Idle problem with 200 Johnson..

[Bassin' fool]

I have an 87 model Johnson gt200 on the back of my ranger that won't hardly idle while in gear. It runs great at full throttle, and will even idle good after it's been running awhile but I have to choke it every time I start up (even if it's only been shut off for 10-20 mins) and hold it about half throttle till all the smoke clears before it will idle while in gear, also it sounds a little slobbery when I take off until it gets on plane and a little higher rpm then it smooths out and runs fine. Was wondering if anybody has ever had this problem or knew what's causing this? I've only had the boat a little over a month so I'm not ruling out operator error either.. 

[fishinwrench]

Several things need to be checked.  First verify that the engine has acceptable compression.  Then verify that the timer base (under the flywheel) is moving freely throughout the throttle movement range.  

Check the throttle cam roller on the carb linkage to see if the outer sleeve of the roller has deteriorated and fell off.

Once those three things are either fixed or determined to be "ok", start it up on a hose and do a "cylinder drop test".  This is done by allowing the motor to warm up at idle speed, then with insulated pliers remove the spark plug leads and reattach them one a time and compare the running attitude of the engine as each lead is removed.   If removing any one plug wire causes a different reaction.....or no reaction at all then that cylinder  has an issue that needs to be addressed. Could be a fuel or an ignition problem.   

After you've done the above report back and we'll go from there.  

[Old plug]

That sounds just like  my 115 when the duel lines were fouled.

 

[Bassin' fool]

What it sounds to me like is that it's just losing some fuel pressure somewhere, I know the primer bulb never seems to get very hard and I have to pump it almost every time I start it, I've worked on a few outboards just never anything this big. What confuses me is that it runs like a top once it gets goin but I'll check those things out too and see where it all takes me 

[fishinwrench]

It doesn't take much fuel pressure to keep 3 carb bowls full.  If the primer bulb never gets hard then either the bulb is bad or there is a leak somewhere (hose, pump diaphragm, or needle valve). 

When priming an outboard always point the arrow on the bulb skyward to push any trapped air out of it. 

I actually have the fix for the typical hard starting cross-flow Johnson/Evinrudes, but it took me years to figure it out, and since not even the factory manuals describe a cure I've elected to keep it a secret and make money off of it.

[Bassin' fool]

I took the boat out last night for a short boat ride just to refresh my memory on what was going wrong and here's what I found. I had the same idle problem as listed above, but now it seems to fall in its face when I take off, it took quite awhile for it to get on plane and build rpms and once it did it never got above 4,200 rpm. The boat usually runs around 58-62 mph depending on temp and water condition but never got above 48 on calm water last night. It still ran very smooth but acted like it had no power, I'm not sure if that changes anything that I need to look for or not but I'm going to do a compression test today and go from there. The other thing I noticed was when I pumped the primer bulb till it was firm it started dripping fuel out of the front of the engine. No lines seemed to be leaking anywhere so is this normal or do I have a problem with a carburetor? 

[fishinwrench]

Inlet valves are leaking.  You need a carb job....but not before you verify compression and check the linkage movement, throttle cam position and overall sync.  

The leaking inlet(s) are not what's causing the loss of max RPM's.

[Old plug]

Tell me wrench could he not have a problem caused by running to much E87 fuel thru it.

[Bassin' fool]

Ok so now I'm about to make myself sound pretty stupid, took the engine cover off in the driveway this morning and pulled the breather cover off the front of the motor to see if I could find which carb was leaking. Pumped the primer bulb twice and shot a stream of fuel out of the fuel inlet line about an inch from the pump, also had one plug wire that got pulled off when I put the hood on last time so I had no fire on one cylinder. The compression checked out good and even on all 6 

[fishinwrench]

7 hours ago, Old plug said:

Tell me wrench could he not have a problem caused by running to much E87 fuel thru it.

Excessive ethanol in the fuel will cause problems with OLDER rubber components, but the new expensive rubberized compounds are fairly impervious to it as far as I've experienced so far.    

Things made of rubber have never lasted FOREVER so I don't see what all the hullabaloo is about.  Personally I don't have any problems getting outboards to run good on any fuel that gets brought in here....as long as it is reasonably fresh.   Ethanol enhanced fuels do NOT have much of a "shelf life" so if you buy some you need to burn it up ASAP.  Don't fill your tank and expect it to last 3-4 months, because it will go bad way before then.  A couple weeks tops.

Treat it like milk and I don't think you or your outboard will have any problems with it.