugs look?
I wouldnt rev it at the moment as if it isnt getting fuel/oil to a cylinder that cylinder will be running dry, they can run on only one cylinder when on muffs.
Although i suspect you would get a backfire.
Also try a drop test on muffs. Pull each plug wire off with pliers while its running, see if pulling off a wire doesnt make the engine speed change much, that means that cylinder isnt working properly. Each cylinder should be pulling roughly the same as the others

 

[Crosbyman]

gas is clean ?? no water condensation ?

 

[racerone]

Sounds like it is ruuning on one cylinder and ocasionally the second cylinder kicks in.----Does spark jump a gap of 7/16" or more on both leads , yes or no ?

 

[tommarvin]

You need to clean and maintain the vro every year.
There is a filter in there somewhere, that needs to be changed , never had a vro.
My gut says it lack of maintenance that stops VRO's

 

[WhiteRice]

Still learning mine but I ran into a similar issue a few months back. Double check your floats and float needles. I was experiencing the same thing and was able to call the shop while on the water and displaying what you are describing. He said I may have a stuck needle or faulty float that was causing that bowl to flood and, in turn, flood that cylinder. He had me clamp the fuel line going to that carb when the motor started to bog down. about 5-10 seconds later, the RPMs started to come back up. I was essentially keeping the carb from flooding. Came back in, purchased new float needles and seats and that fixed it... (until I started having other issues not related to the carbs... lol).

 

[Silvertip]

Surging at wide open throttle is a sign of insufficient fuel delivery. Especially since you say it runs fine in neutral and not under load. This has a number of possible causes: 1) fuel pump has gone weak 2) restriction somewhere in the fuel line/tank. If the restriction is between the primer bulb and the engine, squeezing the bulb when the engine bogs may allow the engine to pick up and may also indicate the pump is bad. If there is a restriction between the bulb and pickup in the tank, the primer bulb will be sucked flat or partially flat. 3) Improper float settings in the carbs. 4) Fuel bowls being emptied faster than they are being filled. If you are using a plastic portable tank, drain the fuel through cheese cloth and check for bits of plastic. I've seen many of these tanks brand new with a bunch of plastic in them from the manufacturing process. One of those tanks was my own.