80hp Johnson now BOGS at WOT!

yorab

yorab

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Re: 80hp Johnson now BOGS at WOT!

Don't sink it!

I can't help with the link n' sync because I don't have my manuals with me. Besides, there may be some ignition changes from 1963 to 1967. If nobody has a manual for your year, you might have to bite the bullet and get a manual.

There is always a slick behind the motor. Kind of embarassing sometimes... But anyway, you could be getting proper fuel to one bank of cylinders and not the other bank, thereby causing the lean sneeze. Unburnt fuel/oil will still emanate from the cylinder bank that is getting enough and cause the wonderful glossy sheen behind your boat.
 
BonairII

BonairII

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Re: 80hp Johnson now BOGS at WOT!

How do I figure out which bank is running lean? Assuming that that is what's happening. I do notice that the motor seems to idle a bit faster and if I back the throttle all the way down, it starts bucking and stalls.
When I was running on only 2 cylinders, the motor would run great at very slow speeds.

I'm too broke to get a manual right now...barely have the cash to fill the fuel tank. I took in one of my son's friends a few weeks ago(abusive parents) and I have an extra mouth to feed while the courts try to make his parents pay some kind of support. Pretty sad for the kid, his parents have disowned him(at age 14) for no apparent reason.

Enough of the sob story.....
 
BonairII

BonairII

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Re: 80hp Johnson now BOGS at WOT!

I appreciate the link(I've already seen it), but it won't work for me. First...I'm not looking for WOT timing, I'm still having probs with the darn thing idling correctly. Second...I don't know what spark setting my motor calls for, Third....I don't have a timing light and have no idea how to use one.

What I'm trying to figure out is is whether my butterflies are opening at the proper time in relation to the timing advancing(or vice versa).

I'm going to fill up with fresh gas(maybe some rainwater somehow got into my gas when it rained the other night) and change plugs again...just to take them out of the equation.
 
relocyo

relocyo

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Re: 80hp Johnson now BOGS at WOT!

If you set the wot timing that also corrects idle timing, or at least thays what joe reeves says...
 
fireman57

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Re: 80hp Johnson now BOGS at WOT!

You can also run a clear fuel line from your fuel pump to the carbs and watch to see if you see air or water separating in it. If you just changed carbs from another engine they could be dirty too. If you want to check and see if both banks are getting fuel pull your plugs out and crank it over and watch for a mist of fuel coming out all the plug holes. If one doesn't have that you have a problem in that carb.
 
BonairII

BonairII

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Re: 80hp Johnson now BOGS at WOT!

I cleaned both carbs, so I doubt that both of them were dirty. I'm going up to work on boat today. I'm going to change plugs and I've got fresh gas.
I'm going to reset points again...I really have a feeling that that is the issue here. I find it really hard to believe that both carbs I have are dirty since NOTHING changed when I swapped them out.
I found this post by Joe Reeves, so hopefully this will help me. I can't seem to blow the pics up to see where the timing marks are(the pics hide behind the ads when I magnify the page:mad: ), but hopefully I can manage.
 
fireman57

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Re: 80hp Johnson now BOGS at WOT!

bottom left is the close button for the ad
 
BonairII

BonairII

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Re: 80hp Johnson now BOGS at WOT!

Changed plugs and distributor cap today... No change. I cleaned out high speed jets and found a piece of dirt jammed in one of them. It didn't change anything regarding the sneezing though.
 
fireman57

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Re: 80hp Johnson now BOGS at WOT!

The sneeze would be in one of your low speed or idle jets. It's funny you said in the post before last "I cleaned both carbs, so I doubt that both of them were dirty." and yet you found junk in a high speed jet. Sounds like you have crap in your gas tank. Get an inline filter and install it after the primer bulb. That will keep junk out. Did you ever change fuel? If you have water in it it will sneeze and die all day long. Look at the cheap fixes first.
 
BonairII

BonairII

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Re: 80hp Johnson now BOGS at WOT!

I sprayed carb cleaner thru the hig speed jets and fluid sprayed right thru. When I held jet up to the light I could see thru it, but I did see a piece of dirt wedged in it.

Update: misted left carb heavily while motor was idling/sneezing and sneeze seems to be gone. carb is gonna have to come off again I guess. No idea if it's dirty of leaking air at a gasket
 
fireman57

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Re: 80hp Johnson now BOGS at WOT!

Sounds like you found your problem. Make sure your low speed/idle jet is clear
 
BonairII

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Re: 80hp Johnson now BOGS at WOT!

Success! Pulled the low speed needle again and sprayed the heck out of the hole. Made some adjustments to the needle and voila! It's not perfect, but it'll suffice for now.

Took it for a test run and she roared to life and put me on plane in hurry! Topped out at 33mph. Not sure if that is all the speed it's capable of or not. Gonna do more tweaking tomorrow.
I have an extra prop... I may try it out. Seems to be a Lower pitch so maybe I'll get some additional speed. Don't have a tach, so it won't be an exact science. Motor is on first pin, may try to lower it a notch toward the transom.

After all the parts swapping I did, at least I know that the carb, fuel pump, coil, and distribution cap from my parts motor are good.
 
fireman57

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Re: 80hp Johnson now BOGS at WOT!

amazing how someone can clean a carb and there is always something in there. Glad you are running again. Enjoy what's left of the summer and stay around here and help others. Good luck and stay safe.
 
soundchaser

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Re: 80hp Johnson now BOGS at WOT!

That's because they don't remove the main needle valve body from the carb and clean in there.
 
BonairII

BonairII

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Re: 80hp Johnson now BOGS at WOT!

soundchaser said:
That's because they don't remove the main needle valve body from the carb and clean in there.
Click to expand...

Actually I DID clean in there. It was clear as a bell the other day, the speck of dirt was new and was in the carb that was ok. The left side carb was the one running lean.

I'm going to reinstall the 12 gallon bow tank tomorrow(currently using a portable tank) and am going to install a fuel filter, so I don't have anymore crud making it's way into the carbs.
 
fireman57

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Re: 80hp Johnson now BOGS at WOT!

It can still get crud from the air intake but it is most likely from the fuel tanks.
 
fireman57

fireman57

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Re: 80hp Johnson now BOGS at WOT!

Look at the 4th post down. did you ever pull the plugs and make sure that fuel came out of the holes? If the one carb was not getting fuel because of a clogged jet there would have been no fuel to the plug, hence, no mist.
 
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