9.5 Evinrude stalling

Shefloats

Recruit
Joined
May 21, 2019
Messages
3
Hello to all. I am new to the forum and boating and I Ihave run into a problem. So for a little background on my boat the outboard is a 1965 and a half 9.5 sportwin Evinrude. I just did a carb rebuild new JC4 plugs new fuel pump fuel lines gas tank.
The the boat runs fine and starts up in about 4 puls. And I can go a long time at full throttle but after running it wide open throttle for about 30 min it wants to die and I have a hard time getting it started. I have to wait for ten plus min and then it runs good for a short time then dies again. Does this untill starting it is almost impossible shorter and shorter run times in-between. It's been 90 plus degrees outside when I first noticed this happening.
​​​​​​Any ideas
thank you in advance for your time
 

w2much

Lieutenant
Joined
Jun 22, 2005
Messages
1,276
When it stalls. Check your spark with a good spark tester you are checking to see that it jumps a 3/8" or so gap, not that you have spark.Check your spark plugs. Are they soaked wet with fuel or do they look a nice brown clean burn ? If your spark is good you likely have a fuel issue. Is the primer bulb hard or soft ? Is your fuel tank vented? Did you set the float height correctly.? Did you change out your needle and seat in the bowl ? Expanding fuel and increase pressure could be forcing fuel past your valve and flooding you. An improperly vented tank may cause a lack of fuel. Hot weather may play havoc on your coils causing weak spark. You sound savy. Try these checks, let us know how you make out. There are more and better members than I here. Good luck.
 

Shefloats

Recruit
Joined
May 21, 2019
Messages
3
Those are good ideas I worried about float hight because I have only rebuilt a carb once but it runs flawless untill dies. When I squeeze ball valve it's not firm but doesn't seem squishy either. If I squeeze it hard enough gas runs out vent on carb at least I believe it's a vent. Does that mean float is not seating valve correctly? Also I have a plastic tank how loose should cap be? Too tight and tank expands and pushes fuel past float correct?
when you say change out needle you mean needle that float pushes up to stop flow right?
Sorry for the dumb questions outboards are very new to me.
 

w2much

Lieutenant
Joined
Jun 22, 2005
Messages
1,276
No dumb questions found. You have 3 questions to which your answer is a "yes" . The actual cap of the tank should be tight and the vent screw open, if it has one. If a brand new tank in Ca. it may have a pressure diaphram in line, does it have one? iIf you squeeze the bulb and fuel comes from the carb you are on track to finding your issue.. Did you install the nylon gasket between the needle seat and carb body? You need to redo your carb work. Soak it in parts cleaner or ultra sonic cleaner. Your needle is not seating. Your float may not be floating to exert enough pressure on the needle to seat it properly. New float ?
 
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