Johnson 6hp choke for full power

[kiwiguy]

Hi Guys, I have an 81 6hp which idles a tad rough but runs like a rabbit at wot. My problem is that I need to pull the choke out slightly to reach full power!!!!. I have checked the tank and lines for leaks, rebuilt the carb and fuel pump. Any ideas? I realise it sounds like the engine is starving for fuel but I'm at the end of my wits.. (and the wife is geting real pissed of with me spending so much time in the garage). So to save a great relationship.. help would be appreciated.

 

[Silvertip]

Re: Johnson 6hp choke for full power

If you need to add choke to reach full power either the carb hi-speed jet was not thoroughly cleaned, or there is still a fuel delivery problem. You might check the fuel pickup in the tank. As you run the engine at WOT, instead of giving it choke, squeeze the primer bulb a few times. If it picks up you probably need to look at the fuel pump again.

 

[kiwiguy]

Re: Johnson 6hp choke for full power

Thank you upinsmoke. I tried the fuel bulb squeeze but didn't help at all. After the carb was re-built and I still had the problem I tore down the carb, emersed all the components in carb clean, used compressed air on everything....<br />Tried another pump off a spare 6hp I have. Some one suggested to me it could be a bad coil...

 

[JB]

Re: Johnson 6hp choke for full power

You just might have some hard deposits in the main jet or in a small passage in the carb, kiwiguy. That would have the same effect as a too-small main jet and make her run lean.<br /><br />I doubt that an exhaust leak would cause your symptoms, though it would make the engine run bad or even die.<br /><br />If you have or can borrow a set of very small machine drills you can clean them out.<br /><br />Good luck.

 

[Xcusme]

Re: Johnson 6hp choke for full power

Have you tried running WOT with the cover off?? If it runs OK with the cover off, you likely have an exhaust/powerhead gasket leak. It doesn''t sound right that a bad coil would be effected by the choke.

 

[kiwiguy]

Re: Johnson 6hp choke for full power

Thank you for all the help. Tore down the carb once again and and cleaned. bolted itback up and it runs fine.

 

[bollard]

Re: Johnson 6hp choke for full power

Kiwiguy,<br /><br />FWIW, for future reference, if you have the carb type that uses a small rubber hose inside, clear out inside the brass nipple where this hose attaches. That was a bugger for me every time I stored the engine, causing the symptom you describe. I would go straight to it and run a thin copper wire in there and it was good to go. Note: since switching to FICHT Ram oil and OMC 2+4 fuel stabilizer, I have not had to do this since. I used to use TCW-3 and Stabil - never again!