59 Johnson CD-16 5.5 hp...NEED HELP

C

Crosbyman

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try a small quantity of fuel simply gravity fed to the carb.... just pump till the bulb is hard no more let gravity free flow the fuel in the carb the carb will shut of the in flow when full.. try the motor if ok fuel pump issue or pulse line filling with fuel


btw re: fuel on the brass screen issue ........if that fuel is coming from the pulse line... try changing to the alternate pulse channel by moving your rubber plug behind the carb plate... I never had fuel in the pulse line on my 5.5 but I used the epoxy method to block a pulse channel channel the right side one if I remember corectly (as in the film)

https://www.youtube.com/watch?v=FtG4M7ye1N8



if.... you do have fuel in the pulse line maybe you can try to route that pulse line more VERTICALLY before it reaches the pump itself this may allow any fuel to be drained/ sucked back in the crankcase before pooling on the low side of the hose

reorient the pump if you have to

good luck patience brings joy ....
 
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DaffyJeffy

DaffyJeffy

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Yesterday when I reconfigured the lines, I did not see any fuel in the pulse live - looked dry. I think I'm okay on that issue but when I install a new pump I'll check carefully again.

Thanks for your links, much appreciated.
 
DaffyJeffy

DaffyJeffy

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Sorry I haven't been updating my progress (got busy at work)...and thanks for asking Crosby.

So I finally tank tested with a gravity feed line directly to the carb. It ran much better, however there was gas leaking out somewhere...looked like bottom of the reed plate but it could have just been coming out of the nipple where I had the pulse line hooked up.

Here's the interesting part, when I pulled the reed plate off the vac cap fell out and there was definitely gas pooling in the bottom of the plate. I'm pretty confident I've found the problem. I'm going to fill the right hand channel with Scotchweld. Should I also put a vac cap in on the same side?
 
C

Crosbyman

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no need for a cap since you removed the check valve & only on cyl will be feeding pulses to the nipple


plug the right side channel as in the utube movie

I had no fuel issues with my 5.5 which I sold to a happy neighbor and he is still happy
 
DaffyJeffy

DaffyJeffy

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Ugh...not good. So I filled the right channel with 847, re-assembled and put'er in the test tank. Initially it ran okay then it surged and died. Ran it again, surged and died. Getting gas out of the side of the fuel pump breather just like before.

I pulled it apart, and sure enough, there is all sorts of gas in the bottom of the reed plate. So fuel is still traveling through the pulse line. Ugh...not sure what to do from here.

Something that I had considering doing is pulling the carburetor off the junker Johnson CD-25R 6 hp I have and putting it on this motor (this is a CD-16 5.5 hp) I don't really know if it's compatible. But could the problem even be the carburetor causing the reed plate to fill with gas? I'm so frustrated right now. :(
 
DaffyJeffy

DaffyJeffy

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Thank you. I think I'm going to try the other other carb on it. If that doesn't work I'll know it's not a carburetor issue. After that...whew, I don't know. I might end up stealing the power head off the 6 hp too if things keep going this way.

I'm going to be honest, I really regret this project. When I first checked the compression and it was bad, I should have bailed on the project and found a running motor to tinker with. Now I'm about $300 into this and I don't even want to know how many hours. I may have to just suck it up and pull the plug on this and part this motor out...I dunno.
 
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Crosbyman

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hours don,t count .. it is a hobby

you have real nice motor & when fixed 300$ will not be so big a mistake

if all else fails and patience/money runs out you could always revert back to a two line operation after finding a good tank
but do not part this beauty out ...even dead it is a nice show piece as is !!
 
C

Crosbyman

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reread your posts
Getting gas out of the side of the fuel pump breather just like before.....



Even with fuel in the pulse line why would that happen unless a diaphragm or inner part of the pump is faulty ???

to my knowledge that screen is just an open air vent to allow the inner diaphragm to expand and contract ..why would fuel reach the outside world ??

check crankcase purge valve as a reason to have excess fuel in the pulse line then try to figure out why the pump leaks....did you try another pump ??​
 
DaffyJeffy

DaffyJeffy

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Took the crankcase purge valve off...I can't see an issue with it (and why would so much gas not be burning off anyway?). It looks good so I put it back on.

I'm on my second fuel pump...gas coming out side port on both. It's just like gas is pooling in the bottom of the reed plate even when it's been running after a few minutes.

I have the 6 hp carb set up on it and I'm going to try that after work just out of curiosity, but in my mind, I cannot see how this is a carb issue. And if it's not a carb issue then what the heck is it?
 
C

Crosbyman

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I doubt a carb fix will do since this in behind the carb plate (all gaskets ok presumably)

recheck carb float and needle operation... redo a blow test on the carb to ensure needle is closing the inlet when holding the carb upside down (simulating a fuel bowl full of fuel)

adjust carb float lever with casing edge make sure float is not installed upside down itself !!!


going off line a few days.... myself
 
R

RCO

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Your problem lies with the fuel pump!!! With the diaphragm leaking the fuel is being pulled directly into the crankcase and pooling. It doesn't get atomized like when it comes through the carburetor. The motor cannot run correctly with one cylinder loaded with liquid fuel. The purge valve is meant to deal with a little residual unburned fuel, not a constant flow. Have you tried running the motor with the tank plumbed directly to the carb like was suggested several times? Those Chinese Briggs knockoff pumps work fine on a 4 stroke Briggs using the very slight crankcase pulse, but do not hold up to the increased pressure in a 2 stroke outboard. A factory B&S or a Mikuni snowmobile pump will work fine. 2 pumps, and both were leaking fuel from the vent. Take one apart for giggles, and you will see why you are having issues. There should not be even a drop of fuel in that area of the pump.
 
C

Crosbyman

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there you go ... use a small fuel container.. feed fuel DIRECTLY to the carb inlet . hold it above the carb

that will do away with any suspicions about the pump itself being out of the picture during the test .


good luck and report back with findings !!
 
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