64 johnson 9.5

[kockxj]

I have a 64 johnson 9.5 I bought last year with a broken pull cord fixed that seemed to run ok but never great and now its gotten worse I cleaned the carb and read joe reeves thread about setting the valve but it still wont idle and it starts clunking or coughing then dies unless I hold the throttle at the start position and let it just rev. Any Ideas?

 

[bernd64]

Re: 64 johnson 9.5

the a very smal bypasses in the carb and you mostlikly still have some buldup in them it is not so eazy to clean a crab very good.

 

[Daviet]

Re: 64 johnson 9.5

Did you remove the little core plug on top of the carb and clean the passages in there?

 

[kockxj]

Re: 64 johnson 9.5

By core plug which one do you mean?

 

[Daviet]

Re: 64 johnson 9.5

Page #2, item #42
http://www.marineengine.com/parts/v...ntage-evinrude-johnson/278540/27854000001.htm

 

[bernd64]

Re: 64 johnson 9.5

the is a smal round plug on the top of the carb and one more in the foat boal

 

[kockxj]

Re: 64 johnson 9.5

No I did not remove that, but how would I remove it?

 

[cajuncook1]

Re: 64 johnson 9.5

Couple of things to do before you tare into the carburetor again. ( Previous suggestion made by the previous posters are very good suggestions and should be followed up with)



The 9.5hp Evinrude/Johnson motors were known to have exhaust leak issues that would make a motor run poorly. Also, vibration dampeners were not added to the motor until late 1966 and definitely in 1967. So, the 1964 to 1966 motors idled a bit rough due to the excessive vibration, so the dampeners and slight carburetor adjustments improved idling from 1967 an on.


Suggestions:

- If you are running this motor in a barrel, then put a fan next to it so the fan can blow the exhaust gases away from the motor. The 9.5hp motor was built compact and sits low in the barrel, so it has a tendency to inhale its own fumes and idle and run very poorly. (Usually not a issue on the open water and while running and moving along.)

- If the fan does not help much, then remove the motor cover. If the performance improves then you have a exhaust leak issue.

There are four known areas that can leak exhaust gases inside the motor cover and smother the motor. That is why you have rev up the motor to run rich to stay running.


Leak 1 = Is in the first attachment picture and is part # 87 SEAL,Exhaust housing. It torn, cracked, miss shaped over the years or trash collected in between the side and exhaust housing then exhaust gases can accumulate up near the motor.

Leak 2 = Is in the first attachment picture and is part # 43 HOSE,Exhaust. If cracked, torn or loosely clamped then exhaust gases can escape and accumulate in the motor cover and smother the motor.

Leak 3 = Is in the first attachment picture and is part #78 BOOT,Shift rod. If torn, cracked or missing then exhaust gases can escape and accumulate in the motor cover and smother the motor.

Leak 4 = Is in the second attachment picture and is parts #6 SEAL,Impeller housing and part #7 WASHER,Seal. If missing then exhaust gases can escape and accumulate in the motor cover and smother the motor.


Hope these suggestions are able to help you to remedy your situation.

 

[Bradley73]

Re: 64 johnson 9.5

Interesting section, as I have been struggling with my '64 9.5 Evin rude in much the same way as original post. Basically, the longer it runs, the worse it runs, but sometimes even starts out shaky. Just had the points, coil, spark plugs changed with the carburetor rebuilt with very minor improvements. The boat will sometimes take off and go 19mph est., slowing to barely being able to maintain a plane at around 13 mph. Sometimes, and I emphasize sometimes, if the motor cover is off while running it seems to run better. After running the boat for 2 hours straight, it was revving up, then back down, ect. I shut it off for about 5 minutes and after restarting the motor it launched straight to 19mph. Today, it didn't want to start and never ran over 14mph and running rough (vibrating and sounding like the prop was cavitating, which it was not). Does this fit the profile of a motor with an exhaust problem? Thanks in advance!!