1972 Johnson 9.5 carb issue

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Trinity

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My 1972 Johnson 9.5 is having issues. I can only get it to start if I pour gas straight into the carburetor and it will not stay on. I checked the lines and I know I am getting the gas to the carburetor but I noticed that no gas is coming out the small pipe inside the carburetor when I prime it. I took the carb off and tried to clean it with carb cleaner and still nothing. I guess my next step is to let it sit in carb cleaner over night just wanted to know if someone had a fix. I would be thankful for any help.
 
Trinity,

Going to need a couple of questions answered in order to help you.

**PM me your email address, I will send you a service specific for your motor.**

** Never use straight gas to start and run your motor. You need to use premix fuel with oil. 50:1 ratio fuel to oil mix. Any TWC-3 oil marine 2 cycle will do. The oil in the fuel mix is your motor's only source of lubrication.**

1.) Is this motor new to you and has it run well since you have had it?

2.) Does your motor have a good spark coming from both plug?? You need to check with spark gap checker that you can get a auto parts store...about $6.00 cost and great to have. The spark should jump a minimum of 1/4 inch and have good bluish color. If it can't do that, then you have a ignition problem.

3.) Make sure you have the connector closest to the priming bulb connect closest to the tank the other end to the motor. (Don't laugh we have all screwed up and put it the other way) There should be writing or an arrow point the direction the fuel should flow. Pump the bulb up until is nice and firm or close to. Look for leaking from motor connector, fuel pump, and carb. When you pump up the fuel bulb, you are introducing positive pressure into the fuel system. (Make sure you vent the tank with the vent cap)

(please make sure you have it in a barrel, tank or on the boat in water)

If you get your motor started and the motor goes to die, pump your primer bulb on your fuel line. If this improves running or keeps it running then you may have a bad fuel pump.

You will need a new carb kit. (part number = 382048)

Here is place that has an electronic diagram for your motor and you can purchase parts. You can also go to local Evinrude/Johnson dealer as well.

https://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1972&hp=9.5&model=9R72M


Well, let us know what you find and we can go from there!! I have 3 of those buggers :lol:
 
Thanks for your help cajuncook1. I was using fuel and oil from my gas tank straight to my carb to get it to fire, sorry I was not more specific.

1.) Is this motor new to you and has it run well since you have had it?

Answer- This motor had ran well for me before this. I even took her to a shop to get her tuned up and got hit in the pocket hard. That is why I am doing the work myself this time, it was running better before they touched it. They replace the water pump and rebuilt the carb.

2.) Does your motor have a good spark coming from both plug?? You need to check with spark gap checker that you can get a auto parts store...about $6.00 cost and great to have. The spark should jump a minimum of 1/4 inch and have good bluish color. If it can't do that, then you have a ignition problem.

Answer- I am going to stop and get one today. I will update you as soon as I check.

3.) Make sure you have the connector closest to the priming bulb connect closest to the tank the other end to the motor. (Don't laugh we have all screwed up and put it the other way) There should be writing or an arrow point the direction the fuel should flow. Pump the bulb up until is nice and firm or close to. Look for leaking from motor connector, fuel pump, and carb. When you pump up the fuel bulb, you are introducing positive pressure into the fuel system. (Make sure you vent the tank with the vent cap)

Answer- Trust me I am not going to laugh. This is my first motor and I have already made that mistake. I have had the arrow pointing the wrong way and loose connectors. I am learning as I go. I am getting a good connection. I have even disconnected my fuel lines inside the motor to make sure I didn’t have a clog in my fuel lines.
 
Check your email, the manual should be there!! Let me know if you did not get it.
 
When I spoke of a spark checker, this is what I was speaking of.


sparktesterpic.jpg
 
Take it back to the place that screwed up your carb and have them fix it.
 
If after you check to see if both cylinders have spark and your motor does not start, then make sure the person who worked on your motor did not switch the plug wires around. Meaning the top wire is on the bottom cylinder and the bottom spark plug wire is on the top cylinders. Usually one of the wires will be labelled with a metal clip labelled top. If the wires are crossed then the motor will not run. The motor's firing sequence is out of sequence. The motor will fire (produce spark) when there is no fuel or compression, so no combustion.

Here is a way to verify your wires, if they are not labelled. (Borrowed the picture from a fellow AOMCI member)

TopCyl.jpg



If it still does not start, then make sure your carburetor settings or correct. Here is some instructions from a very good mechanic.

Carb Needle Adjustments For Asorted Carb Variations by Joe Reeves

these adjustment are for the older engine. 1980 and earlier, and the current small hp ob's. not for fixed jet outboards.


(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently(turn in clockwise), then open 1-1/2 turns(turn out counter clockwise). Do not tighten or force the slow idle needle shut or it may damage the needle.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in (clockwise). Wait a few seconds (10 to 15 sec) for the engine to respond. As you turn the valve in(clockwise), the rpms will increase. Lower the rpms again (turn your throttle slightly slower) 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 (sounds like a mild backfire). At that point, back out(turn out counter clockwise) the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustment, 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.


Use the manual I sent you for reference. (It is an Evinrude manual, but there were only decal and very minute difference between the two brands....both made by OMC.
 
Ok, I am not sure what happen but she is running now! I took some time off and went on a cruise, hooked her up this morning and she is running. As soon as I primed it I could hear the gas going in the carb like it should and it started on the first pull. Got some good info and know-how so I guess all is well that ends well. I am going to try to take her out later to see how it is running on the boat. I will update, thanks for the help.
 
I have Johnson motor about same age. I have had this issue now & then. found it was the connectors on gas line. They look good & connected, but unplug & plug them back in, good to go. Seems to happen more on hot days. Think may be some kind of vapor lock?
 

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