Fast Idle Issues - 1988 - Johnson 150

santi10

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Need help! Have a rebuilt powerhead. Disconnected oil side and Rebuilt original VRO. The air motor was broken when I got the motor back after rebuild.Ran last year at a fast idle, 1500 - 1800 rpm's on a good day.I backed the rocker arm for the idle all the way back , it was not even touching the cam follower. Ran fine in gear. Found leak in the old VRO.Plunged leak lost fuel pressure immediately after. Replaced VRO and pulse limiter with new ones. Regained pressure but now it idles at 3200rpm's on the hose. Can this be a timing issue? There is a loss metal bar on top of the Throttle and Shift side arm. Could that be the problem? Is there a mechanism that kicks the rpm's down when the motor gets warm? Ready to give up!
 

Dhadley

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Re: Fast Idle Issues - 1988 - Johnson 150

Are you saying the link that goes from the throttle arm to the timer base is gone?
 

santi10

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Re: Fast Idle Issues - 1988 - Johnson 150

It is there. It is only connected to the throttle arm. It is hanging lose. It has a plastic ball on the end if it.
 
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Dhadley

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Re: Fast Idle Issues - 1988 - Johnson 150

The ball came out of the socket. Without that arm hooked up the timer base will just kinda float around. It may idle high and then never advance to let the rpms advance properly.

A couple of things may have happened - the socket part in the timer base may be worn or missing. Or the timer base could be stuck. When that happens and you advance the throttle it'll pop the ball & link arm out.

If the socket is still there, pop the ball off the arm, pop it into the socket and then snap the rod into the ball.
 

santi10

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Re: Fast Idle Issues - 1988 - Johnson 150

Will try tomorrow afternoon. The timer base moves freely. I wasn't sure what it was at first so I moved it a few times while the engine we running. Was that bad?
 
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Dhadley

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Re: Fast Idle Issues - 1988 - Johnson 150

It probably didn't hurt anything. I'd guess you still have all your fingers too.
 

santi10

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Re: Fast Idle Issues - 1988 - Johnson 150

Yeah that wasn't very smart of me.
 

santi10

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Re: Fast Idle Issues - 1988 - Johnson 150

Would the "fast idle" have anything to do with it? I don't think my temp. gauge is working properly?
 

santi10

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Re: Fast Idle Issues - 1988 - Johnson 150

Worked like a charm!! thanks. The the plastic socket that the balls go into look cracked. They seem to be holding though. Had it idling at 1000rpm's. I was a little concerned though. I put the lower unit in a big bucket full of water to create some back pressure. I connected the earmuffs as well to make sure the water got in. While it was running there was a large amount of oil accumulating in the bucket. It was floating on the water and sticking to the walls. Is that something I should be concerned with?
 
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