Re-built Carbs....STILL sneezing...please help!

searay24

Cadet
Joined
Apr 2, 2007
Messages
16
Alright.....I have a 1973 Johnson 115. I Was having a problem with it sneezing REALLY bad!! I replaced the spark plugs, re-built the carbs, and re-built the fuel pump. After doing all of this it seemed to help out quite a bit with the "sneezing" It used to do it just idling and low speeds and it used to do it constantly. Now it only does it in low speeds....idle seems to be ok. when i have it at mid and full throttle it runs exellent.....just the low speeds when i'm in the no wake zones which are everywhere around here. It sneezed so bad twice it totally stalled. It also seems to run a bit rough but again only at very low speeds....when I give it more throttle the problem seems to go away but then i'm causing wake which is no good. I am going to try and attempt a link & sync....i don't know what else to do. Seems pretty complex to do a link and sync and being that this is my first boat i'm new to all of this. I do have the factory service manual. Any suggestions at all? I really apprecitae you guys helping me out....Just want to get it running right again in time for summer! Also i didn't take apart any of the linkage on the carbs. I kept all of those intact.
Thanks
James
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Re: Re-built Carbs....STILL sneezing...please help!

The sync stuff is very important. It definatly will make it sneeze and run poorly if the carbs aren't opening at the right time in the right amount.
 

searay24

Cadet
Joined
Apr 2, 2007
Messages
16
Re: Re-built Carbs....STILL sneezing...please help!

Why would it do this only at slow speeds?

Thanks for the reply
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: Re-built Carbs....STILL sneezing...please help!

I would recommend that you focus on the ignition wiring: Disconnect and clean every connection, especially the ground wires; Carefully examine the ignition coils for discoloration, cracking or melting and replace where indicated; Remove the ignition coils and clean the contacts and grounding points; If you are using conventional plugs, set the gap at .03 rather than .04; Replace the spark plugs if you have any doubts.

If for any reason you are not sure that the spark plug wires are OEM wires, you may want to replace them with OEM wires.
 

searay24

Cadet
Joined
Apr 2, 2007
Messages
16
Re: Re-built Carbs....STILL sneezing...please help!

I did notice slight cracks in the coil housings. But then again...why only at low speeds does it want to act up? I bought Champion plugs and the gap is set at .30
 
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