Super weird no start problem- please read

[LargemouthBass21]

Ok so I’m having a weird problem with my 3hp 1964 evinrude... it’s got spark now

(Cleaned and adjusted points), new head gasket, and carb cleaned and rebuild but I’m having an issue. If I dump fuel in the carb it starts up and revs then dies. If I try and start it normally it won’t run for more than a 1 second sputter. Sounds like fuel starvation right? WRONG... if I crack open the bowl drain screw fuel trickles out very slowly. I took the carb back off

And looked at the float, needle and seat, the spacer between the carb body and the seat makes the clearance so the float won’t open enough if that makes sense (I couldn’t blow air through with the carb flipped either way. I then removed the seat spacer/gasket (made of plastic) and reassembled. Then I could kind ofblow air through when it’s right side up but when I flip it over it’s blocked. Perfect... still won’t run though, jets are all perfectly clean, passageways have been cleaned. Super confused. Seems like it has to be a starvation issue as if I let it sit a long time I could get a slightly longer sputter out of it. The super weird part is that even though with the spacer in place I couldn’t blow through the inlet with the carb flipped either way, it still somehow got a little fuel in the bowl. When I removed the spacer it let’s a lot more fuel out of the drain bowl, basically as much as if I just let the open fuel line empty. Sooo what could be my problem? Tank is clean I have good fuel flow all the way to the carb (filter is NOT plugged), spark is good, and I don’t think it’s a compression issue because I’ve gotten it to run a decent amount of time before. It starts right up when I dump fuel in the throat. Very very weird I don’t understand

 

[Crosbyman]

if you put your hand on the carb can you feel air being sucked in when pull the starter cord ….

if gas does not get sucked in it won't burn any

is this a new issue a new motor to you …. did it ever work properly what changes were made and why

did you clean the low speed chamber on top
try openning up the ls screw a bit and confirm the hs jet is clean ..
the low speed circuit feeds up by a side channel and the hole in the gasket must line up do you have the correct gasket
could you gasket be snagging the float shut
does the choke plate close…

is the silencer full of bugs ?? did you clean it out ?

 

[flyingscott]

Take the screen out of the tank and look at it. If your screen is plugged it will cause your problems. If you crack the screw on the float bowl then fuel should pour out not dribble.

 

[tomhath]

And looked at the float, needle and seat, the spacer between the carb body and the seat makes the clearance so the float won’t open enough if that makes sense (I couldn’t blow air through with the carb flipped either way. I then removed the seat spacer/gasket (made of plastic) and reassembled. Then I could kind of blow air through when it’s right side up but when I flip it over it’s blocked. Perfect...

Not prefect, you should be able to blow easily through it when right side up. Sounds like the float isn't opening all the way or is set way too low.

 

[LargemouthBass21]

Take the screen out of the tank and look at it. If your screen is plugged it will cause your problems. If you crack the screw on the float bowl then fuel should pour out not dribble.

The fuel flows out of the line really fast, I think it’s fine there. Filter isn’t plugged. Fuel doesn’t get to the carb if I have the seat spacer in there though

 

[racerone]

What is a " seat spacer "----picture ?

 

[LargemouthBass21]

if you put your hand on the carb can you feel air being sucked in when pull the starter cord ….

if gas does not get sucked in it won't burn any

is this a new issue a new motor to you …. did it ever work properly what changes were made and why

did you clean the low speed chamber on top
try openning up the ls screw a bit and confirm the hs jet is clean ..
the low speed circuit feeds up by a side channel and the hole in the gasket must line up do you have the correct gasket
could you gasket be snagging the float shut
does the choke plate close…

is the silencer full of bugs ?? did you clean it out ?

Whole carb has been cleaned. It doesn’t even have a silencer at all. Gasket is lined up but when I tighten the bolts on the bowl, the bowl and carb body have a gap and I have to force them together until it’s tight. (I’m positive that’s just the jet going inside the hole in the bottom of the bowl like it’s supposed to because I took the float out and it’s doing the same thing. When it’s tightened, I can’t blow through the fuel inlet either way (float doesn’t drop enough to let it in) I removed the seat spacer to give it more travel and then I could actually blow through it slightly when the carb is right side up. When I open the bottom nut, fuel flows through much much faster but engine still won’t start. Plugs had a tiny bit of oil on them but weren’t completely damp. Poured gas into the carb throat and it fired up again... think it could be low compression? When I pour in gas it runs good so hard to believe that could be the issue. Reed valves are still flexible too

 

[LargemouthBass21]

What is a " seat spacer "----picture ?

