1988 Johnson 50 vro spits & idles rough.

[skelly]

1988 Johnson 50 HP VRO spits & idels rough, I've cleaned and rebuilted carbs but no luck. Took it to the shop, they said that one carb was sucking air and cleaned & rebuilt carbs again. The thing runs better,but i still have the problem!!I checked vro and fuel lines for leaks but don't apear to have any. primer ball stays firm, Help!! Open for suggestions.<br /> Thanks. Skelly. <br /><br />------------------

 

[nickster]

Re: 1988 Johnson 50 vro spits & idles rough.

Just out of curiossity when you or the other person had the carbs off did you check to see if the reed plates behind the carbs was good. try checking compression and see if one cylinder is down. Like I said might have bad reeds<br /><br />------------------

 

[skelly]

Re: 1988 Johnson 50 vro spits & idles rough.

Thanks for your Input Nickster. <br /> Got good compression .I will pull the carbs again & check the reeds as you sueggested, It might take awhile to get to it. thanks again. <br /> Skelly. <br /><br />------------------

 

[12Footer]

Re: 1988 Johnson 50 vro spits & idles rough.

Run some carbon cleaner thru it. Then change the plugs. I doubt it is a fuel delivery problem.<br />The timing may be out. A reed may be staying open too long. It may be a bad plug wire (best detected visually on a dark night--look for arcing)...But do the cheap stuff first.

 

[clanton]

Re: 1988 Johnson 50 vro spits & idles rough.

Thermostat working, engine up to temp? The last carb I did on a 50, after 2 hours in carb cleaner, the pickup tubes were still stop up. I pushed small copper wire thru tube to get junk out.

 

[skelly]

Re: 1988 Johnson 50 vro spits & idles rough.

Thanks for your Input Guys.<br />I have looked at motor at night to check for arking,did not find any. I use Johnson tune up cleaner In the Spring & Fall, But I have Not Checked the thermostat. where on that motor is the thermostat located? It May be stuck open.I never thought of that one.<br /> Thanks! Skelly.<br /><br />------------------

 

[skelly]

Re: 1988 Johnson 50 vro spits & idles rough.

need more input please!<br /><br />------------------

 

[12Footer]

Re: 1988 Johnson 50 vro spits & idles rough.

How about the carb gaskets? If you tried to re-use them, you can sometimes get-away with them. But 1 outta 4 times, it's just squished too much to get a good seal.<br />Also, check the fuel pump filter.<br />When idling ruff, try a shot of WD40 in the carb to see if it picks-up slightly.<br />At least, this may help you determine which carb is giving you grief.

 

[hondon]

Re: 1988 Johnson 50 vro spits & idles rough.

First check to see that both throttle butterflies are closed completly at idle.These twin are really touchy when it comes to sync and link and if one or both are hanging open even a **** at idle will run like crap.

 

[skelly]

Re: 1988 Johnson 50 vro spits & idles rough.

Thanks for the input Hondon<br /> I'll Check those butterflies as soon as i get a chance! I work for Potomac Electric Power Co. in Wash. DC. and the Manhole covers are Flying here! <br /> Thanx again. <br /> Skelly.