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Have to prime carburator every time

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79century

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"well i got out on the water y

"well i got out on the water yesterday. my merc. 260 w/ 2 bbl rochester carb. would run pretty good, but with a bit of hesitation in acceleration. if i cut it off for more than a few minutes, i would have to pour a bit of gas in the carb to get it going. once running it was ok. it did cut out a few times at idle and didn't seem to run as strong as it used to. i rebuilt the carb. and changed to pertronic elect. ignition., so i expected it to run mch better than it did. also, when it was cold i only got a response from adjusting the idle screws in. when adjusting them out, it didn't make any difference in the idle. even when i screwed them nearly all the way out. but, when the boat was warmed up, i didn't get any response from screwing them in or out. so, i guess i didn't nail the carb. rebuild. it was my first one. i tried to be diligent. what do you think my problem is???"
 
Carb rebiuld is in order again

Carb rebiuld is in order again.!!

If you know how then do it if not have a proffesional do it. It will make all the difference in the world with a fresh rebiuld!!

There are a few things a first timer may miss so it may be best to have someone with more knowledge help.

Got any buddies with carb rebiuld experience?
 
"the carb rebuild has 0 hrs. o

"the carb rebuild has 0 hrs. on it! i am positive i left no gunk in it, or passages blocked. so, what adjustment ect. could be off to cause this problem?
come on kghost, go get that morning cup of coffee that makes you spit out all the knowledge a person can handle!"
 
"rebuilt the carb. and cha

"rebuilt the carb. and changed to pertronic elect. ignition."

Did you reset or check the engine timing?

How long did you soak the carb bowl and parts and what did you use? Compressed air is required to blow out the fine fuel circuits. Complete carb disassembly is a must for a thorough cleaning. Did you use a new accell. pump and float?

What carb adjustment specs. did you use? The kit sheet or the service manual? Kit sheets are notoriously wrong; use the manual.

"when it was cold i only got a response from adjusting the idle screws in."

Is the carb base gasket a thin one? A thicker gasket helps w/fuel atomization and idle mixture adjustment. I start w/the idle screw(s) in finger snug and backed out 1-1/4 turns. Adjust the mixture cold only if the idle is rough. Wait until the engine is at operating temp.
 
"thanks guy,
i set the timing

"thanks guy,
i set the timing to 8 deg. btdc.

i used a ultrasonic bath at my work (industrial plant) it uses a solution that's supposed to be safer yet more thorough than any solvent. it heats to 180deg. and does the ultrasonic motion thing. the machinists there have used it for carb rebuilds and swear its better than a carb solvent soak.
i blew it out w/ 80lb. compressed air very thoroughly.
the kit came with a new accel. pump. , needle and seat, i re-used the float, power piston, and primary & secondary jets, but all looked to be in good shape. the float is the black poly type.
i used the specs that came wth the kit. it is a merc./quicksilver kit. does that make any diff.?
i used the thin gasket, b/c i couldn't find the thicker one. i have some fuel rated gasket material. can i cut out several pieces of that to build up to 1/4"? i started out w/ the idle screws out 1.5 turns from fully closed. when i would screw each one in it would cause the engine to idle down. if i screwed t out it wouldn't effect it. but when warm it didn't idle down when screwd all the way in to closed."
 
I am familiar w/ultrasonic cle

I am familiar w/ultrasonic cleaning. It sounds like yours was cleaned well. No response from the mixture screws makes me think the fuel is not getting a chance to atomize sufficiently. A thicker gasket should do the trick.

"I have some fuel rated gasket material. can i cut out several pieces of that to build up to 1/4"?"

Give it a try.
 
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