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Cant get 4hp to stay running

J

jeckel7234

Member
Hi all, Ive got a 1999 4hp J4REEA, thats been sitting for a few years. I've replaced the water pump impeller and rebuilt the carb. Now I can get it to start but only at full throttle and it will sometime run okay at idle but then will bog down and die after 15-30 seconds. If i keep throttling it up I can get it to run for maybe 1-2 minutes before it bogs down and dies. I've adjusted the low speed needle to where I feel it runs the best but I still have the previous mentioned issues.

So I went inside to the high speed needle (feeling this is my issue) and there doesnt seem to be any real adjusting that, either in snug or its loose. Can anyone please give me ideas on what to check next. The motor feels like it has good compression, if anyone know the exact spec i can check that to make sure. Ill also link pictures of how I have the float set

https://goo.gl/photos/MC5wqq3KtyFyEn4X7

https://goo.gl/photos/FcgmeotSLACAEb8k7



Thanks,
Drew
 
The float looks good. Is the fuel fresh? Disconnect the fuel line from the carb and see if you get good flow out of the tank into a jar and look in the bottom of the jar for water. All it takes is a little water in the tank to make you scratch your head. Are you adjusting the carb with the motor in a barrel of water half way up the leg? I`m thinking it is slugging water or the fuel filter needs replaced. That has the onboard tank correct?
 
http://www.marineengine.com/parts/j...4REEA&manufacturer=Johnson&section=Carburetor


The link above is to a diagram of the carb. The motor has an internal tank and I have an external tank hooked up to the engine, both have good fuel flow all the way to the carb. And I have cleaned the mesh strainer that's in the fuel pump. The motor sat for years, without being touched, I did drain out the fuel, but its possible there is water still in either tank, ill dump some into a jar when I get home and check. I have the motor clamped to a barrell with water slightly past the gear case, I don't think I have it half way up the leg but when it is running there is a steady flow of water coming out the back, am I wrong in thinking that was sufficient? And when you say slugging water, there is some oil that's in the water, I didn't take that as a big deal being whats typically in lake water, and my thought of it just running up the shaft, running against the block and being spit out the back, am I wrong for making that assumption too? Thanks for all the suggestions Ill keep this up to date on my status, anymore ideas if my assumptions were correct?
 
slugging water on those small motors means ther is water in the float bowl fuel lines and tank and you will have issues until all the water is out. Have you tried pumping the primer bulb while running? If you know its getting fuel starts good and just stops it is very likely a drop of water is all it takes. water will look kinna like a air bubble in the bottom of the jar. When adjust the slow needle you need the water half way up the leg to create the backpressure you need to properly adjust it when the engine is up to temp and in forward gear. Once on the water you can fine tune it after running WOT for a bit. Allways adjust it a tad rich to protect the motor if you do alot of trolling.
 
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Last night, i dumped out the old water and filled the bucket with new water half way up the shaft, I then dumped the fuel into a clear container and their didnt appear to be any moisture in the fuel. I did how ever notice the outside of one of the fuel lines starting to deteriorate around where the clamp sits. So just to be safe I went and replaced the fuel lines, and then decided to give the carb another look over just incase any of the debri got up in the carb.

I ended up finding the brand new packing washer (#8 on the diagram), that i installed was deformed and broken up into alot of tiny pieces. I cleaned that out and went to replace that but obviously as i tighten the nut (#7) it forces the washer to deform. What is the standard procedure for tightening this? DO you just snug it up? And for reference #21 on the diagram is a plastic washer & #8 the packing washer is made out of some kind of leather or something similar

http://www.marineengine.com/parts/j...4REEA&manufacturer=Johnson&section=Carburetor
 
I put in the nylon washer first and then install two packing washers and then snug it down so it is difficult to turn the needle without the knob on it.
 
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