Greetings all,
I have been enjoying the forum this past year. It has answered a lot of questions for me regarding my 1993 Carver Mariner with twin Crusader's 350XL's (small block)
I am in search of a site, youtube video etc. or if anyone here can provide information on adjusting the carbs on my Crusader's to make sure I have the proper fuel/air mix and idle.
Thank you, Michael S
Tierra Verde, FL.
Anyone have any info on adjusting carburetor (fuel air mixture) and idle. 1993 Crusader 350XL
- LUCKY RUBY
- Scurvy Dog

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- km1125
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Re: Anyone have any info on adjusting carburetor (fuel air mixture) and idle. 1993 Crusader 350XL
I'm surprised those aren't injected motors.
Do you know what kind of carbs are on it?
Doing a boat is no different than doing a car.
My process (on an unknown-to-me engine) is to first find out where the mixture adjustments are at. Turn them in one at a time and count how how many turns on each and then turn them back out to their original settings. They should be pretty close to the same. Record those numbers in case you have to go back to them. Run the engine, get it up to operating temp.
You could be confident that the timing is correct and the advance is working correct. If there is any doubt, check this first as it will have a huge impact on idle quality.
Set the engine to recommended idle. Double check to see if the idle is set 'in gear' or in neutral and set it appropriately.
If the mixture screws were very similar, you can start on either one, but if one was out more turns than the other, start with that one and start turning it in gradually, watching the RPMs and listening to the motor. When you start to see a drop in RPM or hear some missing, turn back out about 1/8 and go do the other mixture screw. Readjust idle as necessary and repeat the process.
Do you know what kind of carbs are on it?
Doing a boat is no different than doing a car.
My process (on an unknown-to-me engine) is to first find out where the mixture adjustments are at. Turn them in one at a time and count how how many turns on each and then turn them back out to their original settings. They should be pretty close to the same. Record those numbers in case you have to go back to them. Run the engine, get it up to operating temp.
You could be confident that the timing is correct and the advance is working correct. If there is any doubt, check this first as it will have a huge impact on idle quality.
Set the engine to recommended idle. Double check to see if the idle is set 'in gear' or in neutral and set it appropriately.
If the mixture screws were very similar, you can start on either one, but if one was out more turns than the other, start with that one and start turning it in gradually, watching the RPMs and listening to the motor. When you start to see a drop in RPM or hear some missing, turn back out about 1/8 and go do the other mixture screw. Readjust idle as necessary and repeat the process.
- LUCKY RUBY
- Scurvy Dog

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Re: Anyone have any info on adjusting carburetor (fuel air mixture) and idle. 1993 Crusader 350XL
@km1125 Unfortunately not FI I really appreciate the advice, thanks for taking the time.
- Tommyfmu
- Scurvy Dog

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Re: Anyone have any info on adjusting carburetor (fuel air mixture) and idle. 1993 Crusader 350XL
If it's a standard 650 cfm double pumper like Holley, Rochester, or Edelbrock, from a starting point both mixture screws should be 1 1/2 turns out. If adjustments have to be made due to running too lean or rich, then 1/4 turns at a time. Both sides need to be equally turned in or out. That's what my carb-rebuilder explained to me.