1971 Evinrude 40 hp SkiTwin carb float valve

This topic has 8 replies, 6 voices, and was last updated 2 years, 8 months ago by fleetwin.

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July 28, 2021 at 2:44 pm #243800
MarkD
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US Member - 2 Years
I have had problems with the carburetor flooding, as gas poured out after pumping the fuel line indicating the float valve wasn’t closing. I thought I had fixed it (with new float and reuse of old needle) but then after a few minutes on a lake and a jolt from the boat gas started pouring out again. I have a new float and new float valve and seat that was made (this time) by OMC. The new float valve and seat came with a very small spring that I didn’t have in the old one. Should I use it and if so how does it go? The picture shows what it looks like.

thanks,

Mark
- This topic was modified 2 years, 8 months ago by Mumbles.
July 28, 2021 at 3:03 pm #243803
frankr
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The round end of the spring snaps into the groove on the needle, The straight section hooks over the float arm, The deal is, when the float drops it drags the needle down off the seat. All this because they had problems with the soft tipped needles sticking in the seat hole.
July 28, 2021 at 3:15 pm #243804
crosbyman
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Canada Member - 2 Years
depending on the needle/seat part some needle seats have longer threads some shorter ! make certain the needle tip sits properly when the float is level to the carb body edge . at least do a blow test on the carb to ensure proper shut-off.

upside down NO air should flow in the carb if you blow in the inlet nipple

Joining AOMCI has priviledges 🙂
- This reply was modified 2 years, 8 months ago by crosbyman.
July 29, 2021 at 9:08 am #243849
fleetwin
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US Member - 2 Years
Are you using an OEM piece for the float valve? Perhaps there is something interfering with float movement, swelled bowl gasket or something like that….
July 29, 2021 at 12:32 pm #243871
MarkD
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When I rebuilt the carb I used a non OMC float valve. The new one I have is OMC, with a metal seat and metal tipped needle. I could only figure out one way to get the spring to fit, and you can see it below hooked on the needle. The small end snaps on the groove in the needle, and then the large loop fits through the hole in the float. Does this look right?
July 29, 2021 at 3:26 pm #243893
David Bartlett
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Mark,

The spring doesn’t go through the float bracket. It just slips over it from the side.

David Bartlett
Pine Tree Boating Club Chapter

"I don't fully understand everything I know!"
July 29, 2021 at 4:09 pm #243899
outbdnut2
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Do you have the float level set correctly so it can shut off? I use Crosbyman’s blow test, in his post above, all the time on carbs to be sure the valve shuts off. That test will also fail to shut off if the float is rubbing on something that restricts its movement after the bowl is screwed on. If it passes the blow test and the float is good (not sinking), the carb shouldn’t leak gas.
Dave
July 30, 2021 at 12:48 pm #243971
fleetwin
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US Member - 2 Years
David Bartlett wrote:

Mark,

The spring doesn’t go through the float bracket. It just slips over it from the side.

Good eye, I missed that totally…
July 30, 2021 at 12:49 pm #243972
fleetwin
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US Member - 2 Years
Perhaps that cork float is fluid soaked causing this issue, or was it new with the kit? Some of the older OMC carb kits still have the cork floats….
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