1984 Johnson 35hp

[GrandPrix74]

Hello All,

Been trying to get my 1984 Johnson 35 HP - J35ELCRR - back in shape. While inspecting and cleaning the carb I removed the low speed needle valve for cleaning. It was about 10 turns out. After I was done with basic carb cleaning I tilted the motor and let all the carb clearner and gas come out the carb. Reinstalled needle valve and come out about 1.5 turns. Started the motor and it fired up quickly, but at idle it skips, misses, spits. At high rpms the motor runs fairly well. Shortly after running for a while I started having trouble starting and keeping the motor running. The low speed needle valve was vibrating and backing it self out. Did some research and realized the needle should go in a retainer. Unless its stuck deep inside I'm missing the retainer. My question is can this missing retainer cause the air/fuel mixture to get out of whack even when its screwed in place?

 

[jimmbo]

Did you remove a retainer? New ones if needed come in OEM carb kits

 

[GrandPrix74]

No, unless I did I didn't realize it and that is possible. I've seen them in packs of 8 for a few bucks online. Hope to find locally.

 

[Faztbullet]

You cannot properly clean a carb still attached to a engine. Order a kit and remove it and replace all gaskets and clean it properly.

 

[GrandPrix74]

I did. I removed and the carb was clean. I cleaned anyway. I removed freeze plugs, cleaned with carb cleaner, then blew compressed air through it. Reassemble and my problems continued. I removed and rebuilt the fuel pump. Same problems. I'm on to the Electronic Primer now. My engine runs great when the electronic primer is in manual mode but sputters and dies when its in run mode.

 

[Faztbullet]

My engine runs great when the electronic primer is in manual mode but sputters and dies when its in run mode.

That because you still have a carb problem, the primer is feeding fuel bypassing the carb...

 

[GrandPrix74]

The carb didn't appear dirty when I initially took it off but I cleaned, and installed the rebuild kit. Sprayed lots of carb cleaner and compressed air through all openings.Removed and cleaned a second time with carb cleaner and air. I will soak it when I take it off this time.

 

[bonz_d]

Sounds to me as though the slow speed circuit is still dirty.

Don't recall this carb off hand but there should be a brass pick-up tube in the center sticking down into the bowl. Does this tube also have the small tube inside it? If so that small tube is the slow speed pick-up. It needs to be very clean or you will have problems. Ran a 18hp Evinrude that I had trouble with and had that carb apart 3 times before it was clean enough but once it was done it ran great.

 

[racerone]

Agreed you have issues in the carburetor.----Did you remove the threaded high speed jet found in the carburetor bowl, yes or no.

 

[F_R]

OR...you could have an air leak into the crankcase (bad seals). But make sure the carburetor is right before going there. The retainer should be visible as you look at the front of the carburetor. It is merely a friction device to keep the needle from spinning. There is also a seal, called a "bearing" that goes deep in the hole the needle threads into. For whatever it is worth, I have the same motor, and my slow speed needle runs considerably further open than the "normal" 1-1/2 turns out. But it runs perfect at whatever it takes.

 

[GrandPrix74]

Below are some pics of a very similar carb.

 

[GrandPrix74]

Agreed you have issues in the carburetor.----Did you remove the threaded high speed jet found in the carburetor bowl, yes or no.

No. I attempted but I need to get a special screwdriver.

I can blow threw the towel in the middle of the bowl and air flows threw the high speed orifice. I will order a replacement and tool to remove.

 

[GrandPrix74]

OR...you could have an air leak into the crankcase (bad seals). But make sure the carburetor is right before going there. The retainer should be visible as you look at the front of the carburetor. It is merely a friction device to keep the needle from spinning. There is also a seal, called a "bearing" that goes deep in the hole the needle threads into. For whatever it is worth, I have the same motor, and my slow speed needle runs considerably further open than the "normal" 1-1/2 turns out. But it runs perfect at whatever it takes.

F-R After putting the new retainer and plastic bearing from the rebuild kit on the needle I have to keep the low speed adjustment needle seated tightly.

I should also mention that after a lot of time trying various things I turned the primer to manual mode and the engine held an idle without sputtering/sneezing and accelerates very well. Another poster mentioned this is because I'm feeding fuel directly to crankcase. Would that be an indication the seals are OK and the problem is likely with the carb?

 

[racerone]

The primer unit is feeding fuel into the engine.---This fuel bypasses the carburetor .-----This clearly points to the fact that there are issues with your carburetor !!

 

[F_R]

Low speed needle seated tightly---have to have the primer open. Do we see a connection here? Idle fuel is shut off at the needle. Primer is supplying a bypass route.

 

[GrandPrix74]

Quick update. I removed the carb again. Did more cleaning and adjusted the float to drop about 30mm. I had it traveling far past this distance when I put the new one in. 7 turns out on the low speed idle needle and some adjustments to the idle speed screw and the engine starts with a bump of the starter, idles well, and accelerates well with primer solenoid in auto mode. Not sure why I have to go so far past the recommended 1 1/2 turns out on the needle but that is the only way the sputtering/sneezing stops. Thanks for all the help.