1998 Johnson Oceanrunner 200hP Que

mikey456

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Oct 27, 2007
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I have 2 observations to get input on. The first is I pulled all the plugs and noticed 1 plug out of the 6 was completely clean. The other 5 were wet as in normal. I checked this 1 plug to see if it was firing and it was. I did a compression check of the cylinder with this plug and it was 100psi. Checked the others and they were 100psi as well. The location of this plug was the cylinder with the highest carb. I dont have VRO. I mix the gas and oil.

Next, I notice one side of the engine gets hotter than the other. And the cylinder with this very clean plug is also cooler than the rest when idling in the driveway with a garden hose. Does any of this sound strange? What should I inspect?
I appreciate the responses!
 

daselbee

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Re: 1998 Johnson Oceanrunner 200hP Que

I have had a situation exactly like that on an engine I was working on once.

I had good spark on all six, but when I was testing spark, cylinder by cylinder, QS was always active. Turning the key to start activates QS
and it takes about 5-10 secs for QS to drop out, after starting, and it depends on the motor temp and RPM. I was checking spark and done with each cyl before QS kicked out.

Long story short, #2 was dropping spark immediately when QuickStart kicked out. The only way I found it was to use a timing light while running, and sure enough, just the second QS kicked off, #2 quit sparking.

It kept that bank cooler than the other, just like your motor, and #2 plug was always clean.

Cylinder was oiling fine, the only odd thing I noticed was black unburned fuel dripping out the prop, and it was not really that much.

SO, it was NOT the pack, but it was the timer base that was at fault. It was a blue CDI timer base, too, if anyone is wondering.
 

mikey456

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Re: 1998 Johnson Oceanrunner 200hP Que

Oh Wow! And your exactly right. I have unburnt fuel that looks like oil residue running out the exhaust! This is really somethin. Well, this motor got all new everything except the rectifyer. Including the timer base. So now that I think of it, I remember when QS was on, the motor ran fine. When it kicked out, somethimes the motor would drop RPM and spit and shut off. And I did check the cylinder with a timing gun and it was firing. But that was in QS. Im gonna do like you said. I appreciate this very much!
 

daselbee

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Re: 1998 Johnson Oceanrunner 200hP Que

One other thing. I was down one cylinder, so the engine would not develop full power and RPM. How about yours?
Is it performing up to par?
 

mikey456

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Re: 1998 Johnson Oceanrunner 200hP Que

Well, it goes just like this. Motor Cold Starts perfect. Idles until QS drops out. Which sometimes is after a minute or so. Idles from cold fine. After idling about 5 minutes, I would be ready to shove off and go to put it in gear and the motor shuts off as soon as I put it in gear. It will do a spit like a miss and shut off. Start it right up again and it goes to QS and I put it in gear. Under way, it goes on plane and maxes out at 5200rpm. Runs fine on the trip out. Sometimes coming back from say 5 miles out, I cant get but 5000rpm. Sometimes I will get 5200rpm all the way in. Depends on her mood so to speak. But that oil trail out the exhaust baffled me. Then at the end of the season, I pulled the plugs and saw the 1 plug clean. Thought it was odd. I started it twice this week and it ran like it always does. No backfire though. Put the gun to it and it was firing on all. But as you said it was in QS. But my overall opinion of this motor is that something is going on. And that plug being clean may be the culprit.
 

SparkieBoat

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Re: 1998 Johnson Oceanrunner 200hP Que

so if you drop a cylinder after QS, that would be a bad powerpack right?
 

mikey456

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Re: 1998 Johnson Oceanrunner 200hP Que

Thats my thinking. I dont see how the timer base would send a proper signal for QS but quit afterwards. To me Im thinking powerpack. Your thoughts?
 

daselbee

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Re: 1998 Johnson Oceanrunner 200hP Que

so if you drop a cylinder after QS, that would be a bad powerpack right?

In my case, I swapped packs, did not fix. I then swapped timer bases, and it fixed the problem.

I have a bunch of parts, and a test powerhead on a stand. I was able to take the bad timer base to the test head, and re-create the problem.
 

mikey456

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Oct 27, 2007
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Re: 1998 Johnson Oceanrunner 200hP Que

Amazing stuff. Appreciate this.
 
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