2000 Johnson 150 VRO Carb Cleaning

[Theoutdoorsman]

Curious if anyone's tried this .... https://youtu.be/rtvKZyxbVdg

I'm not a fan of "magical fixes", but this does appear plausible. I'm anxious to know if anyone here has actually tried to do this, and would care to share their results. My outboard is idling rough, often dies at the ramp while trying to load/unload the boat. It does, however, run like a champ on top end. For that reason I suspect my carbs are dirty, but not so dirty that an attempt like this wouldn't "cure" the issue. Any thoughts?

 

[jakedaawg]

post a model #...Maybe explain the problem a little more in detail...some of us do not have the bandwidth to watch a video...at least I don't...

I will assume for this post that you have a 60 degree looper. As you look at the front of the carbs and throttle bodies there are some little brass openings...These need to be clear for idle.

In most cases an Idle issue can be traced to either the OIS or the throttle bodies or the top of the VST leaking.

Once again, model # is most important to recieve any valuable information.

 

[Theoutdoorsman]

Model # is:
J150PLSSC

Just has trouble idling. Dies often, and struggles on restarts. On top end, no issues whatsoever, runs GREAT.

 

[jakedaawg]

When it dies is it a lean sneeze that kills it or does it just fall off gradually? What plugs are you running? What are your compression numbers? Have you preformed an open air gap spark check, and could it jump a 7/16" gap?

Squeeze bulb till firm, continue gently squeezing, does the bulb continue to depress? If so check the top of the VST for leaks, very common.

Any chance you have can run at idle under load either at the dock or in a livestock trough? If so using plastic pliers, pull each plug wire one at a time and note any change. If you pull one and no change you then have a direction.

As mentioned earlier I usually find these idle issues to end up being a carb service or throttle body service/cleaning.

Sometimes you will also find the bowls to be leaking.

With the air silecer off you can look at the front of the carbs. There are some little openings, a straw from a carb cleaner can can just fit in them, give each a very quick squirt. You do not want to run much through as there is no oil in carb cleaner. Just as quick as you can press the button then wait a bit and do the next one. While not a proper cleaning sometimes its all it takes. The real way to do it is to service the carbs and throttle bodies but that is a job on these.

 

[Theoutdoorsman]

When it dies is it a lean sneeze that kills it or does it just fall off gradually? What plugs are you running? What are your compression numbers? Have you preformed an open air gap spark check, and could it jump a 7/16" gap?

Squeeze bulb till firm, continue gently squeezing, does the bulb continue to depress? If so check the top of the VST for leaks, very common.

Any chance you have can run at idle under load either at the dock or in a livestock trough? If so using plastic pliers, pull each plug wire one at a time and note any change. If you pull one and no change you then have a direction.

As mentioned earlier I usually find these idle issues to end up being a carb service or throttle body service/cleaning.

Sometimes you will also find the bowls to be leaking.

With the air silecer off you can look at the front of the carbs. There are some little openings, a straw from a carb cleaner can can just fit in them, give each a very quick squirt. You do not want to run much through as there is no oil in carb cleaner. Just as quick as you can press the button then wait a bit and do the next one. While not a proper cleaning sometimes its all it takes. The real way to do it is to service the carbs and throttle bodies but that is a job on these.

When it dies, it usually falls off gradually. Not sure on the plugs. Compression is approximately 90 lb each cylinder (fairly even). Haven't performed an air gap spark check, as the plugs are new. The squeeze bulb was hard until this last trip out. Now it doesn't get hard. The problem was the same when it "would" get hard. That problem just occurred this last trip out. Sorry, I'm not familiar with the lingo. What does VST stand for? I'll have to pull the plug wires at the dock this weekend for ya. I'll check the "little openings" on the front of the carbs here at home beforehand. While I'm at it, I'll also replace the bulb. I just bought the boat, and can't really say for certain when the last time it was changed. Also, I haven't noticed any raw fuel inside with the cowling removed.

 

[Theoutdoorsman]

Squeeze bulb till firm, continue gently squeezing, does the bulb continue to depress? If so check the top of the VST for leaks, very common.

Bulb stays firm.

Sometimes you will also find the bowls to be leaking.

I have found no indication of a leaking carb bowl.

With the air silecer off you can look at the front of the carbs. There are some little openings, a straw from a carb cleaner can can just fit in them, give each a very quick squirt. You do not want to run much through as there is no oil in carb cleaner. Just as quick as you can press the button then wait a bit and do the next one. While not a proper cleaning sometimes its all it takes.

This was actually a step mentioned in the video.



I can confirm the above mentioned video did help my idling issues. It's not perfect, but FAR better now. Getting the boat back on the trailer was much much easier. Only stalled on me once. I have also noticed that the outboard is a bit more responsive to even the slightest change in throttle position now, so I know the process has helped. What I also notice, which hasn't change at all, is that my rpm's will drop down about 200-300 rpm's occasionally and then recover. I'm thinking I still have some minor blockage? I'll do the spark test next to confirm she's getting good fire. I'm almost certain it is though. What are the recommended plugs for this outboard? Any idea?

