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  #1   IP: 192.182.133.60
Old 07-10-2019, 02:02 PM
infy infy is offline
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A little choke needed to start and run?

I need about 20% choke to start and run the engine. Even after completely warmed up. If the engine is hot (~180*) and I kill the choke the engine will stall. At nearly any throttle. So some choke is always necessary.

Thoughts?
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  #2   IP: 137.200.0.112
Old 07-10-2019, 03:00 PM
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Your carb is clogged or otherwise running very lean.
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  #3   IP: 107.0.117.195
Old 07-10-2019, 03:14 PM
infy infy is offline
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Quote:
Originally Posted by joe_db View Post
Your carb is clogged or otherwise running very lean.
Thanks. I thought that it could be an idle adjustment. Doesn't sound like it, eh?
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  #4   IP: 137.200.0.112
Old 07-10-2019, 03:52 PM
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Not if it happens at full throttle too.
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  #5   IP: 70.185.132.167
Old 07-10-2019, 06:24 PM
JOHN COOKSON JOHN COOKSON is online now
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Quote:
Originally Posted by infy View Post
Thanks. I thought that it could be an idle adjustment. Doesn't sound like it, eh?
Why not adjust the idle and find out? Gently seat the idle adjustment then back it out 1 1/4 to 1 1/2 turns. See what happens.
As noted the idle adjustment will not affect high speed operation.
Concur that the problem sounds like an air leak somewhere.

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  #6   IP: 74.107.30.140
Old 07-10-2019, 10:56 PM
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sastanley sastanley is offline
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I would pull the carb drain/main jet access plug and drain it into a clear container and see if you get some gunk come out with it. If you have a mechanical fuel pump, give it a few strokes to flush a few ounces of fuel into the container and see what you got..hopefully clean fuel with no hitchhikers.

You should need 100% choke to start a cold motor, but after a few minutes, zero choke for normal operation.

What fuel are you running? Corn laced (ethanol) or E-zero? How much fuel do you burn thru in a season? I do not like ethanol fuels sitting in these old carbs for extended periods..I have found them to leave yellow honey/gel like gunk in the innards if they sit. If you use your boat regularly, not as much of an issue.
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  #7   IP: 192.182.133.60
Old 07-11-2019, 06:47 PM
infy infy is offline
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Quote:
Originally Posted by sastanley View Post
You should need 100% choke to start a cold motor, but after a few minutes, zero choke for normal operation.
Funny you mention that.. It takes a bit of cranking to start it. I've never got it to start with 100% choke. Or 0% choke... 20%-40% seems to be the sweet spot. WOn't start with throttle up.. seems to like throttle all the way down. So you can crank it at 100% throttle and get nothing... turn throttle all the way down and it starts coming to life.

Kill the choke and engine stalls.

Does sound carb related.

Quote:
Originally Posted by sastanley View Post
What fuel are you running?
90 octane ethanol.

Quote:
Originally Posted by sastanley View Post
How much fuel do you burn thru in a season?
Haven't done a season yet. Just drained the gas tank and put new fuel in from the automotive gas station.

So I've checked the lines, put on a new fuel filter, and the fuel pump seems to be fine.
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