1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

[jwellcraft]

My buddy has this motor and just replaced the pp, trigger (timer base) and 6 coils since they were never replaced and has a spit on the #5 cylinder which it had a miss before all these parts were replaced. The carbs were not rebuilt ever but were taken apart and cleaned. It starts fine and once the cold start cuts out and the rmps lower it starts spitting on the #5 cylinder. Once I pull the coil wire off on that one it stops spitting so it is definately that one. Tried turning the idle mixture screw out to richin it up but nothing happens and when I pull the #5 spark plug it comes out dry and if I remove the recirclation hose for that cylinder it spits from the nipple but no fuel just a dry spit. Any ideas what else could be the prob? I own a 1994 150 Ocean runner and I know about the check valves on those and stuff but are these on the 1998 225 much different?

 

[daselbee]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Spitting how? Gas out the front of the carb? If so, double check the sync of the carb throttle plates. Make absolutely SURE that they are all closed perfectly when at idle position. #5 and #6 are especially suspect, because they are basically separate from the uppers, and have an adjustable link to connect the throttle shafts. Very easily overlooked and very easy to misadjust.

I find it easier to do the throttle plate sync with the black carb bodies off. All adjustments, and the ability to see very clearly, makes it easy.

I had the same issue with mine once, saw #6 was slightly open at idle, adjusted it, spitting stopped, and the idle improved greatly.

 

[jwellcraft]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Thanks, its actually sneezing but I don't see fuel coming out from the front of the carb (stays dry unless you choke the motor or put your hand over it). Was it a bad idea to adjust the idle mixture screw? I looked at the throttle plates and they looked all tightly closed but I will double check. How many turns out from seated should I come out on the idle mixture screw?

 

[SparkieBoat]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

3 turns to start and they must all be adjusted the exact same and you must test on the water running the boat in between each adjustment...also make sure you soft set those screws as you can cause the to shank if you over tighten and then need to replace the screws.

 

[daselbee]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Ok...now we see....lean sneezing. Clean carbs thoroughly, pay special attention to the brass tube that extends down into the float bowl, remove the side plate (5 screws) clean that passageway, remove the small aluminum plate on the throttle body (4 screws) and make absolutely sure that the microholes that go through into the throttle bore are clean. You can barely see them. Small strand of wire will get in there. Blow thru all passages with air in both directions.

I disagree with the three turns out to start. On my engines I am having to go as much as 7 to 8 turns out to get the idle right. But, it is not really as critical as you might think. You get it right to within a turn, you probably will not be able to tell any difference.

Don't be intimidated by it....just count your turns, and you can always go back to where you were. In fact, I would recommend that you experiment a bit. Turn one screw all the way in on wpone carb and note what it does to the idle. It won't hurt a thing. I experimented a bit and found that for the idle bleed jet, one size up is roughly equivalent to one turn OUT on the idle needle.

Example: You have a perfectly idling '96 200. It has #27 jets in the idle bleeds, and your screws are at 6.5 turns out. (Just for example.)

If you replace the #27s and put #30 jets in, you can then turn the idle screws IN three turns to get the same mixture, and same perfect idle performance that you started with. So you would have #30s and 3.5 turns out for the same mixture.

You may or may not be interested in that...just thought I would throw it in.

When you get it fixed (no lean sneeze), be sure to ask me to tell you in detail the trick to fine tuning each carb easily.

 

[daselbee]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

I looked at the throttle plates and they looked all tightly closed but I will double check.

I have a hard time looking at the plates to tell if they are cracked open a bit. I have to tap them with my fingertip. You will hear a different sound from the plate if it is open. By open...i mean a VERY small opening...down in the .010 range. That's enough to screw up your idle and cause gas mist to spit back out the front of the carb. (Sorta looks like a leaking reed, but not as much gas mist coming out.)

 

[jwellcraft]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Thanks Sparkie, I only adjusted the #5 / #6 and I wont trouble the others.

 

[jwellcraft]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Thanks Sparkie, I only adjusted the #5 / #6 and I wont trouble the others.

I also was going to say 3 turns sounds a bit lean because on my 150 I start at 7 turns.

 

[Faztbullet]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

I have only seen this a couple of times and if you 110% sure that carbs,gaskets,reeds,reed gasket & bolts,throttle plates are correct its a broken seal ring on crank. What happens is a crankcase misfires between cylinders.Also the carb setting on the adjustable idles is usually about 5-1/2 turn out.