If I take that o ring out I can kind of blow through but if it’s in I can’t either way the carb is flipped. Float is adjusted like it’s supposed to be also (pretty much level with carb body. If the spacer is in there, the float can move down but not enough to fill it up with fuel. If it’s out it gets a lot more fuel but still doesn’t run. Everybody uses that spacer though in their rebuilds. What am I doing wrong I ordered the kit straight from evinrude too it’s legit OMC parts

 

[racerone]

You need to go through the carburetor again.------Something is wrong.---You did remove / clean the high speed jet ( orifice ) to make sure it is clean.-----Or bring the carburetor over I can sort it out !

 

[LargemouthBass21]

You need to go through the carburetor again.------Something is wrong.---You did remove / clean the high speed jet ( orifice ) to make sure it is clean.-----Or bring the carburetor over I can sort it out !

I checked my compression today, 80lbs in both like dead even 80 both times. Is that enough? EDIT: the gauge is acting screwy and the needle is staying at 10 lbs when I let the air out, can I assume then my compression is 70lbs?

 

[LargemouthBass21]

You need to go through the carburetor again.------Something is wrong.---You did remove / clean the high speed jet ( orifice ) to make sure it is clean.-----Or bring the carburetor over I can sort it out !

Yes I did clean the high speed jet I can see right through it. Could you help me figure out why when I put it together the float won’t move with the spacer installed? I just don’t understand.

 

[racerone]

Is the float upside down ?----Is it the correct float.------I have a bunch of these 3 HP motors.----Picked up 2 last week.-----Your motor should be easy to figure out !!!-------Perhaps time to look at some videos to spot the mistake being made here.

 

[LargemouthBass21]

Is the float upside down ?----Is it the correct float.------I have a bunch of these 3 HP motors.----Picked up 2 last week.-----Your motor should be easy to figure out !!!-------Perhaps time to look at some videos to spot the mistake being made here.

That’s the issue, I’ve tried everything I can think of. Float looks the same way as it does in diagrams. I’ll take a picture tonight and post it. I’ve watched a TON of videos that’s why I don’t see what could be wrong

 

[Grub54891]

Does it have the correct Needle and seat?

 

[robert graham]

The small metal tab on the float can be bent slightly to adjust the needle hight so fuel level and flow can be adjusted....these carbs are super simple. Is the needle sticking in the cut off valve?....

 

[LargemouthBass21]

The small metal tab on the float can be bent slightly to adjust the needle hight so fuel level and flow can be adjusted....these carbs are super simple. Is the needle sticking in the cut off valve?....

I understand that but the issue is I have it adjusted how it’s supposed to be (about even with carb body) and it still doesn’t flow fuel. I’ll play with the float and see what happens

 

[LargemouthBass21]

Does it have the correct Needle and seat?

It has the one off of evinrudes website

 

[oldboat1]

Replacement needles, seats and plastic washers typically come with a small wire clip that clips over a machined slot in the needle, with the larger end hooked over the float arm. The tip of these needles is either black or red neoprene (can stick in the seat -- which is handled by the wire clip.)

The washer goes all the way down to the head of the seat, and the fit can be tight -- needs to be rotated/screwed over the threads down to the point where it fits flush. Not much change in these for many years. Use the whole assembly that came with the oem kit (needle, seat, and wire clip).

 

[LargemouthBass21]

Replacement needles, seats and plastic washers typically come with a small wire clip that clips over a machined slot in the needle, with the larger end hooked over the float arm. The tip of these needles is either black or red neoprene (can stick in the seat -- which is handled by the wire clip.)

The washer goes all the way down to the head of the seat, and the fit can be tight -- needs to be rotated/screwed over the threads down to the point where it fits flush. Not much change in these for many years. Use the whole assembly that came with the oem kit (needle, seat, and wire clip).

Sorry I’m slow, what needs to sit flush

 

[racerone]

Follow these steps word for word.---Turn fuel off.-----Remove carburetor ------Remove carburetor bowl.-------Install carburetor.---Motor in normal running position------Hold float up.------Turn fuel on.------Lower float and see fuel pouring through the float valve.------Raise float and see fuel flow stops.-----Report on this test.