Johnson 200hp slow to take off.

[machinist]

It is a 1990 JOhnson 200hp. Crank it up put it in gear its weak trim it all the way down and give it full throttle it creeps along for about a minute then bam it gets up and runsss. You can stop with the motor still running take off agian and it gets up and moves, is it cold natured? Stop fish for 30 minutes and then it goes weak on take off agian. Thought maybe it was a fuel issue but doubt it run at all if it was. what do you think?

 

[metriccrescentwrench]

Re: Johnson 200hp slow to take off.

I've got a '90 Johnson 200 also, and have had to learn way more about that engine than I ever wanted to. If you don't yet have the factory service manual you really need to get one, they're worth their weight in gold.

Your problem sounds like possibly a timing issue, or possibly something to do with quickstart. What quickstart does is give 5 degrees of timing advance below a certain rpm for 5 seconds every time the engine is started, and also until it warms up. For starters, see what the idle timing is when you start the engine cold, then watch it 'till it warms up and see what it does when quickstart finally turns off.

 

[machinist]

Re: Johnson 200hp slow to take off.

I have figured out my problem with the lag out of the hole. I was getting an alarm at the time due to me wireing the oil pump back up. The auto pump had been disabled by the previoius owner and i mix the oil direct. Once i unwired it and got it back on the water the alarm was gone and it ran on command. So when it thinks its not getting oil the motor goes into some kinda lag mode on take off as a warning is the best i can figure.

 

[daselbee]

Re: Johnson 200hp slow to take off.

Not a valid conclusion. There is no system to keep the engine from turning up if ANY alarms go off. It is not that smart.
You problem will likely come back.

 

[metriccrescentwrench]

Re: Johnson 200hp slow to take off.

There is no system to keep the engine from turning up if ANY alarms go off.

That engine has SLOW mode that kicks in on overheat. As soon as it gets an overtemp signal it limits rpms to under 2500 (as I recall - I'm working from memory on the exact number) until both the overtemp condition clears and the engine is restarted. I honestly can't remember if there's any rev limiting action associated with the oil pump or not, my engine had the oiling system disabled and I've never had to mess with it. There's another possibility, although a slight possibility, that since both alarm conditions go to the same horn, the oil alarm was feeding back through a bad diode and making the power pack think it had an overheat condition. But it is strange that the condition magically cleared itself.

 

[daselbee]

Re: Johnson 200hp slow to take off.

Oh...what was I thinking...my bad. You are absolutely right.
But, I was thinking on his symptoms...and I stand by my statement...there is no system that will keep his engine from revving up LIKE HE DESCRIBES.....he says it runs fine after it picks up speed. SLOW will not act like that.

If the engine overheats, it will go into slow mode, and limit the revs to 2500 just as you say, but it is not what the is describing.

There are no engine limiting systems related to oil, fuel vacuum...etc. only the temp. I hope this kinda clears up my poorly worded post, and I still think his problem will come back.

 

[machinist]

Re: Johnson 200hp slow to take off.

This seem to be kinda a mystery and cant 100% say i know what the problemwith the lag was but, its running strong now. Last weekend i took it out and was getting the same lag and beeping as i first posted. I stoped unpluged the wiring, disconnected and then connected the battery cables cranked it back up and had no lag and no beeping. I ran it hard for a while, roughly 18 gallons of gas through it with no problems so who knows?. The prob may come back but as for now all seems well.

 

[metriccrescentwrench]

Re: Johnson 200hp slow to take off.

Last weekend i took it out and was getting the same lag and beeping as i first posted.

Well, actually in your first post you didn't mention the alarm.

I've got to agree with daselbee, that's a very strange sounding situation. I can only think of one really really far fetched, very unlikely scenario where the oil alarm could cause that ignition to go into SLOW, but if that happened it would stay in SLOW and not start running normally as you describe.

Now one thing that hasn't been mentioned is that there's also a vacuum switch T'd into the fuel line just ahead of the fuel pump. If activated it too sounds the alarm, it's purpose is to alert you to a fuel delivery problem such as plugged filter, bad check valve, pinched line, etc. that may hamper fuel flow and potentially harm the engine. Is there any possibility this has something to do with whay you've experienced?

 

[daselbee]

Re: Johnson 200hp slow to take off.

Yes, this is the first about an alarm....

But, if it were mine, I would look at the link and sync very carefully. It is a free inspection, and to describe it quick and dirty, from idle, as you advance the throttle, the timer base should rotate smoothly under the flywheel as you apply throttle to WOT. I am not suggesting you do this with the engine running. Do it with the engine off, and note the smooth movement of the timer base in relation to the throttle. The timer base should begin to move just a bit before the carbs start to open, so you have an advanced timing as the gas starts flowing, and the engine accelerates.

That is quick and dirty. The actual link and sync settings and adjustments are in the factory service manual, and it is an involved procedure. But you surely can look and inspect for free. Who knows, you may find a binding timer base that is stuck in dried grease that actually slowly finds the WOT position well after the linkage has travelled to WOT. Am I making sense? That might explain the lag, as well as many other factors.

 

[machinist]

Re: Johnson 200hp slow to take off.

As far as the fuel system, it could of been a problem but i never touched it in this whole deal. And now it seems to be doing good. With lack of a lot of experience its been the trial and error theory. So i would have to say that in my mind i dont think that it has anything to do with the vacuum switch. Daselbee it does make sense and that has checked out to be fine. I will have to set back and see if the problem comes back.