 

[jwellcraft]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Ok...now we see....lean sneezing. Clean carbs thoroughly, pay special attention to the brass tube that extends down into the float bowl, remove the side plate (5 screws) clean that passageway, remove the small aluminum plate on the throttle body (4 screws) and make absolutely sure that the microholes that go through into the throttle bore are clean. You can barely see them. Small strand of wire will get in there. Blow thru all passages with air in both directions.

I disagree with the three turns out to start. On my engines I am having to go as much as 7 to 8 turns out to get the idle right. But, it is not really as critical as you might think. You get it right to within a turn, you probably will not be able to tell any difference.

Don't be intimidated by it....just count your turns, and you can always go back to where you were. In fact, I would recommend that you experiment a bit. Turn one screw all the way in on wpone carb and note what it does to the idle. It won't hurt a thing. I experimented a bit and found that for the idle bleed jet, one size up is roughly equivalent to one turn OUT on the idle needle.

Example: You have a perfectly idling '96 200. It has #27 jets in the idle bleeds, and your screws are at 6.5 turns out. (Just for example.)

If you replace the #27s and put #30 jets in, you can then turn the idle screws IN three turns to get the same mixture, and same perfect idle performance that you started with. So you would have #30s and 3.5 turns out for the same mixture.

You may or may not be interested in that...just thought I would throw it in.

When you get it fixed (no lean sneeze), be sure to ask me to tell you in detail the trick to fine tuning each carb easily.

Thanks daselbee, helpful info.

 

[jwellcraft]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Hi guys, I just got through taking this #5 carb back off and clenaing it again (all passages), the 5 screw side plates, the 4 screw side plates on the manifold and cleaned the 5 of those little needle holes and everything went through clean and smooth. Fired it up and ran smooth for about 20 seconds and starting sneezing again on that same one, I unplugged the coil wire and the sneezing stopped but it idled really low. So I decided when that one was unplugged to unplug others to see if there was any difference (one at a time) and as I unplugged #2 the motor idled up and sounded smooth but was idling high (1,500 or so). Any other things need to be checked and cleaned for that #5 and would anyone suspect anything with the #2?

 

[daselbee]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

#5 is firing exactly opposite of #2 on the 360* complete circle cycle of the engine's revolution. So, unplugging #2 with #5 unplugged balanced out the engine. Seemingly made it run better.

If a cyl is lean sneezing, you must look for reasons for the leanness. Tricks are: put two fingers down the throat of each carb at idle. Do it the same way on all six. The one that is sneezing will richen up and smooth out. Also, put a toothpick in the idle air bleed to temporarily stop the air flow there. That will richen it up a bit to help you zero in on the cyl. Cover each carb with your hand or a rag for a second...just til it bogs...and see which cyl acts differently from all the rest. When doing these things, make sure you do it the same on all carbs...don't add a variable by using your hand on some and a rag on others.

Make sure those idle screws are out at least 7 turns too. Once you get it fixed, then start fine tuning the idle mix screws.

Extra air from a leaking gasket, the spaghetti gasket on the back of the carb, a fault in the recirc valves, cracked recirc hose, stuff like that.

 

[Faztbullet]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Not to insult ya but make sure your working on the correct carb as looking at front of engine, carbs on right side feed starboard ands carb on left feed port.

 

[daselbee]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

^^^^^Wow, very good point Fazt. Not immediately apparent to everyone.
Another way to tell is the highest carb feeds #1, and it is on opposite side of engine from #1.

 

[jwellcraft]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Damn, well this will explain it all so I guess I was working on the #6 carb then. So you are saying if I am on the carb side of the engine and the #5 cylinder is the prob I need work on the carb to the right then. We'll adjust the mixture screw on the other carb to see if that helps the prob before taking the carb apart. Thanks will keep you guys posted on any progress.

 

[daselbee]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Damn, well this will explain it all so I guess I was working on the #6 carb then. So you are saying if I am on the carb side of the engine and the #5 cylinder is the prob I need work on the carb to the right then. We'll adjust the mixture screw on the other carb to see if that helps the prob before taking the carb apart. Thanks will keep you guys posted on any progress.

Don't forget to check that #5 throttle plate again, to make sure it is closed. Sounds like you checked #6. You would be very surprised at how just .010 gap will affect the idle.

 

[jwellcraft]

Re: 1998 Johnson 225 oceanrunner missing/spitting on #5 cylinder

Thanks, I checked both throtlle plates on the bottom carbs since they are seperate shafts and they were fine. Pulled off the correct carb and just went right through it and set the idle mixture screw at 7 turns out from seated and sneezing gone. Adjusted the #5 / #6 idle screws until the sneeze returned then came back out a 1/4 to 1/2 turn and idling pretty good except for a slight surge but not sure how these 225's suppose to idle anyway.