Trouble

Englarman

Cadet
Joined
Jul 16, 2005
Messages
10
My wife recently purchased a 1985 ashcraft boat with a 35 hp johnson motor. The problem is that the engine keeps fouling plugs. I was told by the previous owner that the mix ratio was 50/1 and thats what I've been following. The motor fires right up but idles rough when the plug is fouled,Change the plug and she purrs like a kitten . It seems that only the bottom cylinder plug will foul out and it's usually wet with fuel. the top plug has good color and seems to be fine. The motor will run fine afterwards but once the engine cools down it's back to the way it was. I'm not much of a mechanic but I feel that there's something wrong. Should I worry or just keep buying plugs.
 

BoatBuoy

Rear Admiral
Joined
May 29, 2004
Messages
4,856
Re: Trouble

Is the motor also a 1985? What is the model designation? What plugs are you using?
 

Englarman

Cadet
Joined
Jul 16, 2005
Messages
10
Re: Trouble

I believe that the motor is a 1985 motor the model # is J35F1CTS if that helps the plugs are Champion # QL77JC4
 

BoatBuoy

Rear Admiral
Joined
May 29, 2004
Messages
4,856
Re: Trouble

That would be an '83. J35FLCTS<br />INTRODUCES -<br />I-1<br />N-2<br />T-3<br />R-4<br />O-5<br />D-6<br />U-7<br />C-8<br />E-9<br />S-0<br /><br />That is the correct spark plug, should be gapped at .030.<br /><br />Check to see if it getting a good blue-white spark to the spark plug on each cylinder. Spark should jump at least a 7/16" gap.<br /><br />If it were mine, I would remove the carb and clean with carb cleaner. Then re-assemble with new carb kit (about $15).<br /><br />Irregardless of running status, I would also make sure it's pumping water. That's a must-do with an motor of unknown history.
 

Englarman

Cadet
Joined
Jul 16, 2005
Messages
10
Re: Trouble

It's pumping water fine. I had a friend take a look at it and he seems to think that the power pack or the coils may be the problem. I ordered both and if that's not it then at least those three items will be new.
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: Trouble

Don't fall into the trap of throwing parts (and $$$) at your motor. Troubleshoot first - then parts. Having said that you have crud in the carb.
 

Englarman

Cadet
Joined
Jul 16, 2005
Messages
10
Re: Trouble

Thanks for the reply. I was thinking along those lines but didn't really want to mess with the carb. Can the carb be cleaned without taking it off the motor or will I have to remove it.
 

mikeyzx2

Chief Petty Officer
Joined
May 1, 2005
Messages
633
Re: Trouble

Nope, yank it off and disassemble it, crud in the carb will get in little passageways you can easily get to. get a factory service manual for it, that's one thing worth throwing money at.
 

Englarman

Cadet
Joined
Jul 16, 2005
Messages
10
Re: Trouble

Thanks for all the help guy's I think this weekend I will take the carb off and clean it really good.
 

Englarman

Cadet
Joined
Jul 16, 2005
Messages
10
Re: Trouble

Well I found out that it wasn't the carb. I installed the two new coils yesterday and noticed that one of the wires coming from the power pack was broken in two (It was taped together and when I removed the tape I saw it) right next to the boot. well needless to say the bottom cylinder is not fireing. I thought that it was fouling. I put in new plugs and the bottom cylinder plug still looked new except for the fuel. Wha do you guy's sudgest that I do at this point. get rid of this motor and buy a new one or put more money into it.
 
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