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1968 33hp motor carb troubles

"motor is a 1968 33hp Johnson.

"motor is a 1968 33hp Johnson. Trouble starter last year and I thought I had it fixed until today. There is a low speed needle and a High speed needle. The motor will crank and idle but will only run about half throttle when I try and open it up, if I adjust the high speed needle it will open up and run like a champ. When I idle back down it runs very rough or not at all until I re-adjust the high speed needle again and then it will idle, but then Im back to it not running correct at high speeds unless I adjust the high speed needle again. I installed a carb kit a couple of months ago but am just now getting it on the water. I have rebuilt this carb 3 or 4 times in the past 25 years with no trouble. This has me stumped as its very basic, the needle screws into an opening and you adjust it back out and go. I have done it a 100 times but never had this happen. Im wondering if the carb is just worn out. I have a spare motor that was low hours and Im thinking of yanking the carb off, rebuilding it and installing it on my motor unless someone can offer up a better suggestion. Thanks for any advice.
Ken"
 
"If you have proper compressio

"If you have proper compression and spark, either the carburetor is out of adjustment (see below) or you've overlooked something in the latest rebuild (it happens).

(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
Re: "If you have proper compressio

Bonjour, Je répare carburateurs E50 TLECE un moteur EVINRUDE de 50HP.
Quelle est la procédure pour régler la vis de commande de mélange (PN 335015). Le carburateur a un ralenti jet 31 ref (PN318823). Merci beaucoup pour votre aide.
 
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