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1973 Johnson 9.5 Carb Question?

6

6tring

Contributing Member
I plan to rebuild the carb on a 1973 Johnson 9.5 hp. Manual instructions shows the removal of the fixed jet. Is it advisable to remove the fixed jet during rebuild? Why I cast the question is that it appears one would have to use the orfice removing tool {Part 0317002}which comes with a price tag of $40.00. If it is recomended that the jet be removed for a proper cleaning I will put out the cash for the tool but other wise would like to purpose the cash for other necessary parts. Thanks for any input on the matter.....Don
 
A 3 /16" diameter screwdriver may take it out.-----Very little goes wrong with carburetors.----Why are you working on it?.----What other trouble shooting has been done on this motor ?
 
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racerone said:
A 3 /16" diameter screwdriver may take it out.-----Very little goes wrong with carburetors.----Why are you working on it?.----What other trouble shooting has been done on this motor ?
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Recently bought this motor. Previous owner had this motor in protected storage for 40 years. Never serviced, all origional parts. I figure things in the carb could be tacky. The throttle linkage was stiff at first and had to be slowly moved several times to free up. overall the motor is very clean and only seen freshwarer use in its early years. The paint is not even worn from the prop. I will be replaceing componets. Head gasket, thermo,plugs, impellor. Fuel lines are stiff at carb and pump. Have not checked spark. Will inspect the ignition componets under the flywheel. Mounts are good motor sits tight in its cradle. 80# compression in each cylinder. Sprayed stabill engine fogger in each cylinder before compression test to lube cylinder wall and rings. Want to be sure that this engine will be reliable as much as possible before going out on the lakes. Any other suggestion are welcome. "HAPPY NEW YEAR "</p>
 
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I will replace coils on your advice. Close inspection of points, clean or replace which ever called for.No question on impellor and carb, Will have to go over and clean every moveable part due to dry stiff lube and regrease.
 
Every coil on 1973 magnetos like that should be or has been replaced.----If it sat for 40 years they will have cracked as a result of aging.
 
racerone said:
Every coil on 1973 magnetos like that should be or has been replaced.----If it sat for 40 years they will have cracked as a result of aging.
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I can understand that. If I were to sit around for 40 years I would surley be aged and cracked
 
The early coils are covered with an inferior material. Please send photo of what coils are in there. Many replacement coils are just as bad. The mint green colored ones with the hard plastic coating often crack quite soon. They crack often in a safe area, but if they happen to crack on the bottom, then they eventually arc down to the stator plate. I like the softer composition coils, they are normally a dark maroon color. They last a long long time.
The jet can be removed CAREFULLY, with a properly ground screwdriver. The slot is wide on the jet, so you have to create a straight sided slotted end with the proper fit into the jet. If you force it and strip it out your "screwed". You can often clean it out right in place with a welding tip cleaner and CRC Throttle Body Cleaner. This is a very powerful cleaner, keep it off paint, and hands. Depends on what you find when you remove carb top. If it was stored completely dry, you might be "golden". It sounds like a mint gem of a motor. Take the prop off and remove the fishing line too. Also, new impellers now are a synthetic composition, they are not pure latex rubber. Please send photo of what you find upon removal of the original impeller. You may be surprised. In my tackle box, I keep a used OEM impeller for a 5.5/6 hp. It's 50 years old and still beautiful. Ha! Sounds like my wife!
 
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Make sure you get item number 17 (p/n 312909) as it doesn't come with the kit. It is probly brittle and will break removing it. Mine did. Dealer gave me that tip. Tons of dirt/grime behind that plug.
 
I have pics of the coils and overall motor. Cannot get them to post to the form. Frustrated! Anyways the coils are green in color with the letter M. The steel laminations are green. They appear to look good with no obvious cracking. Point gap is a bit tight with small heat/burn mark on contacts. I can send them via personal email. PM me for address.
 
Ok. Gots pics to work. Found that I had to down size.. Do these coils appear to be origional?
 

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Thanks fellows, I have to say I was pleasantly surprised at the pristine condition when I lifted off the flywheel. I will clean the points and impeller and see where it goes from their.
 
I have NEVER EVER seen screwdriver work like that. Ground wires are just the way that OMC installs them. Look closely at the picture. Our OP can tell if the flywheel has ever been off, if he studied the flywheel nut and the puller holes before he went to work. This is a real gem....WOW! These are original coils from OMC and they like to form hairline cracks. Is that a crack starting on one coil?
 

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OP chiming in. I myself question if the flywheel was ever removed. I had to clear a slight thread burr at the entrance of one of the puller holes to start the 1/4 20 puller screw. Do you think I opened a Johnson time capsule? I looked closely at the coils. I did not see any indication of cracking or crashing. This is about as far as as I will be going with the project for now till spring.
 
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First, Racer....the phillips screws show no sign of ever being removed. I always see, even the very best repair shops will put a mark in the screws, most often the slotted too. I am stupidly careful to never mark a screw, so I take note of what type of ape has worked on the motor before me. As I work on these I have just one phillips that I use that fits these screws perfectly, no one else uses my tools, ever. This looks like a "time capsule" 9.5 to me. OP, you are probably right, it has never had a puller installed before. I think that in 1973, this style coil was just beginning to be introduced. They can crack too, but not as severe as the older style with the very common coating which becomes brittle and shrinks, opening huge cracks and falling apart. I have a large box of them. When I was trained at OMC, the ground wires were to be installed in this position to help stop them from spinning as the slotted screw is tightened. RARELY do I see a previous repair set up with the ground wire positioned as shown here. The guy that assembled this stator was certainly a real pro.
 
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