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Fuel mixture and holding in choke

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amattpitre

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"I've had a problem with m

"I've had a problem with my 1988 88hp johnson loosing power. If I hold in the choke, it will run ok. I cleaned the carbs and the engine ran ok for a couple hundred yards then the same thing happened. I recently accidentaly ran the boat through one 6 gallon tank of gas with half the amount of oil.( i added 3 gallons without adding more oil...oops), but the engine ran w/o holding in the choke. I was excited and thought that i fixed it by cleaning the carbs. when i switched over to the correct fuel oil mix in new tank. I had to hold choke in. So i guess my question is, is there something wrong with the carbs, or how safe is it to run with that little oil mix in the gas? I was running it at 50:1."
 
"If pumping the fuel primer bu

"If pumping the fuel primer bulb (acting as a manual fuel pump) corrects the problem, either the fuel pump is faulty of a air/fuel leak exists at some point between the fuel pump and the fuel supply.

Does the primer bulb have a tendency to go flat when you have the choke out? If so, a fuel restriction exists.

If the above is okay, you're overlooking something within the carburetors."
 
do you know what's the min

do you know what's the minimal amount of oil/gas mix i can safely run in this engine? I checked the bulb and lines. all air tight.
 
"Allen, that "goof" me

"Allen, that "goof" meant you ran at about 75:1 for a bit. That by no means should have caused a great deal of problems. The newest variable rate oil systems will vary between 100:1 and 50:1 with a conventional 2 stroke motor - so you should be fine.

I have a bulleten around somewhere from OMC on the subject. They did market a number of motors in the later 80's that initially recommended running at 100:1. They later revised that and stated that they should be run at 50:1 unless a number of conditions were met.

In any event, you probably did not do any damage to the motor - but do continue to mix at 50:1 in the future.."
 
"just to clarify. if I ran les

"just to clarify. if I ran less oil than 16 oz in 6 gallons, say 8oz oil 6 gallons, would that increase or decrease the ratio? I found the engine ran better with less oil. according to mixing instructions on the oil, the higher the ratio, the more oil you add. so if I run a 100:1 I would double the amount of oil correct?"
 
I found the "needle" i

I found the "needle" in the bowl was getting hung up in the "seat". Is there a remedy for this or what do I need to replace?

thanks alot for the help.
 
as far as oil goes i bought a

as far as oil goes i bought a measuring container at walmart on clearance about this time of year for $.50.........or 1 pint to 6 gals-----50:1

on your needle is there a rubber top on it? does it have a indention (ring) around it about in the middle were it seats? if so sometimes you can take a fine piece of sand paper and twist the rubber back and forth to rid the indention or replace it.
 
""just to clarify. if I ra

""just to clarify. if I ran less oil than 16 oz in 6 gallons, say 8oz oil 6 gallons, would that increase or decrease the ratio? I found the engine ran better with less oil. according to mixing instructions on the oil, the higher the ratio, the more oil you add. so if I run a 100:1 I would double the amount of oil correct?"

no... that is half of the amount of oil, think about it like this 1:1 means 1 Oz of gas per 1 Oz of oil, example 50:1 means 50 Oz of gas per 1 Oz of oil another example 1 Gal(128Oz)of gas per 4 Oz of oil will give a ratio of 32:1,
Your problem sounds to me like if your motor is running rich(you stated that it ran better with less oil(~75:1) remember less oil means a lean mixure, maybe a re-jet will do.
uhoh.gif
"
 
Thank you guys for all your he

Thank you guys for all your help. I bought a carb kit from this site and wow it was here the next day. david r suggestion about the needle was correct. it did have a "ring" around the rubber tip. needless to say i put the kit in and she ran great no problems. i sold the boat and wont be getting another. but thanks for all the help. and yes i disclosed all the problems i had and passed on your site to the new owner.....
 
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