 

[jakedaawg]

Champion QL78YC but I feel the 150 HP do better with the optional QL77JC4, they certainly idle better. I do not run NGK but that is more of a personal preference...absolutely do not mean to start a spark plug thread here!!!

 

[Silvertip]

Once again, primer bulbs do NOT and are not supposed to stay firm when the engine is running. Fuel is drawn through the bulb -- not forced through it, hence there is zero pressure in the fuel line. In fact there is a slight vacuum which is why a bulb gets sucked flat if there is a restriction in the fuel system between the tank and bulb.

 

[Theoutdoorsman]

Champion QL78YC but I feel the 150 HP do better with the optional QL77JC4, they certainly idle better. I do not run NGK but that is more of a personal preference...absolutely do not mean to start a spark plug thread here!!!

I'll pull one, and we'll see what's in there now. I'll definitely be picking up a new set of the recommended plugs. Thanks. While we're on the subject, what are your thoughts on permagap plugs? I have a set in my evinrude 140, and I've had good luck with them.

EDIT:

After pulling the plugs, I found the NGK's installed (NGK - BPR7HS). Can you tell me the obvious differences in the Champion QL78YC, and the recommended Champion QL77JC4? This forum post seems to contradict your recommendation, but it appears the YC plug fires deeper in the cylinder. Curious why you run the JC4 instead?

http://forums.iboats.com/forum/engi...oard-brands/149610-champion-ql77jc4-vs-ql78yc

 

[Theoutdoorsman]

Once again, primer bulbs do NOT and are not supposed to stay firm when the engine is running. Fuel is drawn through the bulb -- not forced through it, hence there is zero pressure in the fuel line. In fact there is a slight vacuum which is why a bulb gets sucked flat if there is a restriction in the fuel system between the tank and bulb.

We're all in agreement on this, I'm pretty certain. When initially primed, prior to starting/re-starting, they "should" get hard however.

 

[Theoutdoorsman]

Spark is good. This outboard just doesn't want to idle. No lean sneezes. It just ceases to idle, as if it is starving for fuel. Falls off like it runs out of fuel. I have a service manual on the way now! It's gotta be something simple. Runs like a beast at WOT!

 

[Theoutdoorsman]

I'm replacing the spark plugs with the recommended Champion QL77JC4 plugs today.



EDIT: Upon pulling the NGK plugs, I noticed the bottom two carbs on the starboard side weren't as wet as the other 4. I suspect my issue lies in those two carb assemblies. All NGK plugs have now been replaced with the recommended Champion QL77JC4 plugs. If no noticeable change is observed, I think I'll pull the previously mentioned carbs, and give them a good scrub. Suggestions?

 

[JGShooter]

I have done this at the dock to clear small bits of trash... While the Engine is running, hold your hand over the carb intake for just a second it will choke the carb and fuel will start to pour from it. This increase in vacuum sometimes will clear small bits of trash.. again only for a second.

 

[jakedaawg]

I'm replacing the spark plugs with the recommended Champion QL77JC4 plugs today.



EDIT: Upon pulling the NGK plugs, I noticed the bottom two carbs on the starboard side weren't as wet as the other 4. I suspect my issue lies in those two carb assemblies. All NGK plugs have now been replaced with the recommended Champion QL77JC4 plugs. If no noticeable change is observed, I think I'll pull the previously mentioned carbs, and give them a good scrub. Suggestions?

I think you will find that you also need to do the passages in the throttle bodies. Requires replacment welch plugs. Manual will tell you.

 

[Theoutdoorsman]

Manual in hand now! My only concern is the recommended tool for timing the outboard. Is it possible without it?

 

[cfauvel]

Manual in hand now! My only concern is the recommended tool for timing the outboard. Is it possible without it?

I wouldn't mess with timing....at least not just yet....the motor runs fine off idle.

mark each carb to its location, remove the carbs and clean the idle circuit passage ways, as other have mentioned, then look up Link/Sync procedure for your motor.

I am pretty sure that for this motor the butterflies have to be fully closed to properly set the idle and for the idle circuit to properly suck the metered fuel/air....

JakeDawg, Joe Reeves and several others will know how to properly set the idle on this motor.

 

[Theoutdoorsman]

If I pull carbs, the link and sync procedure will need to be performed. I would feel more comfortable knowing it's possible without the recommended $250 tool that the manual calls for. I'm not at all concerned with cleaning the carbs. That, I can handle.

 

[Theoutdoorsman]

Joe Reeves has helped me in the past. It'd be nice if he stumbled upon this thread.

 

[cfauvel]

If I pull carbs, the link and sync procedure will need to be performed. I would feel more comfortable knowing it's possible without the recommended $250 tool that the manual calls for. I'm not at all concerned with cleaning the carbs. That, I can handle.

ugh....for this motor, the carbs are on each side right? not close together?

I'll have to defer to others if there is some magic that the tool does...my motor the carbs are real close together right in the middle....lync & sync is pretty easy on mine. Hopefully someone chimes in....learning is always good.


I see you have an idle mixture screw for each carb...what does the manual say that the initial setting should be....it maybe just a matter of adjusting those screws.

 

[Theoutdoorsman]

The manual lays out the initial presets for the idle adjustment. I just hate to start turning anything without knowledgeable advice. Ya know?