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Johnson 115ph 1990

1

13ow3n

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Issue is the motor runs fine when I first put it in the water, runs great idle sucks but I adjust the throttle and I do ok. When i shut it off to fish awhile I csnt get it started again and when it does there is NO POWER. I'll point at the sky for 4 minutes before it slowly picks back up. Once it does it runs fine.

New carb rebuild, new fuel pump
P, new filter, compression test passes, but the sparks are a little oily, 50:1, I'm thinking... Reeds?
 
So next test is for maximum spark.-----Does spark jump a gap of 3/8" on each lead , yes or no.----Your compression values indicate a cheap gauge.----Or a motor that needs work.
 
KyBullet said:
When you try to start it back up what does it do? Are you sure your timing advance is falling back in correct position?
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It hits a couple times and sneezes.. or it will turn over and start for a second but doesn't sound like it's all there. How would someone check something like that? I noticed today that the plugs had a little oil on them. So I'm thinking the primer silonoid is leaking as it sets and floods it out? I don't know I unhooked the gas tank today and let it idle until it died... fished for about an hour and re primed it. Started right uo no issues. So think that could be it?
 
racerone said:
So next test is for maximum spark.-----Does spark jump a gap of 3/8" on each lead , yes or no.----Your compression values indicate a cheap gauge.----Or a motor that needs work.
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I got them gapped to .03 but looking at them today they had some oil on them... wet oil. So I cleaned em and made sure the Gap was right.. ish... and went out. Launched, no issues... fished after I disconnected the tank and let it idle everything out of the carbs and lines... waited about an hour, hooked it back up. No issues, maybe primer silonoid leaking while setting and flooding?
 
Remove head where lowest compression is.------Post picture of what you see in there.-----Head gasket is cheaper than the super reliable electric primer valve !!-----And it is easy to inspect / test the electric primer valve.-----With the motor stopped , remove one of the small hoses at the carburetor and see if fuel leaks out.
 
IS that where the reeds set? I'll look into it and see if that's something I can do. I know I can figure it out. I've pulled the flywheel and changed the rectifier myself and I have the manual. I'll get back with you for sure.
 
racerone said:
Remove head where lowest compression is.------Post picture of what you see in there.-----Head gasket is cheaper than the super reliable electric primer valve !!-----And it is easy to inspect / test the electric primer valve.-----With the motor stopped , remove one of the small hoses at the carburetor and see if fuel leaks out.
Click to expand...
I just looked it up, that seems pretty easy. I'm going to order new gaskets so when I pull it, I'll have them and I'll post a picture of what I see. I just watched a video and a guy said his messed up because it over heated. I think the guy I bought it from dry fired it for awhile maybe because the rectifier was FRIED and it is water cooled.
 
Many folks are not aware of the fact that reeds have to do with compression in the 4 separate crankcases on a motor like yours.----Compression in the cylinder starts when exhaust ports close.----Reeds are not in the picture when compression starts in the cylinder.----If fact at that time the reeds start to OPEN to let a fresh charge into the crankcase.
 
racerone said:
Many folks are not aware of the fact that reeds have to do with compression in the 4 separate crankcases on a motor like yours.----Compression in the cylinder starts when exhaust ports close.----Reeds are not in the picture when compression starts in the cylinder.----If fact at that time the reeds start to OPEN to let a fresh charge into the crankcase.
Click to expand...
So it would have to be rings right? You think 90 is too low?
 
Difficult for me to see , hear and feel your motor.-----Does spark jump a gap of 3/8" on all leads ?----Test run with another tank and hose ?---Test run with cowling off the motor?----In my opinion it should be easy to figure out what is wrong here!----Flywheel key checked ?
 
Good spark, have not tested on new tank but interesting you say that because I tried to put gas in it this weekend and it shot back out at me. Runs the same with cowling on and off, and flywheel key is good, I just changed the rectifier so I got a good look at it. I'm going to take it out today and I'll try and get a video of it doing it.
 
racerone said:
Difficult for me to see , hear and feel your motor.-----Does spark jump a gap of 3/8" on all leads ?----Test run with another tank and hose ?---Test run with cowling off the motor?----In my opinion it should be easy to figure out what is wrong here!----Flywheel key checked ?
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I say good spark but I don't have an online tester, can I just gap a plug to 3/8 and ground it and fire and see if it sparks?
 
Glue 2 pieces of wire on cardboard.-----A 3/8" gap between them.-----Put one end in a plug boot.----Clip the other end on the engine block.-----Or use a timing light one cylinder at a time, as a " poor man's scope " and see how spark behaves.
 
racerone said:
Glue 2 pieces of wire on cardboard.-----A 3/8" gap between them.-----Put one end in a plug boot.----Clip the other end on the engine block.-----Or use a timing light one cylinder at a time, as a " poor man's scope " and see how spark behaves.
Click to expand...
That sir, I can do
 
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